ESSENTIAL OIL AND EXTRACT OF CORIANDER (Coriandrum sativum L.) INTRODUCTION

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1 ESSENTIAL OIL AND EXTRACT OF CORIANDER (Coriandrum sativum L.) Zoran Zeković a *, Dušan Adamović b, Gordana Ćetković a, Marija Radojković a and Senka Vidović a a University of Novi Sad, Faculty of Technology Novi Sad, Buleva cara Lazara 1, Novi Sad, Serbia b Institute of Field and Vegetable Crops, Maksima Gorkog 30, Novi Sad, Serbia Two different methods of coriander (Coriandrum sativum L.) essential oil isolation, steam distillation and extraction by methylene chloride (Soxhlet extraction) were investigated. After the determination of essential oil content in the investigated drug and in dry extract (using steam distillation), qualitative and quantitative composition of obtained essential oils, determined by TLC and GC-MS methods, were compared. The content of linalool was higher (52.4%) in essential oil obtained by coriander steam distillation than that in essential oil separeted from dry extract (42.8%), and, on the other hand, content of geranyl-acetate was lower (4.6% and 11.7%, respectively). KEY WORDS: Coriander, essential oil, extract, TLC, GC-MS INTRODUCTION Coriander (Coriandrum sativum L.) is a well-known aromatic/medicinal plant, which grows in mediterranean countries, and possesses a lot of pharmacological activities. In tradicional medicine, seeds are used in the treatment of gastrointestinal problems, rheumatism and joint pains. It has been reported that they exhibit a hypoglycaemic action and influence on carbohydrate metabolism, whereas the antimicrobial effect exibit both leaves and seeds. Besides, leaves and seeds are used to flavour various commercial foods, as liqueurs, teas, meat products and pickles (1). Isolation of coriander essential oil using different extraction methods (steam distillation and supercritical fluid extraction SFE) and determination of essential oil compounds (using GC-MS method, in the first place) were investigated in (1,2). The dominant coriander seeds essential oil compounds are: linalool, as a really predominant compound (up to 70%, some essential oil samples even more), geranyl acetate (up to 11%), and geraniol, borneol, citronellol, -pinene and camphor, all in much lower percent (1-3). In this paper, two methods of coriander essential oil isolation (steam distillation and extraction by methylene chloride, i.e. Soxhlet extraction), as well as the results of qualitative and quantitative analyses of obtained essential oil samples, are reported. * Corresponding author: Dr. Zoran Zekoviš, Prof., University of Novi Sad, Faculty of Technology Novi Sad, Department of Biotechnology and Pharmaceutical Engineering, Novi Sad, Bulevar cara Lazara 1, Serbia, zzekovic@tf.uns.ac.rs 281

2 EXPERIMENTAL Plant Material and Chemicals Coriander (Coriandrum sativum), i.e. coriander seeds were produced by the Institute of Field and Vegetable Crops, Novi Sad, Serbia (year 2009). Seeds were air-dried, milled and mean particle size (0.615 mm) were determined by sieve set (Erweka, Germany). All chemicals were of analytical reagent grade. Determination of essential oil content The content of essential oil in the investigated drug, as well as in coriander seeds dry extract obtained by methylene chloride, was determined by the officinal procedure given by Ph. Jug. IV (4). Extraction with methylene chloride Sample of coriander seeds (20.0 g) was extracted by methylene chloride (110 ml) using Soxhlet apparatus. After 18 exchanges of the extract, the solvent was evaporated under vacuum and the obtained extract was dried under vacuum (50 o C, 24 hours), resulting in the dry extract. Thin Layer Chromatography (TLC) Glass plates (20x20 cm) were coated in our laboratory using Silica gel G (Merck, Germany), thickness 0.25 mm. Essential oil samples were dissolved in methylene chloride (ratio 1 : 10) and essential oil solutions (about 20 L) were spotted on the plate as a start point or line. The mobile phase was toluene:ethylacetate (93:7; V/V). The development was performed at room temperature (about 20 o C) in a glass chamber. Detection was done by spraying the plate with 1% vanillin solution (1 g of vanillin was dissolved in 99 g mixture of 95% ethanol and cc. sulphuric acid, ratio 9:1; w/w). After spraying, the plate was heated at 110 o C for 5-10 min. Gas Chromatography-Mass Spectrometry (GC-MS) The instrument was GC-MS Agilent Technologies series 6890N/5975B (Santa Clara, California, USA). An HP-5 MS column (30.0 m x 0.25 mm, film thickness 0.25 µm) was used. Helium flow rate: 1.1 ml min -1. Temperature: injector 250 o C; detector 280 o C, initial 50 o C with a linear increase of 10 o C min -1 to 130 o C (8 min) and 12 o C min -1 until the final 280 o C (12.5 min). Total analysis time: 20.5 min. The injected volume of essential oil sample solution in methylene chloride (about 0.5 mg ml -1 ) was 1 L, using split-ratio 10:1. Detector: D. The compounds were identified using the NIST/NBS Wiley data base. The results of compound content were expressed as relative percent (%). 282

3 RESULTS AND DISCUSSION The steam distillation is, usually, an official method for essential oil content determination, as well as for industrial essential oil production. However, because of the unpolar nature of essential oil compounds, different ways of aromatic plants extraction by unpolar solvent(s) for obtaining a product (liquid or, in the first place, dry extract) are used. Hence, the obtained extract contains essential oil and other compounds from started drug, depending on the solvent used. These classical procedures for separation of active substances from the plant material (steam distillation and extraction with organic solvents) have serious drawbacks. The distillation procedure allows only the separation of volatile compounds (essential oils), which, to a greater or lesser extent, are transformed under the influence of the elevated temperature. On the other hand, extraction with organic solvents can hardly render an extract free of traces of the organic solvent, which are undesirable for either organoleptic and/or health reasons. Besides, organic solvents are insufficiently selective, so that, in addition to the active substances, they also dissolve some concomitant compounds. For these reasons supercritical fluid extraction (SFE) has recently gained in importance as an alternative to the classical procedure, as a relativelly new and good method for the extraction of medicinal plants (and other materials) (5-10). Isolation of essential oil from coriander seeds, as the dominant mixture of pharmacologically active compounds, was investigated. After the determination of drug moisture content (7.04%), the coriander sample was milled and mean particle size was obtained (0.615 mm). After that, the content of essential oil was determined by steam distillation (0.99%; V/w). The essential oil content quoted in the literature (3) ranges from 0.8 to 1.0%. The main compounds of coriander essential oil (in the first place as predominant compound linalool, geraniol and geranyl-acetate) were detected by TLC analysis (Table 1). Table 1. Identification of coriander essential oil compounds by TLC Compound R f value (literature) Colour (literature) R f value (experiment) Colour (experiment) Geraniol 0.20 Grey-blue 0.23 Gray-violet Linalool 0.35 Blue 0.40 Blue-violet Geranyl-acetate 0.70 Grey-blue 0.75 Grey-blue The qualitative and quantitative analyses of coriander essential oil were done by GC- MS method (Figure 1a and Table 2). The relative percent of the main coriander essential oil compounds is: linalool (52.4%), limonene (8.6%), camphor (7.1%), -terpinene (7.2%), geraniol (9.0%) and geranyl-acetate (4.6%). This analysis confirmed the results of TLC. Our unpublished results show that this essential oil contained a very low concentration of total phenol compounds (only 1.81 mg gallic acid equivalents per 1 g of essential oil). 283

4 A b u n d a n c e 1. 8 e T I C : K O R I J A N D E R E U. D \ d a t a. m s 1. 7 e e e e e e e e T im e - - > a) A b u n d a n c e 1. 8 e T I C : K O R I J A N D E R S E. D \ d a t a. m s 1. 7 e e e e e e e e T im e - - > b) Figure 1. GC chromatogram of: a) coriander essential oil obtained by steam distillation and b) essential oil separated by steam distillation from dry extract obtained by methylene chloride 284

5 Table 2. Results of essential oil composition obtained by GC-MS analysis Compound Percent content (%) EO* by steam distillation EO from DE** Monoterpenes α-pinene Camphene Sabinene Myrcene trans-β-ocymene Terpinene Terpinolene Phellandrene Limonene Oxygenated monoterpenes Linalool Camphor Terpinen-4-ol Geraniol Geranyl acetate Pinocarvone Borneol cis-sabinene hydrate α-terpineol Citronellol Nerol Geraniol Myrtenyl acetate Aliphatics Decane Nondecane Eicosane Dodecyl aldehyde TOTAL * - Essential oil (see Figure 1a) ** - Dry extract (see Figure 1b) By Soxhlet extraction with methylene-chloride, the extraction yield, i.e. the yield of coriander dry extract was 5.10% (w/w). The essential oil was separeted from this extract by steam distillation and content of essential oil in the coriander dry extract was determined (16.67%; V/w). The obtained content of essential oil was used to calculate the essential oil content in the starting drug, i.e. coriander seeds (0.85%; V/w). This result shows some lower contant of essential oil in the investigated drug than that determined by the official method (0.99%). The results of GC-MS analysis of this essential oil are 285

6 presented in Figure 1b and Table 2. Besides the content of essential oil, content of the dominant compounds was different than that of the coriander essential oil obtained by steam distillation, too. Content of linalool was lower (42.8%), of limonene similar (8.5%), of camphor higher (8.2%), of -terpinene higher (10.6%), of geraniol lower (3.5%) and of geranyl-acetate higher (11.7%). Contents (%) of different dominant compound groups in coriander essential oil obtained by steam distillation and essential oil separated by steam distillation from methylene chloride dry extract are shown in Figure 2. Oxygenated monoterpenes are a dominant compound group in both investigated samples of essential oils (77.20% in coriander essential oil and 69.30% in essential oil separated from dry extract). 0.50% 21.50% a) 77.20% 0.30% 27.20% Monoterpenes Oxygenated monoterpenes Aliphatics b) 69.30% Figure 2. Content (%) of different dominant compound groups in: a) coriander EO obtained by steam distillation; b) EO separated by steam distillation from dry extract (DE) obtaned by methylene chloride CONCLUSION The coriander essential oil content determined by official method is higher (0.99%) than content of essential oil obtained by steam distillation from dry extract (0.85%). Based on the GC-MS analysis, the major compound of both essential oils is linalool (52.4% in coriander essential oil and 42.8% in essential oil separated from dry extract). Oxygenated monoterpenes are dominant compound group in both investigated samples of essential oils. Qualitative composition of investigated essential oils was the same, but contents of essential oil compounds were different. 286

7 Acknowledgement The authors would like to thank the Ministry of Education and Science, Republic of Serbia, for financial support (Project No. TR31013). REFERENCES 1. Ferraro, V., Grosso, C., Burillo, J., Urieta, J.S., Langa, E., Figueiredo, A.C., Barroso, J.G., Coelho, J.A., Palavra, A.M.: Comparison Betweeen Coriander Volatile Oils Obtained by Supercritical CO 2 Extraction and Hydrodistillation, fileadmin/files/docs/colmar/paper/n18.pdf 2. Zorca, M., Gainar, I., Bala, D.: Supercritical CO 2 extraction of essential oil from coriander fruits, Analele Universitatii din Bucuresti Chimie, Anul XV, vol. II (2006) Wagner, H., Bladt, S., Zgainski, E.M.: Plant Drug Analysis A Thin Layer Chromatography Atlas, Springer-Verlag, Berlin Heidelberg New York Tokyo (1984). 4. Pharmacopoeia Jugoslavica, Editio quarta (Ph. Jug. IV), Savezni zavod za zdravstvenu zaštitu, Beograd, 1984 (in Serbian). 5. Zekoviš, Z., Lepojeviš, Ţ., Vujiš, Đ.: Supercritical Extraction of Thyme (Thymus vulgaris L.), Chromatographia 51, 3/4 (2000) Zekoviš, Z., Lepojeviš, Ţ., Mujiš, I.: Laurel Extracts Obtained by Steam Distillation, Supercritical Fluid and Solvent Extraction, Journal of Natural Products 2 (2009) Jokiš, S., Zekoviš, Z., Vidoviš, S., Sudar, R., Nemet,I., Biliš, M., Veliš, D.: Supercritical CO 2 extraction of soybean oil: process optimisation and triacylglycerol composition, International Journal of Food Science and Technology 45, 9 (2010) Vidoviš, S., Mujiš, I., Zekoviš, Z., Lepojeviš, Ţ., Miloševiš, S., Jokiš, S.: Extraction of Fatty Acids from Boletus edulis by Subcritical and Supercritical Carbon Dioxide, J. Am. Oil Chem. Soc. 88 (2011) Zekoviš, Z.: Chamomile Ligulate Flowers in Supercritical CO 2 -Extraction, Journal of Essential Oil Research 12, 1 (2000) Zekoviš, Z., Pfaf-Šovljanski,I., Grujiš, O.: Supercritical fluid extraction of hops, Journal of Serbian Chemical Society 72, 1 (2007)

8 ЕТАРСКО УЉЕ И ЕКСТРАКТ КОРИЈАНДЕРА (Coriandrum sativum L.) Зоран Зековић a, Душан Адамовић б, Гордана Ћетковић а, Марија Радојковић а и Сенка Видовић а a Универзитет у Новом Саду, Технолошки факултет, Булевар цара Лазара 1, Нови Сад, Србија b Институт за ратарство и повртарство, Максима Горког 30, Нови Сад, Србија Испитана су два поступка за добијање етарског уља коријандера (Coriandrum sativum L.), дестилација воденом паром и екстракција метилен хлоридом (Soxhlet екстракција). Након одређивања садржаја етарског уља (ЕУ) у испитиваној дроги и сувом екстракту (СЕ) после Soxhlet екстракције, квалитативни и квантитативни састав узорака је одређен применом TLC и GC-MS анализе, а добијени резултати су упоређени. Садржај линалоола је већи (52,4%) у ЕУ коријандера добијеног дестилацијом воденом паром у односу на његов садржај у ЕУ издвојеном из СЕ (42,8%), док је садржај геранил ацетата у СЕ већи (11,7%) у односу на садржај овог једињења у ЕУ (4,6%) добијеног дестилацијом помоћу водене паре. Кључне речи: коријандер, етарско уље, екстракт, TLC, GC-MS Received 26 September 2011 Accepted 27 October