汇报 人：胡冬梅 指导老师：薛照辉副教授

1. A comparative assessment of total phenolic content, ferric reducing-anti-oxidative power, free radical scavenging activity, vitamin C and isoflavones contentin soybean with varying seed coat colour 汇报人：胡冬梅 指导老师：薛照辉副教授

2. Contents Introduction 1 Materials and methods 2 Results and discussion 3 Conclusions 4 2011-10-23

3. 1. Introduction soy peptides isoflavones lecithin soybean tocopherols saponins vitamin C 2011-10-23

4. 1. Introduction black green yellow Furuta et al. (2003) soybean-boiled extracts and boiled soybean homogenate of all three types of soybean Xu et al. (2007) 2 yellow and 1 black Xu and Chang (2008a, 2008b) 28 yellow and 2black FRAP FRSA TPC 2011-10-23

5. Diagram vitamin C is a strong scavenger of free radicals 6 genotypes from each type of soybean FRAP FRSA TPC forms of isoflavones vitamin C . the number of black soybean genotypes analysed were too few soybean with green seed coat were not included 2011-10-23

6. 2. Materials and methods the seeds were dried in oven at 70 ℃ till the weight became constant. Moisture free seeds were secured in screw-capped vials 2011-10-23

7. 2.1. Extraction of antioxidants from the seeds Oven dried seeds ground into flour pass through 100-mesh sieve Both the extracts were combined and stored at 4 ℃ in dark for analyses residues were re-extracted with 5 ml 70% acetone extracted with 15 ml aqueous acetone at 25℃ in the dark overnight centrifuged at 3000r for 10 min 2011-10-23

8. 2.2 Determination of TPC 0.05 ml 70% acetone soy extract 0.5 ml F–C reagent and 0.5 ml 20% Na2CO3 final volume was 5 ml with distilled water incubation for 30 min at room temperature 700nm distilled water gallic acid equivalents 2011-10-23

9. 2.3 Ferric reducing-antioxidant power assay absorbance was recorded at 593 nm . 0.1 ml of soybean flour extract + 3ml FRAP reagent 300 mM acetate buffer 10 mM TPTZ in 40 mMHCl and 20 mM FeCl3· 6H2O in the ratio 10:1:1 incubated for 15 min at 37 ℃ 2011-10-23

10. 2.4. DPPH free radical-scavenging activity • 0.1 ml of the extraction solvent • adding DPPH solution incubation10 min at room temperature • Decrease in absorbance at 517 nm (ethanolic as blank) 2011-10-23

11. where Acontrolis absorbance of the control Asampleis the absor-bance of the sample after. 2011-10-23

12. 2.5 HPLC determination of isoflavones 2.5.1. Sample preparation drie in an oven at 70 ℃ ground and pass through 100-mesh sieve Extract with 80% ethanol (5 ml) and concentrated HCl (1 ml) for 2h in a boiling water bath suspension was colleted centrifuge at 10,000 rpm for 10 min Further test 2011-10-23

13. 2.5.2. HPLC conditions • 20ul • C-18 silica column • column oven was maintained at 40℃ • flow rate:0.8 ml/min for 25 min • solvent A (10% ACN) (乙腈) • solvent B (38% ACN) • The solvent system(% solvent A/solvent B): • 0 min (0/100), 5 min(10/90), 20 min (0/100), and 25 min (0/100). • 260 nm 2011-10-23

14. 2.5.2.1. Vitamin C • Vitamin C was quantified by using standard 2,6dichlorophenol-indophenol dye method 还原型抗坏血酸能还原染料2.6-二氯酚靛酚，该染料在酸性中呈红色，被还原后红色消失。还原型抗坏血酸还原2.6-二氯酚靛酚后，本身被氧化成脱氢抗坏血酸。在没有杂质干扰时，一定量的样品提取液还原标准2.6-二氯酚靛酚的量与样品中所含维生素C的量成正比。 2011-10-23

15. 3. Results and discussion 1.06-1.54 1.10-3.11 16.42-44.05 1.38 2.55 31.19 21.08-32.55 0.96-2.89 4.02-6.44 26.37 5.14 1.61 0.81-5.89 2.87-6.15 59.71-83.47 2.82 4.56 75.10 2011-10-23

16. 282.5 1:1.1:1.5 309.6 453.4 1.5:1:2.2 478.8 220.9 321.9 250.5 1:1.4：1.9 358.4 475.4 2011-10-23

17. 类胡萝卜素， 叶黄素 2011-10-23

18. 2011-10-23

19. 4. Conclusions antioxidant constituents other than isoflavones contribute to the higher FRSA in black soybean. yellow soybean exhibited lower FRAP value than black and green soybean. black seed exhibited higher FRSA than yellow and green soybean. 2011-10-23

20. 4. Conclusions • every black genotype does not necessarily contain higher level of TPC than yellow or green soybean. • some black genotypes despite having low TPC than green soybean showed higher levels of FRSA. ? 2011-10-23

21. Thank You !