Abstract: The objective of this study was to evaluate the antidiabetic potential of Garcinia Xanthochymus in vitro.The α-glucosidase and α-amylase inhibitory activities of the petroleum ether(PFr.),ethyl acetate(EFr.),n-butanol(BFr.) and water fractions(WFr.) of the root,leaf and fruit of G.Xanthochymus were assessed.Glucose consumption was evaluated using HepG2 cells.Fruit-EFr(IC₅₀=17.81 ± 1.09 μg/mL),leaf-EFr(IC₅₀=18.60 ± 1.56 μg/mL),root-EFr(IC₅₀=14.05 ± 0.24 μg/mL) and root-BFr(IC₅₀=13.01 ± 0.38 μg/mL) showed higher α-glucosidase inhibitory activity than acarbose(IC₅₀> 200 μg/mL).The root EFr and BFr showed the highest α-glucosidase inhibitory activity among all samples(ca.90%,at a concentration of 600 μg/mL).The α-amylase inhibitory activity rate of the root EFr and BFr reached 90% at a concentration of 1.5 mg/mL.In glucose consumption assay,four fractions were efficient on promoting glucose consumption activity.The fruitEFr at a concentration of 7.5-30 mg/mL significantly promoted glucose consumption(P< 0.001) and the glucose consumption rates of cells treated with leaf-EFr,root-BFr and root-EFr were 3.08,3.12 and 1.93,respectively,slightly lower than the glucose consumption rate of cells treated with fruitEFr.These findings supported the antidiabetic claims of G.xanthochymus in vitro.

Key words: Garcinia xanthochymus, antidiabetic activity, &alpha, -glucosidase inhibitory activity, &alpha, -amylase inhibitory activity, HepG2 cells glucose consumption assay