Comparison of phenolic compounds, antioxidant and antidiabetic activities between selected edible beans and their different growth periods leaves

- Polyphenols profile, antioxidant, and α-glycosidase inhibitory activities in leaves were examined firstly.
- The identification and quantification of so many isoflavones and flavones derivatives were performed in the leaves firstly.
- Adzuki bean leaves exhibited stronger antioxidant and α-glucosidase inhibition activities than seeds.
- Soyabean displayed a more positive effect on antioxidant and α-glucosidase inhibition activities than leaves.

The aim of this study was to determine and compare a polyphenolic profile, antioxidant and antidiabetic activities between seeds and different growth periods leaves (from week 3 to 14) of three selected edible beans: yellow and black soyabean (Glycine max), as well as adzuki bean (Vigna angularis). Polyphenolic profile was determined by HPLC-ESI-TOF-MS and HPLC-DAD, antioxidant activity were analysed by ABTS (2,2′-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid)), FRAP (ferric reducing antioxidant power), and DPPH (2,2-diphenyl-1-picrylhydrazyl) tests. We also evaluated for their antidiabetic activity against α-glycosidase. The results showed that the leaves of three edible beans were a valuable source of polyphenolic substances. Furthermore, adzuki bean leaves contained significantly higher polyphenol content than their seeds. Thus, they exhibited stronger antioxidant and α-glucosidase inhibitory activities than seeds. However, soyabean contained more polyphenols than their leaves. Therefore, soyabean displayed a more positive effect on antioxidant and α-glucosidase inhibitory activities than their leaves.