Organic acids make more sour taste than ascorbic acid in Thai indigenous plants

Transcription

1 H rganic acids make more sour taste than ascorbic acid in Thai indigenous plants H H H H H Benyathip Sukontaprapun, Kunchit Judprasong*, Somsri Charoenkiatkul Institute of Nutrition, Mahidol University (INMU), Phutthamonthon 4 Rd., Salaya, Phutthamonthon, Nakhon Pathom Thailand kunchit.jud@mahidol.ac.th 1

2 rganic acids rganic compounds have at least one carboxylic functional group (RCH). rganic acids are primary metabolites component that contributed to plant growth. They are found in great amount in all plants especially in vegetables and fruits and other manufacture products such as vinegar, salad dressings. H H H H H H H H H H H H H H xalic Citric Malic Succinic Formic Acetic 2

3 Benefits of rganic acids Some organic acid may be used as indicators for ripeness and they may also prevent darkening and enzymatic browning produced after cooking of potatoes (Silva et al., 1991). They can stabilize vitamins B and C and decrease possible destruction of vitamins from heat and light (Shoufeng et al., 2011). These organic acids can improve mineral absorption (Shoufeng et al., 2011). 3

4 Energy from organic acids Greenfield & Southgate book (2003) mentioned that organic acids should be included in energy calculations. Energy (kcal/100g) = CH x 4 + Fat x 9 + Protein x 4 + Alcohol x 7 + rganic acid x 3 4

5 Why we are interesting in organic acid? rganic acids can influence sensory properties of fruits and vegetables which could have sour and tart flavors. Most of indigenous plant has strong sour taste but some of them contained high vitamin C. Vitamin C 745 mg/100g (Charoenkiatkul S, et al.2012) rganic acid? Tewdeang (Thai name) (Cratoxylum formosum (Jack) Dyer): Commonly consumed as fresh 5

6 Why we are interesting in organic acid? Another indigenous plant also has strong sour taste but very low amount of vitamin C (Charoenkiatkul et al. 2012). Vitamin C 13 mg/100g Mamao (Thai name) (Antidesma ghaesembilla Gaertn.): Commonly eaten as fresh or fruit juice rganic acid? Most of people believed that if food has a sour taste, it also contained high amount of vitamin C??? 6

7 bjectives 1. To determine individual organic acid in indigenous plants collected from 2 conservative areas in Thailand. 2. To see the correlation between each organic and vitamin C contents. 7

8 Study area Kanchanaburi province Amnatchareon province Srinakarind dam Wangkhamen Mountain 8

9 Material & methods 55 indigenous plants samples 1) 8 types of young leavesconsumed plants 2) 4 types of flowerconsumed plants 3) 11 types of fruitconsumed plants 4) 1 type of podconsumed plants 5) 3 types of tuberconsumed plants 6) 2 types of young stemconsumed plants 9

10 Example of young leavesconsumed plants No. Thai name Scientific name Picture Sour taste? 1. Pakwanpa Melientha suavis Pierre No 2. Takeuk Albizia lebbeck (L.) Benth No 3. Krapeejan Millettia brandisiana Kurz Yes 4. Kradon Careya sphaerica Roxb. Yes 10

11 Example of fruitconsumed plants No. Thai name Scientific name Picture Sour taste? 5. Makarmpom Phyllanthus emblica L. Yes 6. Makokpa Spondias pinnata Kurz Yes 7. Mamao Antidesma velutinosum Blume Yes 11

12 Analysis of organic acids by HPLC method 12 1) Extraction organic acids: 1 g freeze dried sample + 50 ml HCl (2M) 80 C for 15 minutes 2) rganic acids determination: Inject extract sol. 20 µl Crude extract Supernatant Centrifugation Filtrated through a 0.45 µm cellulose acetate membrane HPLC (UV detector at 210 nm) Column: Aminex HPX87H, 300 mm 7.8 mm (Anion exchange column) Mobile phase: M sulfuric acid Isocratic elution at 0.5 ml/min Extracted solution 1 Savage et al., JFCA, Judprasong.et al., JFCA, 2006 Calculation each organic acid by using peak area compare to standard calibration curve 12

13 Chromatogram of organic acid Standards Sample Selectivity & Specificity 13

14 Percent recovery study Results & Discussion rganic acids xalic acid Citric acid Malic acid Succinic acid LD LQ % Recovery (mg/100 g) ± SD ± ± ± ± 7.3 Acceptable recovery is % at the conc. level of 0.1% (AAC, Guidelines for Single Laboratory Validation of Chemical Methods for Dietary Supplements and Botanicals, 2002). Formic acid Acetic acid ± ± 3.5 Accuracy LD = Limit of detection (3 S 0 ) and LQ = limit of quantitation (10 S 0 ) 14

15 Inhouse quality control sample Inhouse QC sample: Chamoung (Garcinia cowa Roxb.) leaf It contained significant amounts of most organic acids It was analysed along with unknown samples in each run. Each organic acid content is stayed within the +2 SD, with the relative standard deviation of less than 9% Precision 15

16 Makarmpom: F H H Fruits consumed plants Results: xalic acid Vitamin C (mg/100g) 575 ± 152 Sour taste Makokpa: F ± 10 Mamao: FR ± 1 Mamao: FY ± xalic content (mg/100g FW) Leaves consumed plants Sommong: FY ± 1 Sommong: BLY Wanpro: FY Wanpro: FM ± 1 4 ± 1 4 ± xalic content (mg/100g FW) = sour taste ranking = no sour taste *F = Fresh, FR = Fresh ripped, FY = Fresh young, BLY = Blanched young, FM = Fresh mature, 16

17 H H H H Results: Citric acid Fruits consumed plants Vitamin C (mg/100g) Sour taste Mamao: FY ± 1 Mamao: FR Makokpa: F ± 1 37 ± Citric acid content (mg/100g FW) Flowers consumed plants Vitamin C (mg/100g) Sour taste Pakwanpa: F Pakwanpa: BL Citric acid content (mg/100g FW) = sour taste ranking = no sour taste *FY = Fresh young, FR = Fresh ripped, BL = Blanched, 17

18 Results: Malic acid Kradon: FY 6385 Tewdeang: FY 1361 Tewkaw: F 1083 Enoon: BL 571 Takuek: F 391 Takuek: FY 225 Pakwanpa: Malic acid acid content (mg/100g FW) Pakwanpa: B 984 Pakwanpa: F 619 Sanyai: B 865 Leaves consumed plants Fruits consumed plants Vitamin C (mg/100g) Sour taste Malic acid acid content (mg/100g FW) *FY = Fresh young, F = Fresh, BL = Blanched, B = Boiled = sour taste ranking = no sour taste 18

19 Results: Succinic acid Family of Guttiferae Leaves consumed plants Vitamin C (mg/100g) Tewdeang: FY 2454 Tewkaw: F 2330 Tewmon: F 1689 Kradon: FY 271 Pakkood: FY 186 Pakkood: BY Sour taste Succinic acid content (mg/100g FW) = sour taste ranking = no sour taste Health Benefit: Against ischemia/reperfusion cardiac injury (Sakamoto M., et al., 1998) *FY = Fresh young, F = Fresh, BY = Boiled young 19

20 Results: Formic acid Cheedin: F Songfa: F Leaves consumed plants Vitamin C (mg/100g) Not detected Not detected Sour taste Kradon: FY Sommong: BLY Sommong: FY Formic acid content (mg/100g FW) Fruits consumed plants = sour taste ranking = no sour taste Mamao: FR Mamao: FY Fakkawlookon: BY Not detected Formic acid content (mg/100g FW) *F = Fresh, FY = Fresh young, BLY = Blanched young, FR = Fresh ripped, BY = Boiled young 20

21 Results: Acetic acid Flowers consumed plants Vitamin C (mg/100g) Sour taste Pakwanpa: F Pakwanpa: BL Acetic acid content (mg/100g FW) Fruits consumed plants Vitamin C (mg/100g) Sour taste Mamao: FY Mamao: FR Fakkawlookon: BY Not detected Acetic acid content (mg/100g FW) Health Benefit: increase absorption of mineral (Sakamoto M., et al., 1998) *F = Fresh, BL = Blanched, FY = Fresh young, BY = Boiled young 21

22 Correlation between vitamin C and organic acid contents Correlation coefficient (r) Samples containing Samples containing All samples Parameters vitamin C <100 mg/100g vitamin C >100 mg/100g (n=38) (n=28) (n=10) Sum of organic acids xalic acid Citric acid Malic acid Succinic acid Formic acid Acetic acid

23 Indigenous samples Makarmpom: fresh fruits Moist. rganic acid (mg/100g FW) Vit. C (g/100g) xalic Citric Malic Succinic Formic Acetic Sum (mg/100 g) Sour taste Energy ranking increase (Kcal) Kradon: fresh flowers Mamao: fresh young fruits Mamao: fresh ripe fruits Tewdeang: fresh young leaves Tewkaw: fresh leaves Tewmon: fresh leaves Wanpro: fresh young leaves Makokpa: fresh fruits Wanpro: fresh mature leaves Takeuk: fresh young leaves Selected indigenous plants

24 Conclusion 1. Data of each organic acid in 55 Thai indigenous plant samples is firstly reported and compiled in the Thai FCDB. 2. There are no correlation between vitamin C and each organic acid except succinic acid at high amount of vitamin C. 3. Sour taste of plants cannot indicate that plants contain high vitamin C. 4. Energy obtained from organic acid may contribute total energy especially the one that has high organic acids. 24

25 Thank you very much for your attention. Contact: Kunchit Judprasong Institute of Nutrition, Mahidol University (INMU), Phutthamonthon 4 Rd., Salaya, Phutthamonthon, Nakhon Pathom Thailand kunchit.jud@mahidol.ac.th 25