Nine compounds including a new one, garcichaudiic acid (1), were isolated from the bark of G. gaudichaudii and their structures were characterized mainly by 1 D and 2 D NMR experiments. The antioxidant capacity of the isolated compounds was determined using DPPH radical scavenging assay and the anti-hyperglycemic activity was assessed by measuring the inhibitory effect against α-glucosidase. Among them, compound 4 showed higher antioxidant activity than the positive control, ascorbic acid, while both compounds 1 and 7 exhibited more significant α-glucosidase inhibitory activity than the reference drug acarbose. Molecular docking analysis of the bioactive compounds was also performed to examine the binding modes and key interactions with the catalytic site.
Keywords: Diabetes; Garcinia gaudichaudii; antioxidant; garcichaudiic acid; α-glucosidase.