Comparison of saponin contents of different varieties of momordica charantia l. and their inhibition on α-glucosidase activity

Chinese. 【目的】比较35个苦瓜品种的果肉和籽粒中皂苷含量及其对α-葡萄糖苷酶活性抑制作用的差异。【方法】选用华南地区的35个主要苦瓜品种为材料，分别测定其果肉和籽粒中皂苷含量及对α-葡萄糖苷酶的抑制率，其中皂苷含量测定采用高氯酸-香草醛-冰醋酸法，而对α-葡萄糖苷酶的抑制率测定采用比色法, 品种之间的差异采用新复极差法，果肉和籽粒两个组织部位之间差异采用t检验，品种聚类分析采用系统聚类法。【结果】不同品种果肉和籽粒中皂苷含量及其对α-葡萄糖苷酶的抑制率之间表现出显著的基因型差异，其中果肉和籽粒中皂苷含量变幅分别为1.17%～4.07 %和0.16%～1.54%，变异系数分别为32%和38%，平均值分别为1.96%和0.74%；对α-葡萄糖苷酶的抑制率变幅分别为2.40%～34.53%和7.77%～30.07%，变异系数分别为46%和36%，平均值分别为17.96%和14.96%；果肉中的皂苷含量及对α-葡萄糖苷酶的抑制率显著高于籽粒；通过系统聚类法可将35个苦瓜品种聚为4类，分别包含16、6、12和1个品种。【结论】不同苦瓜品种的皂苷含量及对α-葡萄糖苷酶的抑制率存在显著差异，且同一苦瓜品种果肉中的皂苷含量及对α-葡萄糖苷酶的抑制率高于籽粒。

English. [Objective] To study the difference in saponin contents of 35 varieties of Momordica charantia L. and their inhibitory effects on ct-glucosidase activity. [Method] Perchloric acid-vanilin-glacial acetic acid method was used to determine saponin content, while the inhibitory effect of α-glucosidase activity was conducted by colorimetric method. The paired t-test and system clustering procedure were used for this experiment. [Result] There is a significant difference in contents and their inhibitory effects on α-glucosidase. Activity of saponin extracted from pulp and seed of Momordica charantia L. in different varieties existed. The content ranges of saponin were 1.17%-4.07% and 0.16%-1.54%, with the coefficients of variability being 32% and 38%, while the average values were 1.96% and 0.74%, respectively. The ranges of their inhibition effects on α-glucosidase activity were 2.40%-34.53% and 7.77%-30.07%, with the average values being 17.96 and 14.96%, respectively. The saponin contents and inhibition effect on α-glucosidase activity by pulp extract were significantly higher than by seed. Thirty-five varieties of Momordica charantia L. were clustered into 4 clusters consisting of 16, 6, 12 and 1. [Conclusion] The contents and inhibitory effects on α-glucosidase activity of saponin were significantly different among different Momordica charantia L. varieties and were higher in pulp than in seed.