Food Chemistry and Biotechnology

Transcription

1 Report on the 2 nd FCUB ERA Workshop Content: Narative repot List of participants Lecturers CVs Program Abstract book Poster of the FCUB ERA Photo gallery Narative report The 2 nd FCUB ERA workshop took place on 18 th - 19 th October 2011, Belgrade, Serbia. The theme of the workshop was: Food Chemistry and Biotechnology The venue of the workshop was at the Faculty of Chemistry, University of Belgrade, Studentski trg 16, Belgrade, Serbia. The deadline for abstract submission and travel grant application (open for young researchers and PhD students) was 15th of September. In total, 42 contribution have been received by the scientific committee and 27 travel grants have been granted to participants from 8 different countries.

2 The meeting topics (sessions) were: Session 1: Plant food chemistry and biochemistry Session 2: Animal food chemistry and biochemistry Session 3: Food analysis Session 4: Food biotechnology Session 5: Dairy industry Prof. Živoslav Tešić, President of 2 nd FCUB ERA Workshop, opened the workshop. The guest were welcomed by the Vice Dean for Science of the FCUB, Prof. Marija Gavrović-Jankulović, who also presented the history and R&D activities of FCUB. In total, 70 participants attended the workshop representing 19 different institutions (14 institutions from abroad and 5 from Serbia). The highest number of foreign participants came from Romania, Greece, Tunisia, Poland and Belgium. Institutions from abroad: 1. High School of Food Industries of Tunis, Tunis, Tunisia 2. National Institute of Research and Development for Food Bioresources IBA Bucharest, Bucharest, Romania 3. Department of Pharmaceutical Botany, Medical University of Lublin, Lublin, Poland 4. School of Chemical Engineering, National Technical University of Athens, Athens, Greece 5. Institute of Food Chemistry, University of Hohenheim, Stuttgart, Germany 6. Research Institute of Biomolecule Metrology Co. Ltd Enokido, Tsukuba city, Ibaraki, Japan 7. Institute for Biological Research and Biotechnology, National Hellenic Research Foundation, Athens, Greece 8. Research Group for Technology and Quality of Animal Products, Catholic University College Ghent, Ghent, Belgium 9. Institute of Chemistry, University of Silesia, Katowice, Poland 10. VTT Technical Research Centre of Finland, Espoo, Finland 11. Department of Analytical Chemistry and Pharmaceutical Technology, Vrije Universiteit Brussel (VUB), Brussels, Belgium 12. National Research Centre Kurchatov Institute, Moscow, Russia 13. Institute of Soil Science and Cultivation State Research Institute, Puławy, Poland 14. INRA, UR1268 Biopolymères Interactions Assemblages, Nantes, France Institutions from Serbia: 1. Faculty of Technology, University of Novi Sad, Novi Sad 2. Faculty of Technology and Metallurgy, University of Belgrade, Belgrade

3 3. Institute of Food Technology and Biochemistry, Faculty of Agriculture, University of Belgrade, Belgrade-Zemun 4. Faculty of Biology, University of Belgrade, Belgrade, Serbia 5. Institute "Kirilo Savić", Belgrade, Serbia The poster session included 31 poster, presented in front of the Lecture Hall. The Scientific Committee attended the poster sessions and decided on the best poster presentations. During the closing session, the best posters were awarded with a Diploma and a small prize: 60 for 1st place, 40 for the 2nd and 20 for the 3rd place. Best poster prize winners were: 1 st Prize: Elena S.Chernetsova, National Research Centre Kurchatov Institute and People s Friendship University of Russia, Moscow 2 nd Prize: Maja Krstić, Faculty of Chemistry, University of Belgrade, Serbia 3 rd Prize: Maria Zoumpanioti, Institute of Biological Research and Biotechnology, National Hellenic Research Foundation, Athens, Greece 3 rd Prize: Irina Smeu, National Institute of Research & Development for Food Bioresources IBA Bucharest, Romania List of participants: Lecturers: 1. Theodore Sotiroudis, Greece 2. Raija Lantto, Finland 3. Biljana Škrbić, Serbia 4. Craig Faulds, Finland 5. Luc Saulnier, France 6. Mirjana Pešić, Serbia Oral presenters: 1. Vassiliki Papadimitriou, Greece 2. Nabiha Bouzouita, Tunisia 3. Abdelfatteh El Omri, Japan 4. Teresa Kowalska, Poland 5. Hubert Paelinck, Belgium 6. Eveline De Mey, Belgium 7. Elena S. Chernetsova, Russia 8. Łukasz Cieśla, Poland 9. Christophe Tistaert, Belgium 10. Georgios Skretas, Greece

4 11. Aleksandra Dimitrijević, Serbia 12. Alina Culetu, Romania 13. Miroljub Barac, Serbia Poster presenters: 1. Lore Dewulf, Belgium 2. Elena S. Chernetsova, Russia 3. Danka Bukvicki, Serbia 4. Ivana Prodić, Serbia 5. Maria-Theognosia Savvidou, Greece 6. Marta Olech, Poland 7. Alina Dobre, Romania 8. Ahmed Snoussi, Tunisia 9. Marija Petrović, Serbia 10. Ismahene Essaidi, Tunisia 11. Irina Smeu, Romania 12. Anja Gavrilović, Serbia 13. Ivan Pavićević, Serbia 14. Alina Cristina Bălea, Romania 15. Georgios T. Sotiroudis, Greece 16. Daniela Ringli, Germany 17. Marta Drozd, Poland 18. Maja Krstić, Serbia 19. Gabriel Mustatea, Romania 20. Maja Kozarski, Serbia 21. Marinela Šokarda Slavić, Serbia 22. Elena M. Pruteanu, Romania 23. Aleksandra Pavlović, Serbia 24. Hayet Ben Haj Koubaier, Tunisia 25. Jelena Vesić, Serbia 26. Milica Carević, Serbia 27. Maria Zoumpanioti, Greece 28. Ana Penezić, Serbia 29. Alexandra R. Decu, Romania 30. Jovana Stefanović, Serbia 31. Eveline De Mey, Belgium Scientific Committee 1. Dr. Dragana Stanić-Vučinić (President) 2. Prof. Dr. Tanja Ćirković Veličković 3. Prof. Dr. Miroslav Vrvić 4. Prof. Dr. Dusanka Milojkovic-Opsenica 5. Prof. Dr. Zoran Vujčić

5 6. Dr. Nataša Božić 7. Dr. Craig Faulds 8. Dr. Theodore Sotiroudis 9. Dr. Estelle Bonnin 10. Dr. Ivan Minkov Organizing Committee 1. Dr. Nenad Milosavić (President) 2. Dr Milan Nikolić 3. Jelena Radosavljević 4. Jana Ognjenović 5. Aleksandra Dimitrijević 6. Dušan Veličković 7. Marija Stojadinović 8. Jelena Vesić 9. Ivana Prodić 10. Maja Krstić CVs of lecturers: Theodore Sotiroudis, PhD, is director of Research in IBRB/ National Hellenic Research Foundation (Athens, Greece) and the group leader of the Enzyme and Synthetic Biotechnology Program of IBRB. He has more than 30 years of research experience in protein chemistry and enzymology and more than 120 publications, 64 of which are in peer reviewed international journals. During the last years, he has focused on Industrial Biotechnology: understanding of the effect of oxidative processes on the quality of virgin olive oil and other plant foods of Mediterranean Diet, as well as the production of active biomolecules from plant material, the culture of microalgae, aiming on the production of functional foods, nutraceuticals and cosmetics, and the production of biodiesel from non-edible seed oils and microalgae. Raija Lantto, PhD, works as a principal scientist and technology manager at VTT Technical research centre of Finland, Bio and process technology, Espoo, Finland. She heads a knowledge centre BIOPROCESSING with 120 people. Before coming to VTT she has worked more than 10 years in the enzyme industry. Her competence area is industrial enzyme applications with special expertise in protein modification. Her special expertise area is protein cross-linking enzymes and their structural and textural effects in various milk, meat and fish systems. She has more than 20 peer-reviewed publications and the same number of patents and patent applications related to enzymes and their application both in food and non-food sectors. Prof. Biljana Škrbić is a full professor at the Faculty of Technology, University of Novi Sad. She is founder and head of the Laboratory for Chemical Contaminants in the Food and Environment at the Faculty of Technology that is the only non-eu lab included in proficiency testing on Polycyclic aromatic hydrocarbons and mycotoxins in food organized by European

6 Commission. She is the author of 9 books, 400 articles, 75 articles in the leading international journals. Coordinator of the 9 international and 9 national projects, among which is the FP7 project CEFSER. Her research activity is focused on food safety and quality control, environment protection, development of analytical methods for chemical contaminants and residues in abiotic and biotic matrices, new food products based on major food crops with enhanced nutritive value, oil-petrochemical technology, application of chemometrics methods in chemical engineering and environment. Craig Faulds, PhD, is a Principal Scientist in the Bioprocessing Department at the Tecnical Research Centre of Finland. He joined VTT in April this year having spent the last 2 years in Madrid and the previous 21 years in the Institute of Food Research in Norwich, UK. He is responsible for coordinating research on the utilization of organic side-streams and his interest is in the use of enzymes to modify and valorize hemicellulose and lignin. His research activity is focused on plant cell wall disassembly using enzymes, feruloyl esterases, enzyme synergy in the hydrolysis of hemicellulose, use of enzymes in plant biomass utilisation, utilisation of agri-food wastes for added-value food and non-food products, utilisation of food wastes for biofuel, isolation, breakdown and characterization of hemicellulose. Luc Saulnier, PhD, is senior scientist at the INRA research center of Nantes, France, and is working in the Research Unit: Biopolymers, Interactions Assemblies.. He received his PhD degree in plant physiology in 1987 from Paul Sabatier University (Toulouse, France). His research activitiy is mainly focused on the structure and functional properties of cell wall polysaccharides from plant and especially cereal grains. He is author of about 100 original peer reviewed international publications and 2 patent applications. He has collaborated with a number of international partners within EU Framework Programmes. Mirjana Pešić, PhD, is assistant at Faculty of Agriculture, University of Belgrade. She received her PhD in Biochemistry, Faculty of Chemistry, University of Belgrade. The scientific research is focused on food proteins, biochemical transformation during food processing and functional properties of food. She was participated as researcher in 6 scientific project governed by Ministry of Science, Republic of Serbia and one international project governed by Swiss National Science Federation SCOPES. Currently, she is a leader of subproject of Project in the frame of Programme for technological development.

7 2 nd Workshop Program Day 1: 18 th October, :00 9:15 Opening of the 2 nd FCUB-ERA Workhop 9:00 9:15 Ž. Tešić: Opening of the 2 nd FCUB ERA Workshop 9:15 10:45 Session 1: Plant food chemistry and biochemistry Chairperson: Ž. Tešić, C. Faulds 9:15 10:00 Invited lecture: Minor Components in Virgin Olive Oil: Functional and Structural Aspects Sotiroudis Theodore, National Hellenic Research Foundation, Institute of Biological Research & Biotechnology, Athens, Greece 10:00 10:15 Oral presentation: Olive oil microemulsions: a biomimetic model to simulate aspects of the digestion process in the gastrointestinal tract Vassiliki Papadimitriou, National Hellenic Research Foundation, Institute of Biological Research & Biotechnology, Athens, Greece 10:15 10:30 Oral presentation: Chemical composition, Antioxidant and Antimicrobial activities of essential oils from Tunisian aromatic plants Nabiha Bouzouita, High School of Food Industries, Tunis, Tunisia 10:30 10:45 Oral presentation: Neuro-protective properties of Tunisian R. officinalis Abdelfatteh El Omri, Graduate School of Life and Environmental Sciences & Alliance for Research on North Africa, University of Tsukuba, Japan 10:45 11:15 Coffee break and poster session 11:15 12:45 Session 2: Animal food chemistry and biochemistry Chairperson:, L. Saulnier, B. Škrbic 11:15 12:00 Invited lecture: Cross-linking enzymes in food prosessing: effects on structure, texture and stability of protein-based foods Lantto Raija, VTT Bio and process technology, Finland 12:00 12:15 Oral presentation: The occurrence of N-nitrosamines in heated cured meat. Part I. Methodology and analysis Teresa Kowalska, Institute of Chemistry, University of Silesia, Poland 12:15 12:30 Oral presentation: The occurrence of N-nitrosamines in heated cured meat. Part II. Food safety aspects Hubert Paelinck, Catholic University College Ghent, Belgium 12:30 12:45 Oral presentation: The occurrence of N-nitrosamines in dry fermented sausages: biogenic amines as possible precursors Eveline De Mey, Catholic University College Ghent, Belgium 12:45 14:15 Lunch 14:15 15:45 Session 3: Food analysis

8 Chairperson: D. Milojković-Opsenica, T. Sotiroudis 14:15 15:00 Invited lecture: Mycotoxins in cereal-derived products: occurrence and intakes in selected Serbian commodities Biljana Škrbić, Faculty of Technology, University of Novi Sad, Serbia 15:00 15:15 Oral presentation: The coupling of HPTLC with DART mass spectrometry and its perspectives in food analysis Elena S. Chernetsova, National Research Centre Kurchatov Institute, Moscow, Russia 15:15 15:30 Oral presentation: Simple TLC benchtop bioassays in the analysis of plant extracts as potential nutraceutical s sources Łukasz Cieśla, Medical University of Lublin, Poland 15:30 15:45 Oral presentation: Citri reticulatae pericarpium: exploratory analysis and discrimination amongst Citrus species Christophe Tistaert, Department of Analytical Chemistry and Pharmaceutical Technology, Vrije Universiteit Brussel, Brussels, Belgium 15:45 17:00 Coffee break and poster session Day 2: 19 th October, :00 12:00 Session 4: Food Biotechnology Chairperson: M. Vrvić, N. Božić 9:00 9:45 Invited lecture: Waste or High-Value: How can we use food by-products? Craig B. Faulds, VTT Technical Research Centre of Finland, Espoo, Finland 9:45 10:30 Invited lecture: Cereal dietary fibers, technological impact and nutritional effects Luc Saulnier, Biopolymères, Interactions, Assemblages, INRA, Nantes, France 10: 30 11:00 Coffee break and poster session 11:00 11:15 Oral presentation: Engineered bacteria for the detection, discovery, and assessment human hormones Georgios Skretas, Institute for Biological Research and Biotechnology, National Hellenic Research Foundation, Athens, Greece 11:15 11:30 Oral presentation: Single step isolation of lipase A from Candida antarctica DSM Aleksandra Dimitrijević, Faculty of Chemistry, University of Belgrade, Serbia 11:30 11:45 Oral presentation: Study regarding the behavior of palm oil used for frying at controlled temperature Alina Culeţu, National Institute of Research & Development for Food Bioresources IBA Bucharest, Romania 11:45-12:00 Oral presentation: Effect of limited hydrolysis by hymosin on functional properties of pea protein isolate Barać Miroljub, University of Belgrade, Faculty of Agriculture, Belgrade-Zemun 12:00 12:45 Session 5: Dairy industry Chairperson: R. Lantto, D. Stanić-Vučinić 12:00 12:45 Invited lecture: Micellar/Serum distribution of heat-induced whey protein/κ-cn complexes in caprine milk Mirjana B. Pešić, Faculty of Agriculture, Institute of Food Science and Technology, Belgrade, Serbia 12:45 14:15 Lunch 14:15 14:45 Award ceremony Closure of the workshop 17:00 19:00 Coctail

9 2 nd FCUB ERA Workshop Food Chemistry and Biotechnology Belgrade, 18 th and 19 th October 2011.

10 2 nd FCUB ERA Workshop Prof. Dr. Živoslav Tešić, President of the 2 nd FCUB ERA Workshop Scientific Committee: Dr. Dragana Stanić-Vučinić (President) Prof. Dr. Tanja Ćirković Veličković Prof. Dr. Miroslav Vrvić Prof. Dr. Dusanka Milojkovic-Opsenica Prof. Dr. Zoran Vujčić Dr. Nataša Božić Dr. Craig Faulds Dr. Theodore Sotiroudis Dr. Estelle Bonnin Dr. Ivan Minkov Organizing Committee: Dr. Nenad Milosavić (President) Dr Milan Nikolić Jelena Radosavljević Jana Ognjenović Aleksandra Dimitrijević Dušan Veličković Marija Stojadinović Jelena Vesić Ivana Prodić Maja Krstić

11 Content: 1. Session 1: Plant food chemistry and biochemistry 2. Session 2: Animal food chemistry and biochemistry 3. Session 3: Food analysis 4. Session 4: Food biotechnology 5. Session 5: Dairy industry 6. List of poster presentations

12 Session 1: Plant food chemistry and biochemistry Invited lecture: Minor Components in Virgin Olive Oil: Functional and Structural Aspects Theodore G. Sotiroudis, Aristotelis Xenakis, Vassiliki Papadimitriou Institute of Biological Research and Biotechnology, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, Athens 11635, Greece Olive tree (Olea europea) has been cultivated for thousands of years in countries surrounding the Mediterranean Sea and it still remains a typical Mediterranean crop. Virgin olive oil (VOO) is unique among the vegetable oils because it can be consumed without any refining. Olive oil is a major constituent of the health-promoting Mediterranean diet. Its most known benefit is the reduction of cardiovascular morbidity and mortality and increase in longevity. It also has been found to reduce some type of cancers. Additionally, metabolic syndrome factors and mental health conditions might also be improved by following this type of diet. US FDA has given its backing to the claim that olive oil can lower the risk of heart disease due to its monounsaturated fat. Nevertheless, scientific evidence, suggests that it is olive oil's minor component content (it includes mono- and diacyl glycerols, free fatty acids, phenolics, sterols, tocopherols, squalene, phospholipids and proteins) rather than its fatty acid profile, that is responsible for at least some of its health benefits. In this respect, EFSA Panel on Dietetic Products, Nutrition and Allergies concludes that a cause and effect relationship has been established between the consumption of olive oil polyphenols (standardised by the content of hydroxytyrosol and its derivatives) and protection of LDL particles from oxidative damage. Minor components also greatly affect quality and structure of VOO, which is known to depend on the extraction conditions. The presence of the minor components, which are either amphiphilic or even hydrophilic, together with some remaining moisture, induces colloidal association within the lipophilic triglyceride phase. These local organizates host proteins/enzymes and antioxidants that preserve their activity influencing the quality and stability of the edible oil. Of special interest is the unfiltered VOO, known as veiled VOO (VVOO), very rich in minor constituents, the optimization of which as regards its stability is not yet determined. Understanding composition and structure of the colloidal nanodispersions of VOO and unfiltered VVOO, is critical for the quality of the product offered to the consumers, thus providing their full health benefits. The lecture describes results of our research group concerning the effect of olive oil minor components on biochemical and biophysical properties of VOO/VVOO nanodispersions and emulsions or biocompatible microemulsions formulated with olive oil. Observations made could be of interest in improving the quality and health benefits of this edible oil product and in the perspective of future biotechnological applications of olive oil based microemulsions.

13 Oral 1.1. Olive oil microemulsions: a biomimetic model to simulate aspects of the digestion process in the gastrointestinal tract A. Kyriazi 1,2, V. Papadimitriou 1, V.J. Sinanoglou 2, T.G. Sotiroudis 1, A. Xenakis 1 1 Institute of Biological Research & Biotechnology, National Hellenic Research Foundation, 48, Vassileos Constantinou Ave., 11635, Athens, Greece 2 Department of Food Technology, Technological & Educational Institution of Athens, Egaleo, Greece Bioinspired water-in-oil (w/o) microemulsions composed of olive oil as the continuous phase, lecithin as surfactant, propanol as cosurfactant and water as the dispersed phase were used as a biomimetic model to simulate aspects of the digestion process in the gastrointestinal tract [1]. For this purpose two well-studied enzymes of the digestion process, exhibiting though different specificities, namely trypsin and alkaline phosphatase, were examined. Trypsin and alkaline phosphatase are secreted in the small intestine and are involved in the digestion of food proteins and lipids, respectively. Trypsin, a serine protease excreted by the pancreas, was incorporated in the aqueous core of olive oil based microemulsions and its activity towards hydrolysis of a synthetic substrate, namely lysine p-nitroanilide, was examined. The hydrolytic reaction was followed at ph and temperature conditions corresponding to human small intestine conditions (ph 8.5 and 36.6 C) and kinetic constants were calculated. Then, several antioxidants that naturally occur in virgin olive oil were added in the reaction system and their effect on the proteolytic reaction was investigated. Except from gallic acid, o-coumaric acid and squalene that caused a decrease of enzymatic activity, all other olive oil polyphenols tested, seem to have the opposite effect. More specifically, when caffeic acid, protocatechuic acid, p-coumaric and o- coumaric acids were added, enzymatic activity was enhanced. Alkaline phosphatase, a membrane bound enzyme, possibly having a biological role related to the digestion and absorption of lipids, was also incorporated in the aqueous core of olive oil based microemulsions. Alkaline phosphatase activity was monitored towards hydrolysis of p-nitrophenyl phosphate. In the presence of all the antioxidant compounds mentioned above, enzyme activity was inhibited. The development of an in vitro digestion model for hydrolases suggested in the present study may on one hand improve our understanding of food digestion process and on the other could potentially lead to the production of food with better functionalities References 1. Papadimitriou, V., Sotiroudis, T. G. & Xenakis, A. (2007). Olive Oil Microemulsions: Enzymatic Activities and Structural Characteristics. Langmuir 23,

14 Oral 1.2. Chemical composition, Antioxidant and Antimicrobial activities of essential oils from Tunisian aromatic plants Nabiha Bouzouita, Ahmed Snoussi, Hayet Ben Haj Koubaier, Ismahene Essaidi, Faten Kachouri and Mohamed Mancef Chaabouni High School of Food Industries, 58, Avenue Alain Savary, 1003 Tunis, Tunisia The essential oils, isolated by hydrodistillation, from the aerial parts of Thymus capitatus, Ocimum basilicum, Myrtus communis, Laurus nobilis, Lavandula stoechas, Ruta graveoleus, Junipreus phoenicea, Mentha pulegium, Citrus bergamia risso, Cyperus rotendus, and three varieties of Eucalyptus camaludulensis, rudis and lehmanii, were analyzed by gas chromatography (GC) and gas chromatography coupled to mass spectrometry (GC-MS). The highest oil yield was obtained from Citrus bergamia risso (9.7%), while the lowest one was obtained from Ocimum basilicum (0.2%). The different oils consisted three main groups of constituents named monoterpenes hydrocarbons, oxygenated monoterpenes and sesquiterpenes. Monoterpenes hydrocarbons were dominant in Myrtus communis, Junipreus phoenicea, Citrus bergamia risso oils (68.3, and 66.37%, respectively), the other essential oil were dominated by oxygen-containing monoterpenes, from 59.39% to 92.40%. The essential oils investigated, exhibited good antioxidant activities when tested by DPPH free radical-scavenging ability and bleaching β-carotene in linoleic acid system. Evaluation of antimicrobial activity of the essential oils, against different microorganisms: Escherchia coli, Pseudomonos aeruginosa, Klebsiella pneumonia, Salmonella enteritidis, Staphylococcus aureus, Streptococcus A, Candida albicans and Geotrichum candidum, was assessed by submerged culture method and measurement of determination of minimum inhibitory concentration. The results of antimicrobial assays indicated that all the tested microorganisms were affected. The isolated essential oils have potential for development as natural antimicrobial and antioxidant agent. Keywords: Tunisian aromatic plants, essential oils, chemical composition, antioxidant activity, antimicrobial activity.

15 Oral 1.3. Neuro-protective properties of Tunisian R. officinalis Abdelfatteh El Omri 1,2,3*, junkyu Han 1,2, Manef Ben Abdrabbah 4, Hiroko Isoda 1,2 1 Graduate School of Life and Environmental Sciences, 2 Alliance for Research on North Africa (ARENA), University of Tsukuba, Tennodai, Tsukuba City, Ibaraki , Japan. 3 Research Institute of Biomolecule Metrology Co. Ltd Enokido, Tsukuba city, Ibaraki , Japan. 4 Unité de Recherche Physico-chimie et Moléculaire: Institut Préparatoire aux Etudes Scientifiques et Techniques IPEST, La Marsa, 2070 Tunis Tunisia * omriabdel@ribm.co.jp Rosemary (Rosmarinus officinalis), a member of Lamiaceae family, is an herbal spice native to Mediterranean basin. For long time, this plant was used in Mediterranean cuisine not only to improve or modify the flavor of food, but also to avoid its deterioration due to its antimicrobial and antioxidant activities. Traditionally, R. officinalis has a very old reputation for strengthening memory, and has been used as a symbol for remembrance. Antioxidant and neuroprotective effects are among the medicinal properties attributed to this plant. However, there is a lack of biological experimental confirmation for the traditional use of the plant. Therefore, these studies allowed us to observe the benefits of rosemary consumption to the neuronal system. Our findings showed that R.officinalis treatment significantly induced neurite outgrowth extension, enhanced cholinergic activities, and some protein marker of neuronal differentiation in PC12 cells. Such activities were dependent on plant growing ecosystem. Deep investigation of molecular mechanism using Proteomics and RT-PCR approach, demonstrated that R.officinalis polyphenols modulate neurotransmitters synthesis and decrease cellular stress in neuronal cells.

16 Session 2: Animal food chemistry and biochemistry Invited lecture: Cross-linking enzymes in food prosessing: effects on structure, texture and stability of protein-based foods Dilek Ercili-Cura, Riitta Partanen, Martina Lille, Johanna Buchert and Raija Lantto VTT Technical Research Centre of Finland, PO Box. 1000, FIN VTT, Finland ( Food structure is an essential sensory property. It affects consumer choices and food stability. Food texture can be tailored in many ways, e.g. by addition of hydrocolloids and thickeners or by creating covalent crosslinks between food biopolymers. In this presentation the special emphasis is on the enzymatic crosslinking and its impact on food structure and texture. Crosslinks can be introduced to food matrices by chemical, enzymatic, and physical means, but enzymatic crosslinking is an attractive option because of the high specificity of enzymes. The crosslinking can be a result of direct enzymatic catalysis of crosslink formation or occur indirectly by enzymatic production of a crosslinking agent, such as H2O2, which in turn is able to oxidize reactive structures with subsequent crosslink formation. Proteins have several reactive groups for crosslinking enzymes, such as glutamine, lysine, tyrosine, and cysteine residues. Extent of crosslinking reactions is dependent mainly two factors: optimum activity and stability conditions (temperature, ph, exclusion of inhibitors, etc.) for the related enzyme and the morphological state of the substrate molecule. A number of studies have shown that nonglobular proteins are more easily accessible to enzyme active sites than globular proteins. E.g. caseins are excellent substrates due to their flexible and open tertiary structure. On the other hand, globular whey proteins in their native form are quite poor substrates for enzymatic catalysis. Utilization of milk protein products in food is dependent on their physicochemical and functional properties. In this sense, extensive knowledge on complex structure of various milk proteins is needed in order to be able to tailor them toward better functionality. Enzymes capable of modifying textural and water-binding properties of milk proteins by creating inter- or intramolecular covalent bonds may be exploited to fabricate milk products with acceptable texture in spite of low fat or protein content. By using crosslinking enzymes, functional properties such as texture and water holding of meat products can be modified. The target molecule for crosslinking is the myofibrillar protein myosin. Hitherto, transglutaminase (TG) has been the main crosslinking enzyme studied in meat applications, and it is also industrially used. In the meat industry, there is one distinct application in which crosslinking enzymes can markedly boost the manufacturing process and add value to meat of poorer quality. This application is restructuring, i.e., stabile gluing of meat pieces together. In addition to restructuring, TG is successfully exploited in improving textural properties of heated meat products such as hams and sausages. Structural and textural effects of enzymatic crosslinking in milk and meat systems are discussed in the presentation.

17 Oral 2.1. The occurrence of N-nitrosamines in heated cured meat. Part I. Methodology and analysis Gabriela Drabik-Markiewicz 1, Eveline De Mey 2, Hubert Paelinck 2, Teresa Kowalska 1 1 Institute o Chemistry, University of Silesia, 9 Szkolna Street, Katowice, POLAND 2 Research Group for Technology and Quality of Animal Products, Catholic University College Ghent, Gebroeders Desmetstraat 1, B-9000 Ghent, Belgium Sodium nitrite and sodium nitrate are used as curing agents in meat and they are important not only as preservatives, but also for the color and flavor formation Unfortunately sodium nitrite also plays a considerable role in formation of the carcinogenic volatile N- nitrosamines. Appearance of these compounds in meat products depends on various different parameters associated with preparation, storage, and thermal processing of meat. Different precursors of NPYR have been suggested in the literature, including proline, collagen, putrescine, spermidine, and pyrrolidine. The aim of presented research was to determine the chemical role of proline, hydroxyproline, pyrrolidine, putrescine, cadaverine, spermidine, and spermine in the N- nitrosamine formation during the heating of the cured meat products with or without the addition of sodium nitrite, in order to define the process conditions that can be responsible for an increased N-nitrosamine formation. The tested meat samples were prepared according to a cooked ham model. They contained changing amounts of sodium nitrite, 1000 mg kg -1 proline, hydroxyproline, putrescine, cadaverine, spermidine or spermine, or 10 mg kg -1 pyrrolidine. The samples were heated for 30 minutes using different temperatures to mimic the industrial processes. Final step in the procedure of determination N-nitrosamines in the meat samples was their identification through a comparison of the retention times for the registered peaks with those for a series of standard ompounds. The N-nitrosamines of interest were analyzed and identified by thermal energy analyzer (TEA) which is an extremely selective gas-chromatographic detector with low detection limits for N-nitroso compounds. An appearance of the five volatile N-nitrosamines was anticipated in the processed meat samples and calibration curves were produced. However, when applying the above described meat processing procedure, only three N-nitrosamines were detected in the processed products, i.e., NDMA, NPYR and NPIP. Upon the performed statistical evaluation of experimental results presented in this study, the importance of amino acids and biogenic amines, which are naturally present in raw meat, was confirmed. The process conditions considered in this study can be used as an indication for the meat industry what working parameters have to be avoided.

18 Oral 2.2. The occurrence of N-nitrosamines in heated cured meat. Part II. Food safety aspects Gabriela Drabik-Markiewicz 2, Eveline De Mey 1, Teresa Kowalska 2, Hubert Paelinck 1 1 Research Group for Technology and Quality of Animal Products, Catholic University College Ghent, Gebroeders Desmetstraat 1, B-9000 Ghent, Belgium 2 Institute of Chemistry, University of Silesia, 9 Szkolna Street, Katowice, Poland Foodstuff often contain contaminants being formed during processing: acryl amide, polycyclic aromatic hydrocarbons, heterocyclic amines, volatile N-nitrosamines, Because their potential carcinogenic properties, the presence of these contaminants must be maximally avoided. N-nitrosamines, resulting from a reaction between a secondary amine and a nitrosating agens, can be provoked by the presence of biogenic amines, sodium nitrite and processing parameters. The aim of this study was to investigate the influence of the added amount of sodium nitrite (0-480 mg/kg) and the intensity of the heat treatment ( C) of a lean meat model on the formation of the N-nitrosamines, such as N-nitrosodimethylamine (NDMA), N- nitrosodiethylamine (NDEA), N-nitrosodibutylamine (NDBA), N-nitrosopiperidine (NPIP) and N-nitrosopyrrolidine (NPYR). In addition, the models were enriched with secondary amines, namely proline, hydroxyproline, pyrrolidine, putrescine, cadaverine, spermidine and spermine, to study their potential as N-nitrosamine precursors. The samples were analyzed according the method of Drabik-Markiewicz et al. (2009) using a gas chromatograph coupled to a thermal energy analyzer (GC-TEA). With the intention to estimate the risk on the occurrence of carcinogenic N-nitrosamines in heated cured meat, the obtained datasets were statistically subjected to ANOVA. Of the five investigated N-nitrosamines, only NDMA, NPIP and NPYR were detected, and moreover the detected amounts remained in general very low. Higher concentrations of NaNO 2 and higher meat processing temperatures resulted in an slightly increased NDMA level (maximal 0.3 µg/kg). However, none of the investigated amine precursor gave rise to higher NDMA levels, except under the harshest conditions putrescine could raise the NDMA formation. The NPYR formation was provoked only by proline at very intensive heating and addition of legally not allowed concentrations of sodium nitrite (>150 mg/kg). Cadaverine and spermidine could slightly influence the NPIP formation, but even at elevated temperatures and sodium nitrite concentrations the levels remained low. In conclusion, as long as the processing temperature is not exuberant and the sodium nitrite concentration is lower than lawfully permitted, no risk for N-nitrosamine formation during the heating of lean meat is expected.

19 Oral 2.3. The occurrence of N-nitrosamines in dry fermented sausages: biogenic amines as possible precursors Eveline De Mey 1, Lore Dewulf 1, Gabriela Drabik-Markiewicz 2, Teresa Kowalska 2, Hubert Paelinck 2 1 Research Group for Technology and Quality of Animal Products, Catholic University College Ghent, Gebroeders Desmetstraat 1, B-9000 Ghent, Belgium 2 Institute of Chemistry, University of Silesia, 9 Szkolna Street, Katowice, Poland Objectives The formation of carcinogenic N-nitrosamines results from the reaction of a nitrosating agent (NO + ) with an amine precursor. While nitrite is generally used in meat products, fermented meat can also offer biogenic amines and can be therefore a source of N-nitrosamines. In this study the residual nitrite and nitrate, together with biogenic amines and N-nitrosamines were determined, to examine the safety of commercially available fermented sausages. Materials and Methods MAP-packed dry fermented sausages were obtained from 4 different supermarkets and stored at 7 C until end-of-shelf life. Biogenic amines, NO 2 - and NO 3 - were analyzed by HPLC-UV. The N-nitrosamines were detected by GC-TEA. The collected data was examined by Predictive Analysis Software (PASW Statistics , SPSS Inc.) and the Spearman s correlation coefficients were calculated. Results and conclusions The residual nitrite level was in 87 % of the samples less than 50 mg/kg (directive 95/2/EC). At end-of-shelf life the putrefactive biogenic amines putrescine and cadaverine remained usually low. Only in a few cases the levels increased to 316 mg/kg, resp. 641 mg/kg, which indicated a risk for human health since both biogenic amines aggravate histamine and tyramine food poisoning. Exceptionally N-nitrosamines were detected. Even more, no correlation between the biogenic amine accumulation and the presence of N-nitrosamines was recognized. Although the N-nitrosamine concentrations remained low in dry fermented sausages, the relationship between the residual nitrite level and N-nitrosodimethylamine (p<0.05), N-nitrosodibutylamine (p<0.01), N-nitrosopyrrolidine (p<0.05) and N-nitrosomorpholine (p<0.05) was confirmed.

20 Session 3: Food analysis Invited lecture: Mycotoxins in cereal-derived products: occurrence and intakes in selected Serbian commodities Biljana Škrbić Faculty of Technology, University of Novi Sad, Bulevar cara Lazara 1, Novi Sad, Republic of Serbia Wheat-based products play an essential role in the Serbian diet and constitute one of its most important characteristic features. Namely, in Serbia, human consumption of wheat-based products is greater than of products made from other cereals. The most important wheat-based products are wheat flour, bread, pasta, pastry and cookies, which average consumption figures in 2011 (Statistical Office of the Republic of Serbia, 2011) are: 50.0, 275.5, 11.1, 16.7 and 9.5 g per person per day, respectively. These foodstuffs represent approximately 26% of Serbian market basket (Statistical Office of the Republic of Serbia, 2011). Till now, there have been no available data on consumer exposure to mycotoxins in Serbia, even though information of toxin levels in foodstuffs have been sporadically published. The main objective of this study was to: identify and quantify the occurrence of 11 principal mycotoxins in wheat flour collected from the Serbian markets in order to estimate the exposure to these toxins through consumption of wheat-based products (flour, bread, pasta, pastry and cookies) by the Serbian population. Intakes were calculated for average consumers among adults and children and then compared with the tolerable daily intake (TDI) proposed by Scientific Committee on Food of the European Union. The wheat flour samples were prepared by simple one-step method and analyzed by ultra-high performance liquid chromatography with heated electrospray ionization triple quadrupole mass spectrometry (UHPLC/HESI-MS/MS). Of all analyzed samples, 86.67% of the samples contained deoxynivalenol (DON) over the limit of detection method (0.3 μg/kg), followed by zearalenone (ZON) and T-2 toxin, with frequency of occurrence as follows 33.33% and 26.67%, respectively. Aflatoxins (AFs), ochratoxin A (OTA), HT-2 toxin, fumonisins B1 (FB1) as well as B2 (FB2) were below the limit of detection. This is the first report on the simultaneous occurrence of these mycotoxins in wheat flour from the Serbian market, and this information is of high priority in order to protect the consumer s health from the risk of exposure to these toxins. Acknowledgment The results presented here are obtained within the project "Estimation of chemical safety of market basket and population dietary exposure" supported by Secretariat for Science and Technological Development of the Province of Vojvodina and coordinated by Prof. B. Škrbić.

21 Oral 3.1. The coupling of HPTLC with DART mass spectrometry and its perspectives in food analysis Elena S.Chernetsova *(1,2), Gertrud E. Morlock (1) (1) Institute of Food Chemistry, University of Hohenheim, Garbenstrasse 28, Stuttgart (Germany) (2) On leave from: National Research Centre Kurchatov Institute, Akademika Kurchatova sq. 1, Moscow, and People s Friendship University of Russia, Miklucho-Maklaya str. 6, Moscow (Russia) The benefit of Direct Analysis in Real Time mass spectrometry (DART-MS) as compared to conventional MS techniques is the absence of the need for sample preparation, as the ionization occurs directly from the surface of solid or liquid samples [1, 2]. Due to this, the online combination of DART mass spectrometry with high-performance thin-layer chromatography does not require any extraction dithering the spot and distorting its composition. The possibilities of the TLC/HPTLC-DART-MS combinations were demonstrated in some publications [3-7], using only a small number of analytes. However, in early studies due to the fixed, horizontal supply of the gas flow from the DART source to the MS inlet, the HPTLC/TLC plates were introduced manually as cut strips, which resulted in low repeatability. Recently, a new version of the DART ion source was suggested, which allowed adjusting the angle of the DART gas stream and the use of a motorized rail. The angled source should significantly extend the general capabilities of DART-MS due to the introduction of and access to wide surfaces. In order to select the most favorable conditions for DART-MS analysis, proper positioning of samples is important, therefore a simple and cheap technique for the visualization of the impact region of the DART gas stream onto a substrate was developed by us based on the chemical reaction on a filter paper or TLC plate upon heating [8]. A filter paper or TLC plate, previously loaded with the analyte, was immersed in a derivatization solution. On this substrate, owed to the hot DART gas impact, the reaction to a colored product occurred. Especially for scanning a whole sample track by TLC/HPTLC-DART-MS, such a visualization approach is useful due to the possibility for adjusting the coordinates of DART ion source in an optimal way. The new approaches arising from these studies were applied for the analysis of real samples, including honey and propolis extracts. This work was financially supported within the joint program of DAAD and the Ministry of Education and Science of the Russian Federation Mikhail Lomonosov - The development of a scientific potential of a higher school ( ), project # / References 1. R. Cody, J. Laramee, H. Dupont Durst, Anal. Chem. 77, 2005, E. Chernetsova, G. Morlock, Mass Spectrom. Rev. 80, 2011, G. Morlock, W. Schwack, Anal. Bioanal. Chem. 385, 2006, A. Alpmann, G. Morlock, J. Sep. Sci. 31, 2008, G. Morlock, Z. Ueda, J. Chromatogr. A 1143, 2007, E. Dytkiewitz, G. Morlock, J. AOAC Int. 91, 2008, N. Smith, M. Domin, L. Scott, Org. Lett. 10, 2008, E. Chernetsova, A. Revelsky, G. Morlock, Rapid Commun. Mass Spectrom. 2011, in press

22 Oral 3.2. Citri reticulatae pericarpium: exploratory analysis and discrimination amongst Citrus species Christophe Tistaert, Yvan Vander Heyden Department of Analytical Chemistry and Pharmaceutical Technology, Vrije Universiteit Brussel (VUB), Laarbeeklaan 103, B-1090 Brussels, Belgium, Nutraceuticals are becoming a very popular approach to treat or prevent diseases in many countries, including our Western society, making it a lucrative business worth billions of dollars. The main problem in this booming industry is the lack of quality control, needed to ensure the products quality and the patient safety. An example is the dried peel from the mature fruits of Citri reticulatae Blanco and its cultivars. This herbal product, also called Chen Pi, is often used in traditional Chinese medicine to eliminate phlegm and strengthen the spleen. While the Chinese Health Department only requires Citri reticulatae pericarpium samples to contain at least 3.5% of hesperidine, most citrus species meet this criterion. Other problems include the existence of mixed peels and coupled herbs : i.e. contamination with other citrus species and other herbal samples of the same plant source, respectively. To detect adulterations and contaminations, a HPLC methodology was developed for fingerprint analysis of citrus samples. The data set was recorded in three different stages considering: (1) samples obtained as Citri reticulatae pericarpium, (2) potential mixed peels and coupled herbs samples, and (3) dried peels of other citrus species. In a first data analysis step, an exploratory analysis was performed on the developed data sets using Principal Component Analysis. For the samples bought as Citri reticulatae pericarpium, the PC1-PC2 score plot revealed two clusters based on the sample preparation procedure: a cluster of samples obtained in ground form and extracted as they were and a cluster of samples obtained as pieces of peel and extracted after grinding ourselves. To eliminate the variation between the fingerprints not caused by differences in species, the sample preparation procedure was re-optimized and the new PC1- PC2 score plot did not separate both groups anymore. Once the HPLC optimizations were performed and the method validated, discrimination between the authentic PCR samples and all other samples was performed by probabilistic Discriminant Partial Least Squares. The established model was able to differentiate between both classes with a high reliability for each sample. Furthermore, evaluation of the score and loading plots of the model indicated nobiletin, tangeretin, naringin and hesperidin as important markers for the quality control of Citri reticulatae pericarpium.

23 Oral 3.3. Simple TLC benchtop bioassays in the analysis of plant extracts as potential nutraceutical s sources Łukasz Cieśla Department of Inorganic Chemistry, Medical University of Lublin, Chodżki 4a, Lublin, Poland Department of Biochemistry, Institute of Soil Science and Cultivation State Research Institute, Czartoryskich 8, , Puławy, Poland Thin-layer chromatography coupled with biodetection has become an important tool in screening natural samples for the presence of antimicrobial, antioxidant and free radical scavenging compounds, as well as those possessing the ability to inhibit selected enzymes (e.g.: acetyl- and butyrylcholinesterase, glucosidases, xanthine oxidase or tyrosinase). This technique can be of value in the search for compounds characterized with desired activity (so called effect directed analysis). As far as food chemistry is considered TLC bioassays may be used to screen samples for the search of potent antioxidants. Beneficial effects of polyphenolic free radical scavengers (phenolic acids and flavonoids) on human health is a well known phenomenon. Diet rich in antioxidants can be protective against cardiovascular disease as well as some neurodegenerative ailments, it may also inhibit carcinogenesis. TLC-DPPH test belongs to a group of the most frequently performed bioassays. Current researches at the Department of Inorganic Chemistry and the Department of Biochemistry are focused on the application of this simple test in the discovery of new potent free radical scavengers. The influence of different conditions on the observed results is also under studies in both Departments [1]. Several plant species have already been characterized as rich sources of antioxidants [2-3]. Individual compounds characterized with promising antioxidant properties were also isolated basing on the results of TLC-DPPH test. We are also working at the project aimed at adjusting TLC bioassays to screen volatile samples for the search of plant species with neuroprotective properties. The most recent results will be presented during this oral presentation. References [1] Ł. Cieśla, Thin-layer chromatography with biodetection in the search of new potential drugs to treat neurodegenerative diseases state of the art and future perspectives, Medicinal Chemistry, 2011, accepted for publication; [2] Ł. Cieśla, D. Staszek, M. Hajnos, T. Kowalska, M. Waksmundzka-Hajnos, Development of chromatographic and free radical scavenging activity fingerprints by thin-layer chromatography for selected Salvia species, Phytochemical Analysis 2011, 22, 59-65; [3] M. Olech, Ł. Komsta, R. Nowak, Ł. Cieśla, M. Waksmundzka-Hajnos, Application of a thinlayer chromatographic method with image processing to assess the antiradical activity of plant material, Food Chemistry, 2011, submitted to the journal.

24 Session 4: Food Biotechnology Invited lecture: Waste or High-Value: How can we use food by-products Craig B. Faulds VTT Technical Research Centre of Finland, Tietotie 2, Espoo, FI-02044, Finland Waste from agro-industrial food processing can amounts to millions of tonnes across Europe each year. Traditionally this material has gone to animal feed or composted to provide fertilizer. However, as industrial processes become centralised and enlarged due to consumer demands, more of these by-products ends up as landfill. There is great pressure from consumers and legislation for food producers to reduce disposal of by-product wastes which are biologically complex, environmental unfriendly and often microbiologically unstable. Nevertheless, this material is rich in high-value compounds and until it leaves the food production factory, can be still considered of food ingredient quality. Novel, hybrid methods and processes are sought to deconstruct plant-derived by-products into defined, marketable food and non-food products. Plant polymers form a complex matrix in which many health-influencing bioactives are contained. Before designing biorefining processes to obtain new value-chains from agri-food biomass, we require an understanding on polymers interact and how different technologies can be utilised to obtain information on changes in structure upon (bio)processing. We require processes from complete deconstruction of the polymeric layers to monomeric components, such as in the production of biofuels or flavour precursors, or regulated hydrolysis to retain the fine structures in, for example, functional ingredients. Cell wall polysaccharides contain different substitutions along their backbone other than sugars, such as methyl and acetyl groups, which influence the physico-chemical properties of the isolated polymers, and the ester-linked hydroxycinnamic acid, such as ferulate and p-coumarate, which can undergo oxidative coupling to form intra- and interpolymeric complexes. These complexes are implicated covalent linkages between the polysaccharides and protein or lignin. Reduction of by-product particles to micro- or nanosizes leads to changes in structure and surface area and brings out new characteristics that bulk materials do not possess. Changing the balance of soluble and insoluble polymers will lead to changes in product characteristics. Enzymes can be employed to facilitate extraction and modification of ingredients. Cross-linking can be applied to improve the texture and stability of products. Enzymes may also be used for the formation of hydrocolloids, thickeners and stabilizing agents for foams and emulsions, as well as being used to provide coating and composite materials with improved barrier properties.

25 Invited lecture: Cereal dietary fibers, technological impact and nutritional effects Luc Saulnier UR1268 Biopolymères, Interactions, Assemblages, INRA, F NANTES, Nantes Cedex 03, France Dietary fibre (DF) have significant benefits in reducing the incidence of a number of diseases such as cardiovascular disease, diabetes and certain cancers. Worldwide it is recommended to increase the consumption of DF up to 25-30g/day. In most European countries, the consumption of DF is below 20g/day, and cereal grains are probably the best source to increase DF consumption in human diet. Dietary fibres are mainly constituted by the cell wall polysaccharides of plants. However, depending on their origin in the grain, cell walls have very different chemical and physicochemical properties and therefore very different nutritional and technological effects. The state of art on the chemical structure and physico-chemical properties of cell wall polysaccharides from cereal grains will be presented. This knowledge is a key element to understand nutritional effects of DF according to their origin (part of the grain) or to cereal sources. Some examples on technological effects of DF in bread-making will be presented.

26 Oral 4.1. Engineered bacteria for the detection, discovery, and assessment human hormones Georgios Skretas Institute for Biological Research and Biotechnology, National Hellenic Research Foundation, Athens, Greece The nuclear hormone receptors comprise one of the largest classes of protein targets for drug discovery, as their function has been linked to a variety of serious diseases, including several forms of cancer. Identifying novel compounds with the ability to modulate the function of these targets could lead to the development of effective therapeutics. In vivo sensors of ligand binding have emerged as tools that can greatly accelerate the lead identification process, allowing new drugs to be discovered more rapidly and cheaply. We have developed a novel sensor of nuclear hormone binding in Escherichia coli by constructing a fusion of the ligandbinding domain of the human estrogen receptor with a thymidylate synthase enzyme (TS). Expression of this fusion protein in TS-deficient bacterial cells resulted in growth phenotypes that were dependent on the presence of estrogen. Subsequent replacement of the estrogen receptor with the ligand-binding domain of the human thyroid hormone receptor led to specific thyroid hormone-enhanced growth that was insensitive to estrogen. This biosensor was then challenged with a library of estrogen and thyroid hormone analogues, and it was observed that levels of cell growth correlate well with ligand-binding affinity. Remarkably, this simple biosensor was able to discriminate between agonistic and antagonistic activities, as combinations of estrogen agonists had an additive impact on cell growth, whereas known estrogen antagonists were found to neutralize agonist effects. Furthermore, the ability of this system to assist the discovery of new estrogen-mimicking compounds was validated by screening a small compound library, which led to the identification of two structurally novel estrogen receptor modulators and the accurate prediction of their agonistic/antagonistic biocharacter in human cells. The ability of our sensor to detect ligand binding and recognize pharmacologically critical properties arises from allosteric communication between the artificially combined protein domains, where different ligand-induced conformational changes in the receptor are transmitted to the catalytic domain and translated to distinct levels of enzymic efficiency. This is one of the first examples of an engineered enzyme with the ability to sense multiple receptor conformations and to be either activated or inactivated depending on the nature of the bound effector molecule. Our system constitutes a technique for facile selection of lead compounds with potential medical application.

27 Oral 4.2. Single step isolation of lipase A from Candida antarctica DSM Aleksandra Dimitrijević 1, Dušan Veličković 1, Dejan Bezbradica 2, Ratko Jankov 1, Nenad Milosavić 1 1 Faculty of Chemistry, University of Belgrade, Studentski trg 12, Belgrade, Serbia 2 Faculty of Technology and Metallurgy, Karnegijeva 4, Belgrade,Serbia Lipases (triacylglycerol ester hydrolases, EC ) are unique in catalysing the hydrolysis of fats into fatty acids and glycerol at the water-lipid interface and reversible the reaction in nonaqueous media. They are among the most popular industrial enzymes, which have been widely used in food, pharmaceuticals, detergents and cosmetics industry. Lipases have become an integral part of the modern food industry and are found in an increasing number of applications within the food industry, in particular, for inter-esterification of fats and oils, flavour development in dairy products, processing of foods such as meat, and in vegetables, fruits, baked goods and beer. Microbial lipases from bacteria, yeast and fungi are the main sources of current commercial lipases.yeast lipases have attracted much attention because they display exquisite chemselectivity, regio-selectivity and stereo-selectivity, and they are widely used in the food industry. Among yeasts, Candida antartica stand out as one of the best sources of most commercially available lipase preparations. Candida antarctica produces two different lipases, A and B. Although, lipase B (CAL B) is probably the mostly employed hydrolase in the biocatalysis field, lipase A (CAL A) atrracting increasing attentions because of its unique features among hydrolases: the high thermostability, the ability to accept tertiary and sterically hindered alcohols, the sn-2 recognition in hydrolysis of triglycerides and the selectivity towards trans-fatty acids. However, the high cost of these enzymes presents the major obstacle. Therefore, in the present investigation, a new, simple and inexpensive method has been developed, using hydroxyapatite (HAP) as a matrix for single step CAL A purification with the high yield and complete homogeneity. This protocol resulted in a 3.74-fold purification with 94.7% final recovery and 400,83 U/mg specific activity. The purified enzyme showed a single band of 45 kda on SDS PAGE after silver staining and exhibits optimal activity at 60 C.

28 Oral 4.3. Study regarding the behavior of palm oil used for frying at controlled temperature Alina Culeţu *, Marta Zachia, Elena-Marilena Pruteanu, Alexandra Decu National Institute of Research & Development for Food Bioresources IBA Bucharest, Romania, * alinaculetu@yahoo.com The aim of this study was to investigate the behavior and physical-chemical transformation of non-hydrogenated refined palm oil used for frying frozen French fries at controlled temperature. For comparison, there were performed in parallel, on the same working conditions and analysis, studies regarding the use of refined sunflower oil. Both types of oil were purchased from the Romanian market, their chemical composition being: for palm oil (saturated fatty acids: 43%, monounsaturated fatty acids: 45%, polyunsaturated fatty acids: 12%, vitamin E: mg/100g) and for sunflower oil (saturated fatty acids: 12%, monounsaturated fatty acids: 26%, polyunsaturated fatty acids: 62%, vitamin E: 50 mg/100g). Successive frying was conducted daily (for 13 days) using fryers, the working procedure consisting in: heating oil at C for 30 minutes, frying potatoes at C for minutes, and then cooling the oil for collecting samples in order to perform analysis (such as: acidity, peroxide index, color, content of conjugates dienes and trienes). The results of this study showed that palm oil presents a higher oxidative stability than sunflower oil during frying process, due to its lower value for peroxide index (6.4 meq/kg compared to 14.9 meq/kg for sunflower oil). The same property is sustained by the lower content of conjugates dienes and trienes formation, these being spectrophotometrically monitored in UV at fixed wavelengths (233 nm, respectively 268 nm). The palm oil color showed an increase of 2.28 times from the initial color, while for the sunflower oil an increase of 3.93 was observed. However, changes of oil color in repetitive frying do not affect color, taste and smell of fries. Palm oil presents an acidity almost double compared to sunflower oil in the last day of the study. The palm oil acidity showed an increase of about 2.6 times from the initial measurement, while for the sunflower oil an increase of 7.6 was observed. It can be estimated a time for repetitive use of palm oil for 40 or 80 hours (according to the maximum limit imposed for acidity, of 0.5%, respectively 1%, values that require total replacement of oil, according to some quality control regulations in processing). The results from this study showed that palm oil presents a better behavior regarding the frying at controlled temperature compared to sunflower oil.

29 Oral 4.4. Effect of limited hydrolysis by hymosin on functional properties of pea protein isolate Barac, M. 1, Cabrilo, S. 2, Stanojevic, S. 1, Pesic, M. 1 1 University of Belgrade, Faculty of Agriculture, Nemanjina 6, Belgrade-Zemun s: baracm@agrif.bg.ac.rs, mpesic@agrif.bg.ac.rs, sladjas@agrif.bg.ac.rs 2 High Technical School of Vocational Studies, Pozarevac, Nemanjina 2, Serbia; slavica.cab@sbb.rs For a long time enzymatic hydrolysis has been recognized as relatively simple and useful method for improving sensory and nutritive values of plant proteins. From the standpoint of safety, limited enzymatic hydrolysis is a most appropriate way for obtaining desirable functional properties such as gelling, foaming and emulsifying of plant based protein products. Protein of different plant sources such as soy protein, pea bean protein, nuts, peanuts was the object of limited enzymatic hydrolysis. Different enzymes including trypsin, papain, pepsin, and several commercial proteases with different activity were used. It is well known that the effect of enzymatic hydrolysis was determined by numerous factors such as type of enzyme, treatment conditions (enzyme-substrate ratio, reaction temperature, time of enzyme action, characteristics of substrate). Furthermore, in order to achieve optimal results hydrolysis must be carried out under strictly defined and controlled conditions. In this study the effects of limited hydrolysis on functional properties as well as on protein composition of laboratory-prepared pea protein isolates were investigated. Pea protein isolates were hydrolysed for 15, 30 and 60 minutes with recombined hymosin (Maxiren). Changes of pea protein composition were detected by polyacrilamide gel electrophoresis (PAGE) and by elestrophoresis under reducing conditions (SDS-PAGE). Also, the effect of enzyme on solubility, emulsifying and foaming properties at different ph values (3.0; 5.0; 7.0 and 8.0) was determined. Hymosin could be a very useful agent for improving of functional properties of isolates. This enzyme caused low degree of hydrolysis (3.9%-4.7%) but significantly improved functional properties of PPI, especially at lower ph values ( ). At these ph values all hydrolysates had better solubility, emulsifying ability and foaming stability, while longer-treated samples (60 min) formed more stable emulsions than initial isolates. Also, regardles of ph value, all hydrolysates had improved foaming ability. A moderate positive correlation between solubility and EAI (0.74) and negative correlation between solubility and foam stability (-0.60) as well as between SP and EAI (-0.77) were observed. Registered improvements of functional properties were result of partial hydrolysis of insoluble protein complexes. Keywords: partial hydrolysis, hymosin, isolate, functional properties.

30 Session 5: Diary industry Invited lecture: Micellar/Serum distribution of heat-induced whey protein/κ- CN complexes in caprine milk Mirjana B. Pešić, Miroljub B. Barać, Ognjen D. Maćej, Nikola M. Ristić, Slađana P. Stanojević, *Miroslav M.Vrvić Faculty of Agriculture, Institute of Food Science and Technology, Nemanjina 6, Belgrade, *Faculty of Chemistry and Department of Chemistry IChTM, Studentski trg 12-16, Belgrade, Serbia In most commercial dairy processes, thermal treatment of milk and dairy products is an essential operation aimed at both food safety and shelf life of the final product and improvement of functional properties of proteins. During thermal processing, the whey proteins, mainly β- lactoglobulin (β-lg) and α-lactalbumin (α-la), denature and aggregate with each other and κ- casein to form protein complexes that are known to have a marked effect on the technologicalfunctional properties of final product. In bovine milk, the heat-induced serum protein/κ-cn complexes are located partly at the surfaces of casein micelles as micellar-bound complexes and partly in serum phase of milk as soluble complexes. The amount of formed complexes, their composition and repartition between micellar and serum phase of milk depends of varies technological factors such as ph, temperature, milk protein concentration and salts. In the present study, the distribution of denatured whey proteins in serum and micellarbound complexes formed in thermally treated caprine milk at 90ºC during 10 minutes was investigated. Protein were fractionated using fractionation technique based on renneting and three electrophoretic techniques, SDS-R-PAGE, SDS-NR-PAGE and native PAGE, were used to obtained information on the characteristics of the milk. The obtained results indicated that intensive denaturation of caprine major whey proteins were occurred in heated caprine milk at natural ph (6,71). Upon heating, only 2,61% of the total β-lg and 3,83% of the total α-la were in the native state. Fractionation analysis of major caprine whey proteins was revealed that all denatured β-lg and α-la were located on the surface of micelles as micellar-bound complexes. These data could be very useful in understanding the formation of acid gels of caprine milk. Concerning that the soluble complexes can act as a bridging material in the acid gel network, the lack of soluble complexes in serum phase of heat-treated caprine milk could be one of the main reason of unsatisfactory structure and soft curd of yoghurt produced from pure goat milk.

31 Poster session P 1. Detection of probiotics in fermented meat products by using polymerase chain reaction Lore Dewulf 1,2, Leen Van Houdt 1, Hannelore De Maere 2, Eveline De Mey 2, Hubert Paelinck 2 1 Life Sciences, Catholic University College Ghent, Gebroeders Desmetstraat 1, B-9000 Gent, Belgium 2 Research Group for Technology and Quality of Animal Products, Catholic University College Ghent, Gebroeders Desmetstraat 1, B-9000 Ghent, Belgium According to the currently adopted definition by FAO/WHO (Food and Agriculture Organization /World Health Organization), probiotics are: "Live microorganisms which when administered in adequate amounts confer a health benefit on the host". The effects of probiotics can only be guaranteed if the bacteria survive both the production process and the passage through the digestive system. In the meat industry, dry fermented sausages are the most suitable products for the addition of probiotics. In fact, no high temperatures in means of cooking or baking are comprised in the production process. In this way probiotics and starters, used for acidulation or colour formation, can be jointly added to the meat batter. In this study the starter culture TEXEL SA- 306 (Lactobacillus sakei, Staphylococcus carnosus and Staphylococcus xylosus) is combined with Lyofast BGP 93 (Lactobacillus casei LC-01) or Lactobacillus paracasei LTH 2579 as probiotic starter culture. To evaluate the presence of the probiotics in the product, bacteria are identified by means of Polymerase Chain Reaction (PCR). The goal in this research is to translate DNA-identification of a starter culture or probiotics by PCR-techniques into a useful tool for the meat industry.

32 P 2. Planar Chromatography with Different Detection Techniques: the Ultrafast Quantitation of 5-Hydroxymethylfurfural in Honey Elena S.Chernetsova (1,2), Gertrud E. Morlock (1) (1) Institute of Food Chemistry, University of Hohenheim, Garbenstrasse 28, Stuttgart (Germany) (2) On leave from: National Research Centre Kurchatov Institute, Akademika Kurchatova sq. 1, Moscow, and People s Friendship University of Russia, Miklucho-Maklaya str. 6, Moscow (Russia) During the last 20 years planar chromatography has changed, from a method with a poor reputation to a standardized, reproducible, and quantitative method, which is completely automated and very flexible with a variety of possibilities of analyte detection [1]. Components of a sample can be detected on a TLC or HPTLC plate using multiple detection techniques. Planar chromatography approaches can be successfully applied to the analysis of complex samples, especially foods and drinks, biological samples and natural products. However, the number of publications in this field is still very limited. For example, no publications on quantitation of 5-hydroxymethylfurfural (HMF) in honey using HPTLC were found. HMF concentration is a very important factor reflecting the quality of honey. Nowadays quantitation of HMF in honey is traditionally performed using spectrophotometric determination after White or after Winkler or using HPLC methods [2]. However, the Winkler method is not recommended anymore because of carcinogenic reagents and low precision. The White method was also characterized with a high uncertainty for some sorts of honey. So, HPLC is today very often used for the quantitation of HMF in honey, and the duration of analysis is usually 30 minutes or even more. Other, more prompt, reliable and cost-effective methods for HMF quantitation are needed. To our opinion, modern planar chromatography approaches are perspective for prompt and cost-effective analysis of honey. The aim of our recent studies was quantitation of HMF in honey using different planar chromatography approaches. We propose the ultrafast determination of HMF in honey using HPTLC instead of the traditional HPLC. The HPTLC separation lasts only 5 minutes, and up to 23 honey samples can be analyzed simultaneously on the same plate, providing the increase of the analysis throughput in more than 20 times as compared to HPLC-based approach. Using the simplest sample preparation (just dissolving 1 g honey in 10 ml water), performing a 5-minute separation and scanning at 288 nm, it was possible to quantify HMF in honey at the level of 8 mg/kg or even lower, while the concentration of 5-hydroxymethylfurfural in honey should not exceed mg/kg, according to different regulations. The fast screening of HMF content in honey is possible using paper chromatography as the cheapest possible alternative. Different detection techniques, such as ESI-MS and DART-MS, were applied for the quantitation of HMF in honey as well, and the method comparison was performed. The respective results will be presented and discussed. This work was financially supported by the Council at the President of Russia (grant МК ). References 1. G. Morlock, W. Schwack, J. Planar Chromatogr. 20, 2007, M. Zappala, B. Fallico, E. Arena, A. Verzera. Food Control 16, 2005, 273.

33 P 3. Chemical composition and antimicrobial potential of Scapania nemorea extracts against food spoilage microorganisms Danka Bukvicki 1,2, Davide Gottardi 2, Lucia Vannini 2, Maria Elisabetta Guerzoni 2, Milan Veljic 1, Petar D. Marin 1 1 Institute of Botany and Botanical Garden Jevremovac, University of Belgrade, Faculty of Biology, Studentski trg,16, Belgrade, Serbia 2 Department of Food Science, University of Bologna, Via Fanin 46, Bologna, Italy The chemical composition of the three extracts (methanol, ethanol and ethyl-acetate) of Scapania nemorea was determined by solid phase micro extraction-gas chromatography mass spectrometry (SPME- GC/MS). The dominant compounds in S. nemorea extracts were aromadendrene (6.31%, 8.20% and 5.38), muurolene (3.46%, 5.18% and 3.21%), 2(1-cyclopent- 1-enyl methylethyl) cyclopentanone (8.09%, % and 6.85%) in methanol, ethanol and ethyl-acetate extract, respectively. The antimicrobial activity of S. nemorea extracts were evaluated against 10 food spoilage microorganisms using micro dilution method. Extracts were initially screened against three food pathogen bacteria Salmonella enteritidis, Escherichia coli and Listeria monocytogenes and seven spoilage yeasts (Saccharomyces cerevisiae, Zygossacharomyces bailii, Aerobasidium pullulans, Pichia membranifaciens OC 71, Pichia membranifaciens. OC 70, Pichia anomala CBS 5759 and Pichia anomala DBVPG 3003).The minimum inhibitory concentration (MIC) varied from mg/ml for bacterial strains, and from 0.2 to 3.0 mg/ml for yeast strains. In comparison with more studied essential oils as cinnamon, clove, lemon, rosemary oil, which presented against different bacterial species MIC ranging from mg/ml (Prabuseenivasan et al., 2006), these results seem encouraging. The methanol extract of S. nemorea was added to a real food system, i.e. a fruit beverage based on orange and apple. The experiment was based on a central composite design at 3 variables and 3 levels. The variables were: the inoculum level (2 to 4 LogCFU/ml) of a target organism S. cerevisae 635, the extent of the thermal treatment of 70 C ( minutes) and the concentration of methanol extract of S. nemorea (0.5 to 2 mg/ml). The experimental results showed that the presence of the extract had a synergic effect with thermal treatment in inactivating S. cerevisae. Moreover, the growth extent during storage was affected by the concentration of the Scapania extract. Keywords: Scapania nemorea, chemical composition, antimicrobial potential, micro dilution method, SPME-GC/MS, real food system

34 P 4. Modification of β-lactoglobulin using ultrasound in the presence of carbohydrates by non-enzymatic glycosyilation (glycation) in Maillard reaction Ivana Prodic, Luka Mihajlovic, Tanja Cirkovic Velickovic and Dragana Stanic-Vucinic Faculty of Chemistry, University of Belgrade, Studentski trg 16, Belgrade Maillard reaction is reaction of non-enzymatic browning by reaction of carbonyl group, especially reducing saccharides with compounds with free amino groups, such as amino acids and proteins. This reaction occurs during thermal food processing and its products are responsible for color, taste and flavor, which can be desirable or non-desirable depending of kind of food. It is well known that ultrasound field has unique chemical and physical effects generated by collapsing cavitation bubbles. However, there is a scarce of literature data about non-thermal effects of ultrasound on Maillard reaction. The only one described study of this effect, recently published, was done on simple model system glycine-maltose. However, until now there is no data about promoting Maillard reaction by ultrasound in protein-carbohydrate system. Therefore, the aim of this study was investigation of possibility Maillard reaction promotion by ultrasound in protein-saccharide solution. As model protein β-lactoglubulin, the main whey protein was treated with ultrasound in absence or in presence of saccharides, such as glucose, fructose, lactose, ribose, arabinose and pectin. The results of this study demonstrated for the first time that protein can undergo glycation by Maillard reaction during ultrasound treatment in presence of carbohydrates. Ultrasound treatment of BLG in presence of saccharides results in reduction of amino group content, increasing of BLG pi value, increasing in mass of monomeric BLG and BLG polymerisation. Mass spectrometry analysis of obtained BLG derivatives shows conjugation of one, or more, molecules of saccharides (with elimination of water molecule). The results of all experiments unequivocally demonstrate that ribose is the most efficient in BLG modification of saccharides used, avle to modify even 9 amino groups of lysine/arginine residues. Also, antioxidative capacity of BLG increased by its modification. Saccharides the most efficient in glycation generated derivatives with higher antioxidative activity indicating that antioxidative capacity depends of glycation extent. In food industry modification of proteins by Maillard reaction caused by ultrasoud can have positive or negative effects on quality and desirable properties of food products implying importance of controlled ultrasound application in food systems containing proteins and saccharides. On the basis of obtained results it can be concluded that ultrasound, under conditions applied in this study, promoted mostly early stage of Maillard reaction without significant BLG structure changes. It seems that by proper choice of experimental conditions (ultrasound intensity, exposure time, maintained temperature, ph, concentration and protein/saccharide...) ultrasound induced Maillard reaction, could be much easier controlled compared to thermal induced.

35 P 5. Antioxidant activity of phycocyanobilin isolated from Spirulina sp. Milan NIKOLIĆ 1,2, Maria-Theognosia SAVVIDOU 3, Vassiliki PAPADIMITRIOU 1, and Theodore G. SOTIROUDIS 1 1 Institute of Biological Research and Biotechnology, National Hellenic Research Foundation, Athens, Greece 2 Department of Biochemistry, Faculty of Chemistry, University of Belgrade, Serbia 3 School of Chemical Engineering, National Technical University of Athens, Greece Spirulina, now named Arthrospira, is a microscopic and filamentous cyanobacterium, belonging to blue-green algae, the most primitive photosynthetic organisms. It has a long history of use as a safe food lacking toxicity due to the high quality and quantity (50-70% of its dried weight) of its protein. The major protein constituent of Spirulina with significant health effects is the phycobiliprotein phycocyanin C (PC), which contains linear tetrapyrrole prosthetic groups (phycocyanobilin - PCB) covalently linked to the apoprotein. PC, which has been widely used as a naturally occurring blue colorant for food additive purposes, expresses significant antioxidant, and radical scavenging properties. Part of these properties may by due to the participation of PCB. Since common tests for the assessment of antioxidant activity are based on the determination of optical absorption or fluorescence spectral changes of specific chemical reagents, their application for the estimation of the antioxidant capacity of PCB is complicated due to the development of parallel PCB spectral changes during the antioxidant reaction assay. In those cases, the only reliable alternative methodology is the use of Electron Paramagnetic Resonance (EPR) spectroscopy for following radical scavenging activity of PCB. In the present study, various spectrophotometric methods were used for characterization of antioxidant activity of PCB prepared by methanolysis from partially purified PC. These included: (i) iron (III) reducing capacity; (ii) total antioxidant capacity measured by phosphomolybdenum method, and (iii) scavenging activity towards 1,1-diphenyl-2- picryhydrazyl (DPPH) radical. The results of these methods were compared to those obtained by scavenging of the stable free radicals DPPH and TEMPOL (4-hydroxy-2,2,6,6-tetramethyl-lpiperidinyloxyl), both monitored by EPR spectroscopy. Antioxidant activities were compared to the standard antioxidants, butylated hydroxyluene (BHT) and L-ascorbic acid. Results showed that PCB possesses impressive antioxidant activity in all the tests. The integral intensity of the EPR spectra of both TEMPOL and DPPH was decreased upon PCB addition in a dose-dependent manner. Titration of PCB absorption spectrum with DPPH and TEMPOL revealed metachromatic effects. Biochemical significance and commercial importance of our findings will be briefly discussed.

36 P 6. Influence of different extraction procedures on the antiradical activity and phenolic profile of Rosa rugosa petals Marta Olech, Renata Nowak Department of Pharmaceutical Botany, Medical University of Lublin, 1 Chodźki Street, Lublin, Poland Rugosa rose (Rosa rugosa Thunb.) is an Asian indigenous plant with a long record of traditional medicinal use. Once introduced to Europe, hips and flowers of rugosa rose as well as its hybrids have been widely available and used for production of teas, wines, juices, or jams (1). Antioxidants belong to the one of the most desirable plant components and their application for food purposes is becoming increasingly popular. Our previous research (2) as well as reports of other researchers have revealed the high antiradical activity of R. rugosa petals (3). Recent studies on exploiting natural compounds have drawn much attention to the effective extraction of the desired active ingredients from natural products. Therefore having knowledge about activity of rugosa rose petals, it appears worthwhile to investigate which extraction method should be used in order to bring out the maximum amount of antiradical substances from the plant. That is why our study was designed to determine the influence of different extraction procedures on the antiradical activity and phenolic profile of Rosa rugosa petals. Since antiradical activity is particularly related to the presence of phenolics it was decided to examine an impact of polar solvents on the activity of the extracts and extraction capacity of phenolic antioxidants. The effect of temperature and extraction type was studied as well. For this purpose twenty extracts prepared from petals by the use of classical extraction methods and accelerated solvent extraction were examined. It was demonstrated that the extent of the antioxidant activity depends on the presence of phenolics. The correlation between IC 50 and total phenolic content was found to be extremely high in teas, which was in accordance with the results reported in previous studies (4). In order to achieve extracts from rugosa rose petals with the highest activity and phenolic content the use of mixture of polar organic solvents with water is recommend. Selection of method (traditional or ASE) is less important. However, the extraction temperature when using aforementioned mixtures should not exceed 100ºC, since large amounts of ballast compounds are then extracted. References 1. Hashidoko Y.: The phytochemistry of Rosa rugosa. Phytochemistry, 43, , Olech M., Nowak R., Los R., Rzymowska J., Malm A., Chrusciel K.: unpublished data 3. Ng T.B., He J.S., Niu M., Zhao L., Pi Z.F., Shao W., Liu F.: A gallic acid derivative and polysaccharides with antioxidative activity from rose (Rosa rugosa) flowers. J. Pharm. Pharmacol. 56, , Samaniego-Sánchez C., Inurreta-Salinas Y., Quesada-Granados J.J., Blanca-Herrera R., Villalón-Mir M., López-García de la Serrana H., et al.: The influence of domestic culinary processes on the Trolox Equivalent Antioxidant Capacity of green tea infusions. J. Food Comp. Anal., 24, 79 86, 2011.

37 P 7. Vapour phase antimicrobial activity of selected essential oils against food borne bacteria and toxigenic fungi Alina A. Dobre 1, Irina Smeu 1, Valeria Gagiu 1, Petru Niculita 2 1 National Institute of Research & Development for Food Bioresources IBA, 6 Dinu Vintila Street, RO , Bucharest, Romania, Tel/Fax: ; 2 University of Agricultural Sciences and Veterinary Medicine, Biotechnology Faculty, 59 Marasti Blv, Bucharest, Romania Among promising alternative methods to control food spoilage much attention is being paid to the use of essential oils (EOs). EOs and their components from medicinal and aromatic plants, are gaining increasing interest because of their relatively safe status, their wide acceptance by consumers, their safe for environment and low risk for pathogens to develop resistance to chemical components mixing, due to the diversity of mechanisms of action. The aim of this research was to identify the antimicrobial properties of seven EOs in vapour phase. In vitro antimicrobial activity against four different bacterial and five fungal strains that are involved in food poisoning and/or food decay (Staphylococcus aureus, Bacillus cereus, Escherichia coli, Salmonella enteritidis, Fusarium graminearum, Fusarium culmorum, Aspergillus flavus, Aspergillus oryzae and Aspergillus brasiliensis) was evaluated by disc volatilization method. This method evaluates the activity of EOs volatile vapours on microorganisms, technically near to disc diffusion method. The majority of the selected EOs presented inhibitory activity against all the microorganisms tested but EOs of oregano and white thyme proved the best antibacterial and antifungal activity. Oregano oil and white thyme oil inhibited both gram-positive and gramnegative bacteria and were the most active EOs in vapour phase giving large inhibition zones. The rest of the EOs showed minor or no inhibition to the bacterial strains. Results demonstrated that volatile vapours of majority of EOs had inhibitory activity against the germination of spores and mycelia growth of test fungi. According to volatilization method white thyme, clove bud, oregano and cinnamon leaf were found to be the oils with the widest spectrum of activity against all fungal strains tested but Aspergillus spp. were most susceptible to these EOs especially to white thyme oil. The biological activity of these EOs would be expected to correlate with respective chemical composition, the structural configuration of the constituent component, their functional groups and possible synergistic interactions between components. Disc volatilization method proved to be a useful method for simple screening of antimicrobial activity of volatile vapours of EOs. In conclusion, oregano and white thyme EOs are highly effective in vapour phase and could be used for further investigation in active packaging of food in order to extend the shelf life and increase the safety of the processed food. Keywords: essential oils, foodborne bacteria, toxigenic fungi, vapour phase antimicrobial effect

38 P 8. The influence of alcohol concentration on the phenolic composition and antioxidant capacity of Tunisian myrtle (Myrtus communis L.) extracts Ahmed Snoussi 1, Slim Zgoulli 2, Mohamed Moncef Chaabouni 1, Philipe Thonart 2, Nabiha Bouzouita 1 1 High School of Food Industries, 58, Avenue Alain Savary, 1003 Tunis, Tunisia 2 Centre Wallon de Biologie Industrielle, Boulevard de Rectorat, 27, Bât. B22 Sart Timan 4000 Liège, Belgium. Myrtle (Myrtus communis L.) is an evergreen shrub which grows spontaneously in the Mediterranean area and appreciated for its aromatic and pharmacological properties. In the last years, myrtle importance has recently grown in association with the increasing success of the liqueur produced by its fruits and leaves. In Italy, liqueur production accounts for more than three million liters per year and its success is still increasing. The aim of this work was to investigate the influence of alcohol concentration on the phenolic composition and antioxidant capacity of extracts used for the preparation of myrtle liqueur. Different extract were obtained using alcohol-water mixtures as extraction medium in the range % (v/v). Flavonoïds and anthocyanins were identified by HPLC coupled with Electrospray Mass Spectrometry and quantified during the maceration period by HPLC coupled with Ultraviolet/Visible Detection. Antioxidant activity was tested by the DPPH radical assay. Dry matter, ph, colour parameters (L, a, b) were also analyzed during the maceration. The used solvents gave extracts with similar relative characteristics. Nevertheless, the extract obtained with 80% ethanol showed the highest total antioxidant activity (87.5%). These results suggest that the use of ethanol 80% provides the extract with the best characteristics for liqueur preparation. This study contributes to significantly increase the marketing appeal of myrtle fruits. Keywords: Myrtus communis L., fruits, alcoholic extracts, extraction medium, phenolic composition, antioxidant capacity.

39 P 9. MASS TRANSFER KINETICS DURING OSMOTIC DEHYDRATION OF APRICOT IN SUGAR BEET MOLASSES Marija Petrović, Tanja Brdarić, Katarina Antić, Marija Babić, Vesna Pavelkić Institute "Kirilo Savić", Vojvode Stepe 51, Belgrade, Serbia Osmotic dehydration is a process of partial removal of water by submersing fruits in hypertonic solution. The present work aimed to study kinetics of osmotic dehydration apricot slices in terms of solid gain and water loss. Sugar beet molasses (solid content 80, 60 and 40%) with NaCl (5%w/w) was used as an osmotic medium. One temperature level of osmotic solution ( 55 ºC) for 300 min was evaluated. The weight ratio of solution to sample during the experiment was 4:1. Experimental results were fitted in the Peleg s empirical model of osmotic drying kinetics which expresses the influence of analyzed experiment factors on water loss (WL). Mass transfer coefficients of water, Peleg rate constant (k 1 ) and Peleg capacity constant (k 2 ), were also estimated. Water loss increased with the increase of solution solid content which is presumably due to the greater osmotic pressure gradient. Peleg s equation parameters for water loss varied from 0.06 hg -1 to 0.14 hg -1 for k 1 and 0.29 g -1 to 0.40 g -1 for k 2, respectively. Correlation coefficient calculated for the proposed model was high (R= 0.997). It indicates fine agreement between experimental and model values for water loss. Keywords: osmotic dehydration, mass transfer, apricot.

40 P 10. HPLC DAD analysis, antimicrobial activity and Cytochrome P450 enzymes inhibition of Salicornia herbacea methanolic extract ESSAIDI Ismahen 1, BRAHMI Zeineb 2, CASABIANCA Hervé 3, CHAABOUNI M ed Moncef 1 and BOUZOUITA Nabiha 1 1 Ecole Supérieure des Industries Alimentaires, 58 Avenue Alain Savary, 1003 Tunis, Tunisie. 2 Department of Nutritional Faculty of Applied Bio-Science Tokyo University of Agriculture Sakuragaoka 1-1-1, Setagaya-ku, Tokyo. ZIP: Centre National de la Recherche Scientifique, Service Central d analyse, Echangeur de Solaize- Chemin du Canal, Solaize, France. In this study methanolic extract of Salicornia herbacea a food plant consumed in coastal zones was analyzed using HPLC-DAD, five compounds were detected (Uracil, ferulic acid, cafeic acid, p-coumaric acid and quercitin). P-coumaric acid has the important content with 4.24µg.mg -1. Biological activities of Salicornia extract were conducted on the study of antibacterial and the cytochrome enzymes inbition activities. The antimicrobial activity of was tested against six microorganisms (Eshirichia coli, Pseudomonas aeruginosa, Salmonella enteritidis, klebsiella pneumoniae Staphylococcus aureus and Streptococcus A) using inhibition zone method. The Gram + bacteria were more sensible than Gram -. Saphylococcus aureus was the most inhibited strain its inhibition zone was 17mm and Eshirichia coli was the most resistant with only 9mm of inhibition zone. The Cytochrome P450 enzymes inhibition activity of Salicornia extract was tested using three types (CYP3A4, CYP1A2 and CYP2D6). The IC 50 values were ± 0.40, 3.88 ± and 4.66 ± µg.ml -1 respectively for CYP1A2, CYP2D6 and CYP3A4. Keywords: Salicornia herbacea, HPLC-DAD, phenolic compounds, antimicrobial activity, CYP inhibition activity.

41 P 11. SHELF-LIFE PROLONGING OF FRESH-CUT ROMANIAN LETTUCE Irina Smeu 1*, Mona-Elena Popa 2, Alina Dobre 1, Mariana Ionescu 1, Nastasia Belc 1, Giuseppe Spadaro 1, Gabriel Mustatea 1 1 National Institute of Research & Development for Food Bioresources IBA Bucharest, 6 Dinu Vintila Street, Bucharest, Romania 2 University of Agricultural Sciences and Veterinary Medicine, Biotechnology Faculty, 59 Marasti Blv, Bucharest, Romania * Corresponding author: smeu_irina@yahoo.com; Development and assessment of an alternative packaging system was studied on Romanian Gra ia lettuce (Latuca sativa L. var. Gra ia), under different treatments. To highlight the effect of minimally processed vegetables, samples were submitted to different treatments: fresh-cut lettuce washed with tap water and with 100 mg/l chlorinated water. The samples were stored under refrigeration controlled conditions, approx. 4 C and high relative humidity for 3 days. Unwashed lettuce was used as control sample. Changes in respiration rate, sensory quality, water loss, physicochemical and microbiological parameters were daily evaluated. Fresh-cut lettuce was packed in normal atmosphere, using different types of packaging materials: nanocomposite-based LDPE/modified silicate monolayer films containing starch and hydrolyzed collagen and common PP films. The sealed bags were stored at 4 C for 10 days. The permeability properties to O 2, CO 2 and water vapor were correlated with the microbiological and sensory analysis. In order to develop an additional packaging method and to prolong the shelf-life of the selected product, the research activity also included in vitro tests on isolated microorganisms from the natural microbiota of lettuce. Three volatile essential oils (EOs) were tested: oregano oil (Thymus capitatus), basil oil (Ocimum basilicum) and white thyme oil (Thymus vulgaris). Good results, in terms of an increased shelf-life were obtained for washed salads using chlorinated water and packed in LDPE/silica-Amp bags, for which can be estimated a shelf-life up to 7 day, stored under refrigeration conditions, compared to 3 days for the unpacked control samples. Regarding experiments involving the EOs, oregano oil presented the highest inhibitory activity against the tested microorganisms, therefore it will be used in further experiments, along with modified atmosphere packaging (MAP) techniques to extend the shelf-life of minimally processed Romanian lettuce. Keywords: shelf-life; minimally processed vegetables; lettuce

42 P 12. Purification of β-glucosidase from sweet almond (Prunus dulcis var. amygdalus) Anja Gavrilović 1, Nataša Božić 2, Nikola Lončar 1, Marica Grujić 1 and Zoran Vujčić 1* 1 Faculty of Chemistry, University of Belgrade, Studentski trg 12-16, Belgrade, Serbia 2 Institute of Chemistry, Technology and Metallurgy-Center of Chemistry, University of Belgrade, Studentski trg 12-16, Belgrade, Serbia * zvujcic@chem.bg.ac.rs β-glucosidase (EC ) catalyzes the hydrolysis of terminal, non-reducing β-dglucose residues with release of β-d-glucose and has wide specificity for β-d-glucosides. Because of its specificity enzyme has found a lot of applications in food industry, especially in winemaking and juice processing, where it is used for the hydrolysis of anthocyanins and terpenoglucosides thus contributing to aroma formation. Also it is used in cosmetic and pharmaceutical industry for obtaining non-ionic biodegradable surfactants. Existence of four isoforms of β-glucosidase in the extract of sweet almond has been reported. Among them isoenzyme A, which is a glycoprotein and dimer of 130 kda, is the most abundant and the most active one. Usual purification procedures described in literature imply fractional ammonium sulphate precipitation and several chromatographic techniques that result in partly purified enzyme preparation with no isoenzyme homogeneity. Nowdays production of enzymes at industrial level require elimination of ammonium sulphate step in a protein purification because of the high costs of waste disposal produced in the process and environmental pollution caused by the ammonium ion. Having all of this in mind, the object of our work was to purify β-glucosidase isoform A to homogeneity without using ammonium sulphate precipitation step. After the grounding, almond was defatted whit acetone. Defatted flour was extracted whit 50 mm acetate buffer ph 5.7 and the enzyme was purified using combination of several chromatographic techniques; ion exchange chromatography on QAE Sephadex A-50, ion exchange chromatography on Q Sepharose followed by gel chromatography on Superose 12 and ion exchange chromatography on Q Sepharose. The hydrolytic activity of β-glucosidase was determined in reaction with p- nitrophenyl-β-d-glucopyranoside (pnpg) spectrophotometrically at 405 nm, by measuring the release of p-nitrophenol. Fractions containing enzyme activity were analysed by SDS-polyacrylamide gel electrophoresis (SDS PAGE) and isoelectric focusing followed by zymogram detection using esculin and pnpg as a substrates. After purification, isoform A of β-glucosidase with molecular mass of 62 kda has been purified to homogeneity by 35-fold. Avoiding of ammonium sulphate precipitation had no negative influence on enzyme purity. Lower costs, lesser environmental pollution and easier purification procedure open up a possibility of improving enzyme characteristics by means of chemical modification and immobilisation thus enabling its broader application in food industry.

43 P 13. Impact of fatty acids binding to human serum albumin on the reaction of free thiol group of albumin I.D. Pavićević, V.J. Jovanović, J.M. Aćimović, LJ.M. Mandić Faculty of Chemistry, Department of Biochemistry, University of Belgrade, P.O. Box 51, , Belgrade, Serbia Supplementation of omega-3 fatty acids reduces the risk of heart attack and coronary heart disease, and helps in hypertriglyceridemia. In etiology of these diseases oxidative stress is implicated. Human serum albumin (HSA) is the most important transporter of free fatty acids in circulation. Also, it contains one free thiol group (Cys34, noted as hydroxyl radical scavenger), which determine antioxidant property and carbonyl scavenger capacity of albumin. Crystallographic studies showed that accessibility of HAS Cys34 residue to oxidation was significantly changed when free fatty acids were attached to HSA. Therefore, the aim of this study was investigation of the impact of unsaturated fatty acids binding to HSA on the reaction of HSA- free thiol group with methylglyoxal. The incubation of HSA (0.5 mm) with MG(41 mm) in 0.1 M sodium phosphate buffer (ph 7.4) at 370C was performed without and with unsaturated fatty acids (oleic acid, EPA and DHA) and fish oil during the six hours. The percent contents of the most abundant omega-3 fatty acids in fish oil (eicosapentaenoic acid, 20:5, Δ5,8,11,14,17, and docosahexaenoic acid, 22:6, Δ4,7,10,13,16,19) were analyzed with GC-FID. Free thiol groups were assayed spectrophotometrically according to the modified Ellman s method (with 5,5'-dithiobis-(2- nitrobenzoic acid as reagent)). Changes in the reactivity of free HSA thiol group with methylglyoxal in the function of unsaturation of the fatty acid attached to HSA were observed. The percent of reacted thiol group of HSA incubated with MG in the absence or presence of oleic acid, increased from 21% to 33%. Further increasing of reactivity of HSA thiol group was detected when HSA was incubated with more unsaturated fatty acids, EPA and DHA. These results showed that reactivity, i.e. accesibility of thiol group of Cys34 residue to carbonylation increased with increasing unsaturation of fatty acids attached to albumin. Keywords: HSA thiol group reaction with methylglyoxal; HSA-fatty acids binding, fish oil dietary supplement

44 P 14. EVALUATION OF NITRATES CONTENT OF SOME VEGETABLE SPECIES CULTIVATED IN OPEN FIELD, USING AN ENZYMATIC METHOD Alina Cristina Bălea 1, Monica Catană 1, Luminiţa Catană 1, Mioara Negoiţă 1, Enuţa Iorga 1, Floarea Burnichi 2 1 National Institute of Research and Development for Food Bioresources IBA Bucharest, 6 th Dinu Vintila Street, 2 nd District, RO Bucharest, Romania, tel.: , fax: , balea_alinaa@yahoo.com 2 Vegetable Research and Development Plant for Horticulture Buzău, 23 Mesteacãnului Street, Buzãu Nitrites and nitrates are natural components of the soil from nitrogen mineralization of organic substances of plant and animal origin. Nitrogen mineralization takes place primarily through existing microorganisms in soil. In areas with temperate climate, this process is carried out with maximum intensity in hot season. In this paper are presented results that establish the influence of fertilization treatments on nitrates content of some vegetable species, cultivated in the field: cabbage, carrots, bell peppers and onion. In the culture technology of these vegetables, were applied the following fertilization variants (fertilizer being ammonium nitrate with 33% nitrogen): V1 = 0 kg nitrogen/ha; V2 = 100 kg nitrogen/ha; V3 = 200 kg nitrogen/ha; V4 = 400 kg nitrogen/ha; V5 = 800 kg nitrogen/ha. An enzymatic method was used for determination of nitrates content of vegetables cultivated in the field. In this method, nitrate is reduced by the reduced form of nicotinamide adenine dinucleotide phosphate (NADPH), to nitrite, in presence of nitrate-reductase. Amount of oxidized NADPH is stoechiometrically equal with nitrate amount. Decreasing of NADPH amount is measured through absorbance at ג = 340 nm. The vegetable species obtained in field culture, through application of five fertilization variants, have a potential of nitrates accumulation in the range, as follows: mg NO 3 - /kg mg NO 3 - /kg (for cabbage samples), mg NO 3 - /kg mg NO 3 - /kg (carrot samples), mg NO 3 - /kg mg NO 3 - /kg (bell pepper samples), mg NO 3 - /kg mg NO 3 - /kg (onion samples). Keywords: Nitrites, vegetable species, enzymatic method References: 1. Bibicu, M., Research methodology for the determination of nitrates and nitrites in plant tissues and the level of accumulation in horticultural products, Luchian, V., General and special cultivation of vegetables, Elisavaros Ed., Working protocol for enzymatic method, R Biopharm, 2008

45 P 15. Chemical Analysis, Antimicrobial and Antioxidant Activities of Spirulina (Arthrospira) Powder Fractions G.T. Sotiroudis 1,2, I. Pontikos 1, M. Anastasiadis 1, I. Chinou 2, A. Xenakis 1 and T.G. Sotiroudis 1 1 Institute of Biological Research and Biotechnology, National Hellenic Research Foundation, Athens, Greece 2 Laboratory of Pharmacognosy, Department of Pharmacy, University of Athens, Greece Spirulina (Arthrospira), is a microscopic and filamentous cyanobacterium that has a long history of use as a safe food lacking toxicity. Recent experimental evidence suggests potential health benefits of Spirulina which involve bioactive lipid components including γ-linolenic acid (GLA), tocopherols, β- carotene, glycolipids and phycocyanobilin. Spirulina sp. was commercially produced by ALGAE A.C. (Nigrita, Greece) by cultivation in greenhouse production ponds using fresh water heated by geothermal fluids. Drying of the fresh algal slurry was performed in a greenhouse by laying the product on plastic tables and heating by circulation of geothermal water in the drying area. The dried biomass was further milled and the algal powder was stored at room temperature under dry conditions. Since various drying methods affect differently the quality of Spirulina bioactive components, we studied the effect of the above commercial drying procedure on several Spirulina lipid constituents and their antimicrobial and antioxidant properties. We first examined the volatile components of Spirulina dry biomass (isolated by hydrodistillation using a modified Clevenger-type apparatus or extraction with n- pentane), which were analyzed by gas chromatography and mass spectrometric (GC-MS) detection. Twelve components were identified. The major components from these samples were heptadecane (77.88%) and 6,10,14-trimethyl-2-pentadecanone (6.09%) for the essential oil and L-linalool (10.5%), 9(Z)-octadecenoic acid (10.19%), hexadecanoic acid (5.0%) and cis-linalool oxide (4.08%) for the pentane extract. Additionally, several constituents from the dichloromethane extract have been isolated by Si gel chromatography and identified by GC-MS. Major components included hexadecenoic acid and 1,1 -bicyclohexyl. This is the first time that the cycloalkane bicyclohexane was identified as a constituent of microalgae. Moreover, the antimicrobial activity of methanol-, cyclohexane- and dichloromethaneextracts was also assayed against six human pathogenic bacteria and three fungi through both the disc diffusion as well as the dilution methods. The methanolic extract appeared as the most active, showing also a wide antimicrobial profile against all the tested microorganisms, while the pure bicyclohexane showed comparable activity. Furthermore, Spirulina methanol powder extracts showed significant polyphenol contents and 2,2-diphenyl-1-picrylhydrazyl (DPPH) stable free radical scavenging activities, when compared to those of 4-methylcatechol and butylated hydroxytoluene (BHT) standard antioxidants. Sunflower oil extracts of Spirulina are efficiently protected against thermal oxidation (110 o C), as measured by their increase of absorbance at 232 nm, when compared to the heated native vegetable oil, which is not enriched in lipophilic antioxidant components of Spirulina powder. It can be suggested that Spirulina antioxidants can be used in stabilizing the complex frying system of vegetable frying oils. This work was supported by a GSRT Greece-Spain Joint Research and Technology Programme (006-γ).

46 P 16. Selective Analysis of Thiram by LC/MS and LC/MS-MS B. Daniela Ringli 1, Wolfgang Schwack 1 1 Institute of Food Chemistry, University of Hohenheim, Garbenstrasse 28, Stuttgart, Germany; Wolfgang.Schwack@uni-hohenheim.de Dithiocarbamates (DTCs) are widely used fungicides in agriculture. They are in use since many decades, and still adequate analytical methods for the determination of DTCs in foodstuffs are not available. Generally, DTCs in foodstuffs are analyzed by hot acid hydrolysis and determination of CS 2 as a sum parameter by UV spectrophotometry or gas chromatography, e.g. [1]. CS 2 is a decomposition product formed by all DTCs so that it is not possible to destinguish between the different active compounds. The different toxicity, as well as the different allowed fields of application, and, the specified maximum residue limits (MRLs) stated by the European Commission for propineb, thiram and ziram [2] require specific methods for DTC analysis. Many methods for the determination of a single compound are available, but in the time of multi residue analysis these methods are not sufficient for routine food control. The nature of DTCs makes them difficult to access by analysis. Most compounds are practically insoluble in water or organic solvents and rapidly degenerate when coming into contact with air humidity and especially acidic plant juices. Crnogorac et al. presented methods for the simultaneous determination of the three DTC sub classes dimethyldithiocarbamate (DMD), ethylenebis(dithiocarbamate) (EBD) and propylenebis (dithiocarbamate) (PBD) by LC/MS [3] and LC/MS-MS [4]. In the present work, thiram was integrated into the methods of Crnogorac et al. by using another buffer for the surface extraction of thiram. Under the alkaline conditions used before, thiram rapidly decomposes completely yielding DMD and, therefore, leading to false positive DMD findings. An additional extraction with dilute sulfurous acid was introduced, by which thiram is quantitatively transformed into a stable DMD sulfite adduct clearly marking the presence of that fungicide. The determination was studied by both LC/MS and LC/MS-MS, using d 12 -thiram (High Purity Compounds) as internal standard. Chromatography was performed on a ZIC-pHILIC column (Merck SeQuant) using an acetonitrile/10 mm aqueous ammonia gradient. Recovery experiments with spiked apples, tomatoes, white grapes, peaches and nectarines showed both high recoveries and low limits of quantification. This method allows the extraction and selective determination of thiram residues among other DMD like ziram. References [1] BVL. Amtliche Sammlung von Untersuchungsverfahren nach 64 Lebensmittel- und Futtermittelgesetzbuch. L , Beuth-Verlag, Berlin (1998) [2] European Community. Commission Directive 2006/125/EC. Official Journal of the European Union; 50: 16 (2007) [3] Crnogorac G., Schwack W., Determination of dithiocarbamate fungicide residues by liquid chromatography/mass spectrometry and stable isotope dilution assay. Rapid Commun. Mass Spectrom.; 21: 4009 (2007) [4] Crnogorac G., Schwack W., Schmauder, S., Trace analysis of dithiocarbamate fungicide residues on fruits and vegetables by hydrophilic interaction liquid chromatography/tandem mass spectrometry. Rapid Commun. Mass Spectrom.; 22: 2539 (2008)

47 P 17. Antioxidant activity and phenolic contents of some Polish wild mushroom extracts Marta Drozd, Renata Nowak Department of Pharmaceutical Botany, Medical University of Lublin, Chodźki 1 Str., Lublin, Poland; tel. (81) Wild mushrooms have been commonly used worldwide for culinary (flavouring) purposes and recently they have been recognized as a nutritious food. Mushrooms have been reported to have hypotensive, anticholesterolemic, hypoglycemic, anti-inflammatory, antibacterial, antiviral, and antifungal properties. Furthermore, their role in prevention and treatment of various cancers (breast, stomach, liver, colorectal, lung, cervical or endometrium) has been of much interest. The pharmacological properties of mushrooms are strictly associated with the presence of such chemical compounds as phenolics, terpenes, steroids, polysaccharides and proteins. Mushroom phenolic compounds have been found to be an excellent antioxidant, capable of scavenging free radicals, which are responsible for the oxidative damage of lipids, proteins, and nucleic acids. Therefore, in this study, the antioxidant activities of seventy six wild mushrooms, coming from Włodawa region of east Poland, were investigated in relationship to their total phenolic contents. The antioxidant activity of the ethanol extracts was investigated according to the DPPH method. Vitamin C, gallic acid and Trolox were used as positive control. The scavenging activity of mushroom extracts towards DPPH free radicals was expressed in terms of IC 50. The amount of total phenolic contents in the mushroom extracts was determined calorimetrically according to Polish Pharmacopoeia VII method with the Folin-Ciocalteu (FC) reagent, using some modifications. All data were expressed as means ± standard deviation of (3n) measurements. Correlation between the antioxidant activity and total phenolic contents was carried out using the correlation and regression in the Excel program. Ganoderma applenatum extract showed a high antioxidant activity, being able to scavenge 50% of the radicals at concentration of µg/ml. Lycogala sp. extract showed the lowest activity values of all the analyzed fruiting bodies. Phenols concentration in selected mushroom extracts ranged from almost mg/g such as in Ganoderma applenatum to 1.53 mg/g in Cantharellus cibarius. Positive correlations were found between total phenolic content in the mushroom extracts and their antioxidant activities. Though other antioxidants were probably present in these mushroom extracts, phenolic compounds could make a significant contribution to the antioxidant activity in these extracts. Having established the antioxidant activity in these mushroom extracts, the chemical characteristics of the antioxidant components in these extracts will be further investigated. Edible mushrooms may have potential as natural antioxidants.

48 P 18. The mechanism of the cytotoxic and antiproliferative effects of polyphenolic green tea, coffee and cocoa extracts Maja Krstic, Marija Stojadinovic, Jelena Radosavljevic, Luka Mihajlovic, Dragana Stanic-Vucinic, Tanja Cirkovic Velickovic Faculty of Chemistry, University of Belgrade, Studentski trg 16, Belgrade, Serbia Coffee, green tea and cocoa are popular bavarages rich in antioxidants, especially phenolic acids and derivatives of catechins, known for their health promoting properties. In accordance with previous experimental datas the aim of this paper is to identify and explain the biological effects of cocoa, coffee and green tea extracts on tumor cell line of cervical cancer, HeLa cells and the role of oxidative stress and free reactive oxygen species in induction of apoptosis and necrosis of HeLa cells treated with different polyphenolic extracts. Total phenolics of extracts were determined by Folin-Ciocalteu s method. Cytotoxic activity in human cervical carcinoma cell lines (HeLa) was assayed by viability testing using MTT. Intracellular reactive oxygen species (ROS) were determined by flow cytometry following incubation of cells with phenolic extracts and ROS reactive fluorescent probe 2,7- dichlorofluorescin diacetate. The intracellular GSH levels were evaluated using CMF-DA. To measure mitochondrial membrane potential the fluorescent probes DiOC6 were used. The cell cycle and DNA damage were evaluated with PI staining and flow cytometry. All tested extracts exhibited cytotoxic activity in HeLa cell lines. Green tea had the highest cytotoxic activity with IC 50 of mg of gallic acid equivalents/ml of extract, followed by coffee extract with IC 50 of mg/ml and cocoa extract with IC 50 of 311,669 mg/ml. Treatment of HeLa cells with green tea extract led to increased levels of intracellular H 2 O 2 and superoxide anion radicals, mitochondrial membrane potential decline and cell apoptosis. Cocoa extract had no significant cytotoxic effect and did not induces apoptosis of HeLa cells. Also, no significant production of ROS or MMP-fall were noticed, however, treatment induced cell cycle arrest. The results obtained after treatment of HeLa cells with polyphenolic extract of coffee showed a slight decrease of MMP, increased levels of superoxide anion radicals, but no accumulation of H 2 O 2, probably due to its more efficient removal from cells. However, it is shown a slight increase in levels of reduced GSH and could be assumed that these effects are a consequence of modulation of the enzyme GSH peroxidase and/or GSH reductase, leading to further reduction of H 2 O 2 and reduction of oxidized GSH. Keywords: apoptosis; intracellular reactive oxygen species; the cell cycle; mitochondrial membrane potential; green tea; coffee; cocoa; cytotoxicity; glutathione; glutathione reductase; glutathione peroxidase.

49 P 19. ANTIBACTERIAL ACTIVITY OF SILVER NANOPARTICLES Gabriel Mustatea 1, Ioan Calinescu 2, Alina Dobre 1, Mariana Ionescu 1 1 National Institute of Research and Development for Food Bioresources IBA Bucharest, 6 Dinu Vintila Street, Sector 2, RO Bucharest, Romania, tel.: , fax: , e mail: mustatea_gaby@yahoo.com 2 Politehnica University of Bucharest, Faculty of Applied Chemistry and Science Material, Bucharest, Romania The antibacterial effects of silver ions or salts have been noticed since antiquity 1 ; but the effects of Ag nanoparticles on microorganisms and antimicrobial mechanism have not been revealed clearly. However, it is well known that Ag ions are highly toxic to microorganisms, showing strong biocidal effects on more than 12 species of bacteria 2, 3. Starting from a 0.5 mm AgNO 3 solution, using microwaves, a colloidal solution of silver nanoparticles was obtained. The antibacterial susceptibility of obtained silver nanoparticles was evaluated using the disc diffusion method. The bactericidal effect of the silver nanoparticles was observed using Bacillus cereus, Salmonella enteritidis, Staphylococcus aureus and Escherichia coli as indicator strains. After 24 hours of incubation at 37 Celsius degrees zones of inhibition were measured. References 1. Silver S., Phung LT. Bacterial heavy metal rezistance: new surprises. Annu Rev Microbiol. 1996; 50: Zhao G., Stevens Jr., Multiple parameters for the comprehensive evaluation of the susceptibility of Escherichia coli to the silver ion. Biometals 1998; 11: Prema P., Raju R., Fabrication and characterization of silver nanoparticles and its potential antibacterial activity, Biotech. and Bioproc. Eng. 2009, 14: Keywords: silver nanoparticles, antibacterial activity, diffusion, zone of inhibition

50 P 20. Antioxidative and immunomodulating activities of polysaccharide extracts from the basidiomycetes mushrooms Maja Kozarski 1, Anita Klaus 1, Miomir Niksic 1, Miroslav M. Vrvic 2, Dragica Jakovljevic 3 and Leo L.J.D. van Griensven 4 1 Institute for Food Technology and Biochemistry, Faculty of Agriculture, University of Belgrade, Nemanjina 6, Belgrade 11080, Serbia; 2 Faculty of Chemistry, University of Belgrade, Studentski trg 12-16, Belgrade, Serbia; 3 IChTM - Department of Chemistry, University of Belgrade, Njegoseva 12, Belgrade 11001, Serbia; 4 Plant Research International, Wageningen University and Research Centre, Droevendaalsesteeg 1, Wageningen 6700 AA, The Netherlands Water-soluble polysaccharide-enriched fractions were isolated from the basidiomycetes mushroom species Agaricus bisporus, Agaricus brasiliensis and Phellinus linteus [1,2]. Their antioxidant activities were investigated using in vitro assay systems: 1,1-diphenyl-2- picrylhydrazyl (DPPH) radical scavenging and ferric-reducing antioxidant power assay. Immunomodulation was tested in vitro, by measuring the synthesis of interferon-gamma (IFN-γ) by enzyme linked immunosorbent assay (ELISA). To explain the possible differences observed, we have measured the total polysaccharide, glucan and total phenolic contents of mushrooms extracts. With regard to scavenging ability on DPPH radicals, the P. linteus extract showed very good scavenging ability as evidenced by their particularly low EC 50 values (< 0.1 mg/ml). For A. brasiliensis and A. bisporus, EC 50 values were 0.27 and 2.0 mg/ml, respectively. P. linteus extract with the highest phenol showed the highest scavenging ability. For reducing power of P. linteus, A. brasiliensis and A. bisporus EC 50 values were found of 0.47, 3.13 and mg/ml, respectively. Regression analysis revealed a strong and significant correlation between the following parameters: EC 50 (reducing power) and total phenols (r = , p < 0.05); EC 50 and total polysaccharide content (r = 0.699, p 0.05); total glucan and β-glucan contents (r = 0.966; r = 0.982, p < 0.05). Measurements of the immunomodulatory activity showed that A. bisporus, and A. brasiliensis polysaccharides extracts cause an increased synthesis of IFN-γ in human PBMC s, suggesting proinflammatory effects, while P. linteus extract showed a decrease of IFN-γ synthesis suggesting an immunosuppressive activity. Modified polysaccharides of A. bisporus and A. brasiliensis by 1,6 β-glucanase showed a strong enhancement of immunostimulatory activity compared to the native extracts. P. linteus lost immunosuppressive effect on PBMC's and IFN-γ synthesis. Results confirmed that the primary structure of polysaccharides is of more importance then the tertiary structure for their immunostimulating activity. References [1] Kozarski, M. et al.,(2011), Antioxidative and immunomodulating activities of polysaccharide extracts of the medicinal mushrooms Agaricus bisporus, Agaricus brasiliensis, Ganoderma lucidum and Phelinus linteus. Food Chemistry 129, [2] Klaus, A., et al.,(2011), Antioxidative activities and chemical characterization of polysaccharides extracted from the basidiomycete Schizophyllum commune. LWT-Food Science and Technology 44,

51 P 21. Screening a wild type strains of Bacillus sp. that produce α-amylases in solid state fermentation Marinela Šokarda Slavić 1, Nataša Božić 2* and Zoran Vujčić 1 1 Faculty of Chemistry, University of Belgrade, Studentski trg 12-16, Belgrade, Serbia 2 Institute of Chemistry, Technology and Metallurgy-Center of Chemistry, University of Belgrade, Studentski trg 12-16, Belgrade, Serbia * nbozic@chem.bg.ac.rs Starch is the most important carbon and energy source among plant carbohydrates, and it is the second following cellulose in total biosynthesis. It represents an inexpensive source for production of glucose, fructose and maltose syrups with are widely used in food industries and for obtaining the products of their fermentation such as the bioethanol. α-amylases are extracellular enzymes that randomly cleave the α-1,4 glycosidic bonds of starch molecules. This enzyme is extensively used in starch liquefaction, and the food and sugar industries. α-amylase can be obtained by cultivation of Bacillus sp. on natural substrate using solid state fermentation (SSF). In this work a total of 40 spore-forming and amylase producing Bacillus sp. were isolated from soil samples collected from different regions located in Serbia. All strains were tested for amylase production using starch agar plate method. The most potent strains were further tested by SSF. Wild types isolated from hot spring Bogatić (9B), salt spring Ovča (24A) and arable land in Budrige (12B), showed the highest level of α-amylase production when tested in SSF. Influence of different solid substrates (triticale, wheat and corn using whole and partially grinded grains) on α-amylase production in SSF was examined. Amylase extracts obtained from fermentations were examined by spectrophotometric assay and zymographic detection. Several different isoforms were detected in each strain depending on the substrate used. The highest enzymatic activity occurred when cultivating strains on triticale.

52 P 22. Investigation on the adulteration of roasted-grinded coffee using electronic nose system Elena M. Pruteanu, Marta Zachia National Institute of Research and Development for Food Bioresources IBA Bucharest, 6 th Dinu Vintila Street, 2 nd District, RO Bucharest, Romania, tel.: , fax: , pruteanu_elena_marilena@yahoo.com The coffee is sold mainly after roasting and grinding. Materials likely to be mixed with coffee are, generally, roasted chicory, roasted cereals, roasted soy or peas. From this point of view the adulteration of roasted and grinded coffee has been investigated using different methods like microscopical examination or chemical analysis based on compositional differences of the coffee substitutes that involve the determination of the extractives of the dry sample, total nitrogen, crude fiber, caffeine, ether extract, detection of inulin from chicory. We applied a new and modern technique, electronic nose (E-nose) technique, with good results in roasted-grinded coffee adulteration. The testing of the system (FOX 4000) was carried out using seven different types of roasted-grinded coffee, one type of roasted-grinded chickpeas and peas, frequently used in coffee adulteration and roasted chicory, where it was proved successful in classifying and discriminating the tested products. The resulting E-nose intensities were analyzed by Principal Component Analysis (PCA), Discriminant Factor Analysis (DFA), Statistical Quality Control (SQC) etc. Classification rates were above 90%. Keywords: E-nose, coffee, peas, chicory References: 1. Pardo, M. & Sberveglieri, G., Coffee analysis with an electronic nose, IEEE Transactions on Instrumentation and Measurement, 2002, 51(6): Shilbayeh, N.F. & Iskandarani, M.Z., Quality control of coffee using an electronic nose system, American Journal of Applied Sciences, 2004, 1(2):

53 P 23. Total phenolic content and antioxidant properties of different berries harvested in Serbia D. Dabić 1, M. Natić 2, A. Pavlović 2, Ž. Tešić 2 1 Innovation Centre, Faculty of Chemistry Ltd, Studentski trg 12-16, Belgrade, Serbia 2 Faculty of Chemistry, University of Belgrade, P. O. Box 51, Belgrade, Serbia ddabic@chem.bg.ac.rs Berry fruits are rich in polyphenolic compounds such as phenolic acids, flavonoids, and anthocyanins. The phenolic compounds in berries have been reported to have antioxidant, anticancer, antiinflammatory, and antineurodegenerative biological properties. As the strong correlation exists between the composition of phenolic compounds and the bioactivity of berries, accurate quantification of these compounds is considered as very important task. Therefore, the objective of this study was to investigate the total phenolic content and to determine free and total ellagic acid in various berries harvested in Serbia. Total phenolic content was determined by using the Folin Ciocalteu UV-vis spectrophotometric method and expressed as gallic acid equivalents in milligrams per 100 g of fresh weight. Amount of free ellagic acid was determined in methanol and acetone extracts. Total ellagic acid concentration was determined after acid hydrolysis with 4 M HCl in both extracts, and results were compared. Quantification was done using HPLC based on an isocratic elution. Total phenolic, free and total ellagic acid contents varied greatly among cultivars of investigated berries (raspberries, strawberry and mulberry) and among cultivars.

54 P 24. Investigation of antibacterial and antioxidant activities of betalains extract from red beetroot BEN HAJ KOUBAIER Hayet, CHAABOUNI Mohamed Moncef, BOUZOUITA Nabiha High School of Food Industries, 58, Avenue Alain Savary, 1003 Tunis, Tunisia Betalains, the red-violet betacyanins and the yellow betaxanthins, are a class of watersoluble nitrogenous pigments. Interest in this pigment has grown since their biological activities were demonstrated. They are widely used as additives in foods, drugs and cosmetic products because of their natural and non-toxic colorant properties. Red beetroot (Beta vulgaris L.) is one of the major sources of these colorants. In this work, betalains were extracted from red beetroot by aqueous maceration and investigated for antioxidant and antimicrobial activities in vitro. The betalains content of the extract, determined spectrophotometrically, was about 52.62±4.1 mg eq betanin and 45.69±2.73 mg eq vulgaxantin I/g. The betalains compounds were analyzed using HPLC-UV and identified by HPLC-ESI-MS. Antioxidant activity was evaluated for its radical scavenging capacity by 2,2-diphenyl-1- picryldydrazyl (DPPH) radical-scavenging test. Red beetroot colorant exhibited an inhibition concentration (IC 50 ) about 5.00±1.05µg/ml and inhibition percentage (IP) of 97.17±1.41% at the concentration of 200μg/ml. The results indicated that betalains had a very potent antioxidant activity, compared with BHT (IC 50 =19.00±0.98μg/ml) used as a positive control in parallel experiment. The antibacterial activity of betalains extract was tested against six bacteria (E. coli, P. aeruginosa, K. pneumonia, S. enteritidis, S. aureus and Streptococcus A) using the agar disc diffusion method. The obtained results showed that betalains extract has an antibacterial activity against gram positive bacteria as well as gram negative bacteria. Streptococcus A was the greatest inhibited of all the strains tested. Keywords: betalains; red beetroot; antioxidant activity; antibacterial activity

55 P 25. SEMI-PREPARATIVE PURIFICATION AND QUANTIFICATION OF EPIGALLOCATECHIN-3-GALLATE FROM TEAS, COFFEE AND COCOA Vesić J., Mihajlović L., Stanić-Vučinić D., Ćirković Veličković T. Faculty of Chemistry, University of Belgrade, Belgrade, Serbia Black and green teas, coffee and cocoa are the most consumed non-alcoholic drinks worldwide. Epigallocatechin-3-gallate (EGCG) is the most aboundant catechin in tea and has antioxidant, anti-inflammatory and immunosuppressive effects that may have therapeutic applications in the treatment of many disorders. A method was devised for obtaining high quantities of EGCG from natural sources in a way that is fast, simple and cheap. Isolation from natural sources allows us to obtain large quantities of this compound. Reverse-phase high-performance liquid chromatography was used to separate and purify EGCG in green tea food supplements, green tea leaves, black tea, coffee and cocoa. The method uses a ZORBAX Eclipse XDB-C18 semi-preparative column (Agilent Technologies, UK) and a linear gradient of methanol. The method allows for isolation of pure (>90%) EGCG. Quantification was done by LTQ Orbitrap XL hybrid FTMS (Thermo Fisher Scientific, USA). Obtained quantites of EGCG were (4,3 ± 0,1) μg/ml from the green tea food supplement, (0,873 ± 0,004) μg/ml from green tea leaves, (0,58 ± 0,02) μg/ml from black tea and (0,038 ± 0,001) μg/ml from coffee, which corresponds to 42%, 40%, 0,4% and 0,05% of total phenolics respectively. The amount of EGCG obtained from cocoa was under the limit of detection. Modifications of the method show promise in preparation of high quantities (milligrams) of individual catechins suitable for studying their biological effects.

56 P 26. The immobilization of β-galactosidase on chemically modified immobilization supports Milica Carević, Marija Stojanović, Mladen Mihailović, Andrea Stefanović, Sanja Grbavčić, Zorica Knežević-Jugović, Dejan Bezbradica Department of Biochemical Engineering and Biotechnology, Faculty of Technology and Metallurgy, Karnegijeva 4, Belgrade. β-galactosidase is an important industrial enzyme used for the hydrolysis of milk and whey lactose, causing both, health and enviromental benefits. In this paper, different commercial supports were chemically modified in order to improve immobilization of β-galactosidase. Before evaluation of different immobilization methods basic characterization (optimum temperature and ph) of comercial β-galactosidase from Aspergillus orizae was performed. β-galactosidase was covalently immobilized onto different supports in order to compare them in terms of the immobilization yield, type of immobilization and thermal stability. In the first phase of our experimental work, β-galactosidase was immobilized onto unmodified and modified comercial Eupergit C250L supports. Covalent immobilization onto unmodified comercial Eupergit C250L support (made by copolymerization of N,N_-methylenebis-(methacrylamide), glycidyl methacrylate, allyl glycidyl ether and methacrylamide) was achieved by direct binding of enzyme via epoxy groups of support and amino, thiol and hydroxy groups on enzyme surface. Better immobilization yield was achieved by chemicaly modification of this support, introducing carbonyl group by ethylene diamine/glutaraldehyde spacer, though it was shown that its thermal stability was poorer. In the second phase, β-galactosidase was immobilized onto unmodified and modified comercial Purolite A 109 support (special, polystyrenic, macroporous anion exchange resin with primary amine weak base functional groups). Since β-galactosidase is rich in thiol (SH) groups, chemical modification was used to introduce thiol-reactive groups onto Purolite A 109 in order to achieve formation of disulfide (S-S) bonds between enzyme and support. In this phase, stability and reversibility of this immobiliyation method were evaluated. Desorption with CaCl 2 showed that adsorption of enzyme onto support is lesser, in comparison with covalent immobilization. On the other hand, desorption with DTT showed that the reversibility of the formed bonds is high, implying that this method can be used as purification method in microbial production of β-galactosidase.

57 P 27. Chemo-enzymatic epoxidation of Oleic acid catalyzed by C. antarctica lipase encapsulated in microemulsion-based organogels I. Zampakidi, M. Zoumpanioti, A. Xenakis Institute of Biological Research and Biotechnology, National Hellenic Research Foundation, Athens, Greece Epoxides are of great industrial interest because they are intermediate compounds for the production of numerous materials. This versatility is associated with the high reactivity of the oxirane ring. Specifically, fatty epoxides are used directly as plasticizers and plastic stabilizers or contribute to this domain as reaction intermediates. They are also efficient scavengers of halogens, carboxylic and mineral acids and therefore assist in preventing many damaging effects that such compounds can have on product quality, effectiveness, storage life and processing equipment. In industry, epoxidation, i.e. the conversion of double bonds to the corresponding oxirane rings, of vegetable oils has been applied using classical acid catalysts. Lately, the chemoenzymatic method has been suggested and progress was made towards reducing the limitations of industrial scale syntheses by making the procedure a more environmentally acceptable alternative for vegetable oil transformations [1]. Microemulsion-based organogels containing lipases are systems that can be successfully used as media for hosting various biocatalytic reactions. Enzymes encapsulated in these systems can retain their catalytic activity and have already been used for the catalysis of the esterification of fatty as well as phenolic acids [2, 3]. In this work, C. antarctica lipase was immobilized in hydroxyl-propyl-methyl cellulose (HPMC) organogels based on lecithin microemulsions. The potential use of these media for the catalysis of oleic acid epoxidation was investigated. The optimization of several reaction conditions such as temperature, substrate concentration and H 2 O 2 addition rate, have been examined. The linear correlation of reaction rate and enzyme concentration indicates enzymatic reaction. Although in other systems [1] the H 2 O 2 should be added drop wise in order to prevent enzyme degradation, in the case of lipase immobilized in lecithin-hpmc gels the enzyme seems to be more protected and the esterification yield is higher if the total amount of H 2 O 2 is added at the beginning of the reaction. Moreover, the increase of temperature results in an increase of the initial rate of the reaction, under constant enzyme concentration and the activation energy was calculated by the Arrhenius plot and was found to be Ea=77,2 kj/ mol. References [1] Warwel, S., Rusch gen Klaas, M. (1995) Chemo-enzymatic epoxidation of unsaturated carboxylic acids, J Mol Catal B: Enzymatic, 1, [2] Zoumpanioti, M., Karali, M., Xenakis, A., Stamatis, H. (2006) Lipase biocatalytic processes in surfactant free microemulsion-like ternary systems and related organogels, Enzyme Microb Technol, 39, [3] Zoumpanioti, M., Stamatis, H., Xenakis, A. (2010) Microemulsion-based organogels as matrices for lipase immobilization, Biotechnology Adv, 28,

58 P 28. The influence of methylglyoxal reaction with human serum albumin on its copper(ii) binding properties A.Z Penezić, J.M. Aćimović, V.B. Jovanović, Lj.M. Mandić Faculty of Chemistry, Department of Biochemistry, University of Belgrade, Serbia Processing, cooking and prolonged storage of food leads to the formation of methylglyoxal (MG). MG is also produced in some pathological states (diabetes, uremia, oxidative stress, aging and inflammation). As a highly reactive compound (α-dicarbonyls are 20,000-fold more reactive than glucose in glycation reactions) it is a potent protein and nucleic acid modifying agent. Besides ceruloplasmin, human serum albumin (HSA) represents a relatively large pool of bound copper in human plasma. HSA has one high affinity site for copper(ii), located near N-terminus (Asp-Ala-His tripeptide). Redox activity of protein bound copper is strictly regulated and its uncontrolled release can make it extremely dangerous, since it can catalyze production of free radical intermediates from molecular oxygen. The aim of this study was the investigation of influence of MG reaction with human serum albumin on its copper(ii) binding properties. HSA was preincubated with different copper(ii) concentrations to obtain HSA-copper complex. Any unbound copper was removed by ultrafiltration (10kDa cutoff). These HSAcopper complexes were then incubated with MG during six hours. Following incubation, HSA bound copper concentration was determined spectrophotometricaly with bathocuproine reagent. Also, conformational changes in HSA molecule were monitored by recording fluorescence spectra (λ ex 294 nm, λ em nm). All samples were analysed by native electrophoresis. The content of bounded copper to HSA rises with increasing concentration of added copper. Concentration of bound HSA copper decreases during the six hours incubation with MG (up to 40% of starting value). It was observed that MG had less influence on HSA bound copper release when higher copper concentration was initially preincubated with HSA. The fluorescence spectra indicate conformational changes in HSA after reaction with MG. These conformational changes could be the reason of copper leakage. Based on these findings, it was concluded that the modifications of HSA molecules with MG can lead to uncontrolled release of HSA bound copper and consequently could contribute to the production of free radical intermediates from molecular oxygen. Keywords: methylglyoxal; HSA carbonylation, HSA-copper(II) binding

59 P 29. THE DIETARY FIBER AND ANALYTICAL METHODS USED, PHYSIOLOGICAL RELEVANCE AND HEALTH BENEFITS Alexandra R. Decu 1, Marta Zachia 1 1 National Institute of Research and Development for Food Bioresources IBA Bucharest, 6 th Dinu Vintila Street, 2 nd District, RO Bucharest, Romania, tel.: , fax: , decu.andra@yahoo.co.uk The intake of dietary fiber has a number of physiological effects in humans and their effects can vary depending on the physical and chemical characteristics of the fiber components, in addition to the dose and mode of administration. Total fiber and different types of fiber can be measured in foods by established methods. In our approach, the enzymatic-gravimetric method AOAC , , , based on the gravimetrically isolation of a part of food that resist to breakdown by starch and protein degrading enzymes was used to investigate the level of dietary fiber in different types of bread. Different types of bread: wheat bread, low sodium-no salt bread, wheat bran bread, rye bread, oat bran bread and multi-grain bread were analyzed and the values for total dietary fiber are between 2.3 to 7.4 %. Keywords: dietary fiber, bread

60 P 30. Nutritive and biological values of some Pyrus varieties growing in Serbia Jovana R. Stefanović, Aleksandra R. Savić 1, Dragica M. Jakovljević, Gordana Đ. Gojgić - Cvijović, Miroslav M. Vrvić 2 IChTM, Department of Chemistry, University of Belgrade, Njegoševa 12, P. O. Box 473, Belgrade, Serbia, 1 Natural History Museum, Njegoševa 51, P. O. Box 401, Belgrade, Serbia, 2 Faculty of Chemistry, University of Belgrade, Studentski trg 16, P. O. Box 51, Belgrade, Serbia Different Pyrus varieties grown in the territory of Serbia are collected and examined from the standpoint of their nutritive and biological values. Great diversity in their morphological properties is well studied and exposed in the Collection of fruit ( ) funded in the Natural History Museum in Belgrade, where the Project Collection of fruit autochthonous and cultivated fruit of Rudnik Takovo region has been realizing since However, detailed content of some common parameters is not completely known. The aim of this study was to characterize twelve different allochthonous varieties of Pyrus species grown on the territory of Serbia. These are: Beurre Clairgeau, Abbate Fetel, General Leclerc, Beurre Bosc, Conference, Beurre d` Hardepont, Williams Christbirne Bartlett, Doyenne du Comice, Kifer, Packham s Triumph, Curé, Passe Crassane. These varieties are commercial, and have the same origin (Pyrus communis L.). Most of them grows in Serbia since 18 th or 19 th century, but some of them are new (e.g. Packham's Triumph). Morphological and organoleptic properties, as well as basic chemical composition and energetic values, indicated significant difference between species. This is very important for their potential use in food industry, such as production of juices, sweets, jams, alcoholic beverages, etc. In order to characterize these pear varieties in more detail, the content of organic acids, proteins, carbohydrates (total sugar content, glucose, fructose, pectin, insoluble dietary fibers), lipids, minerals and vitamin C was determined by standard methods. Although the differences in the chemical composition of samples were found, the obtained results indicate that all of Pyrus varieties are suitable for potential industrial processing - high content of carbohydrates (55 71 g / 100 g dry matter basis) makes them usable for preparing different fruit products, as well as fermentation beverages. Pectin ( g / 100 g) and fiber content ( g / 100 g), which differs among varieties, is very important for gelling, thickening and stabilizing of pear products, as well as for functionality of these fruits.

61 P 31. Biogenic amines in commercial dry fermented sausages as possible precursors of N-nitrosamines? Eveline De Mey 1, Lore Dewulf 1, Gabriela Drabik-Markiewicz 2, Teresa Kowalska 2, Hubert Paelinck 2 1 Research Group for Technology and Quality of Animal Products, Catholic University College Ghent, Gebroeders Desmetstraat 1, B-9000 Ghent, Belgium 2 Institute of Chemistry, University of Silesia, 9 Szkolna Street, Katowice, Poland Objectives Fermented meat products can contain elevated levels of biogenic amines and their consumption can result in food intoxication. Moreover, biogenic amines can react with nitrite to form carcinogenic N-nitrosamines. In this study the residual nitrite and nitrate, together with biogenic amines and N-nitrosamines were determined, to examine the safety of fermented sausages. Materials and Methods Samples were analyzed at the end-of-shelf life. Biogenic amines, NO 2 - and NO 3 - were analyzed by HPLC-UV. The N-nitrosamines were detected by GC-TEA. Predictive Analysis Software (PASW Statistics , SPSS Inc.) was used to calculate the Spearman s correlation coefficients. Results and conclusions The dry sausages contained residual nitrite and nitrate levels varying from not detected to 147 NaNO2 mg/kg, resp. 168 NaNO3 mg/kg. In general the biogenic amine concentrations were low. Only for putrescine and cadaverine, levels up to 316 mg/kg, resp. 641 mg/kg, were measured. These high levels are a risk for human health since both biogenic amines aggravate histamine and tyramine food poisoning. N-nitrosamines were only occasionally quantified. Although it is assumed that cadaverine, putrescine, spermidine and spermine are precursors of N-nitrosamines, no relationship was observed. On the other hand a significant correlation between the residual - level of NO 2 and the presence of N-nitrosodimethylamine (p<0.05), N-nitrosodibutylamine (p<0.01), N-nitrosopyrrolidine (p<0.05) and N-nitrosomorpholine (p<0.05) was observed. Nevertheless the detected amounts of these carcinogenic compounds in the commercial meat products remained low.

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63 Photo Gallery Registration and opening of the workshop Session 1 Plant food chemistry and biochemistry

64 Session 2 Animal food chemistry and biochemistry

65 Session 3 Food analysis Session 4 Food biotechnology

66 Session 5 Dairy Industry Coffee breaks and poster sessions

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68 Closure of the workshop and award ceremony Senior and junior researchers at farewell cocktail