Comparative analysis of phenolic content and in vitro bioactivities of Bidens pilosa L. flowers and leaves as affected by extraction solvents

Bidens pilosa L., native to South America, is valued for its purposes as a food and medicine. The study aimed to examine phenolics, antioxidant activity and inhibitory effects of B. pilosa flower and leaf extracts on albumin denaturation, α-glucosidase, α-amylase, xanthine oxidase, and tyrosinase. The choice of extractants (water, methanol, acetone, and ethyl acetate) greatly influenced the phenolic content and bioactivities of the extracts. The results demonstrated the flower and leaf extracts differed significantly with respect to total phenolic content and abilities to inhibit albumin denaturation, α-amylase, and xanthine oxidase. The ethyl acetate extracts may show the strongest activity to scavenge DPPH radicals, to inhibit α-amylase and α-glucosidase, and to protect albumin against denaturation. The aqueous extract possessed the strongest capacity to inhibit xanthine oxidase while the acetonic extract was more effective in suppressing tyrosinase compared to the others.