Kuguacin N

Scientia Agricultura Sinica, 2017.

Saponion Profiles and Antioxidant Activity,α-Glucosidase Inhibitory Activity of Momordica charantia of Different Varieties[Reference: WebLink]

The content and composition of saponion of 13 different M. charantia varieties as well as the antioxidant activity and inhibitory effect of α-glucosidase were studied.
METHODS AND RESULTS:
Perchloric acid-vanilin-glacial method was used to determine saponin content, while HPLC method was used to measure the contents of 7 saponin components. In addition, their antioxidant activity was evaluated by oxygen radical absorbance capacity (ORAC). The 4-nitrophenyl-2-β-D-glucopyranoside method was used to measure the a-glucosidase inhibitory activity and to analyze the relationship between the components and the corresponding activity. There is a significant difference in contents of saponin in 13 different varieties of M charantia.The content ranges of saponin were 0.52-1.20 g/100g DW, with an average value being 0.79 g/100g DW, and the coefficient of variability being 21.65%. The average contents of components were as follows: momorcharaside A 5.32 μg•g⁻¹ DW, momordicoside A 25.42 (μg•g⁻¹ DW, karaviloside XI 3.96 μg•g⁻¹ DW, momordicoside F2 66.95 μg•g⁻¹ DW, momordicoside K 183.70 μg•g⁻¹ DW, (23E)-3p,7p,25-trihydroxycucubita-5,23-dien-19-al 40.13 μg•g⁻¹ DW, and Kuguacin N 3.87 μg•g⁻¹ DW. ORAC values of the 13 M. charantia varieties varied from 2 747.76 to 15 584.07 μmol Trolox•g⁻¹, the average value being 8 879.48 mol Trolox•g⁻¹, the coefficient of variability being 34.91% and the IC50 value of alpha glucosidase varied from 1.55 to 4.96 mg•mL⁻¹.
CONCLUSIONS:
Significant differences in the components of saponin and the antioxidant activity and the inhibitory effect on α-glucosidase of different varieties of M. charantia were detected. Saponin is the main active basis of a-glucosidase activity in M. charantia, but not the main antioxidant substance. (23E)-3p,7p,25-trihydroxycucubita-5,23-dien-19-al is the major active compound.