Antioxidant and Antidiabetic Activities of Mempening (Lithocarpus bancanus) Leaves

Background: Lithocarpus bancanus or commonly called as mempening in Talang Mamak Tribe, Indonesia is a plant that is used as a traditional medicine. Objective: This study aim to evaluated antioxidant and antidiabetic activities of L. bancanus leaves extract. Material and Methods: The methanol extract was obtained by maceration of the leaves. The n-hexane, dichloromethane and ethyl acetate fractions were prepared by successive partition process of the methanol extract. Antioxidant activities were evaluated by various antioxidant assays, including DPPH (1,1-diphenyl-2-picrylhydrazyl), FRAP (ferric reducing antioxidant power), CUPRAC (cupric reducing antioxidant capacity), and ABTS (2,2’-azonobis 3-ethylbenzothiazoline-6-sulfonic acid) method. Total phenolics were estimated based on the Folin–Ciocalteu method, while, aluminum chloride methods were employed to estimate total flavonoids. Antidiabetic activies was determined by inhibiting the activity of α-glucosidase method. Results: antioxidant activity assay against DPPH radical as well as the total phenolic and flavonoid content of L. bancanus leaves showed that the methanol extract possessed IC₅₀ value of 39.469 ± 0.273 μg/mL with total phenol and flavonoid were 11.426 ± 0.432 mg GAE/g dry weight sample and 15.423 ± 0.213 mg QE/g respectively. The FRAP, CUPRAC and ABTS values of methanol extract were 3494.302 ±0.456, 26665.501 ± 5.940 and 2857.977 ± 0.715 μM TE/g dry weight sample respectively. Antidiabetic activity of methanol extract with IC₅₀ value of 30.565 ± 0.331 μg/mL. Conclusion: It could be concluded that leaves of L. bancanus have antioxidant and antidiabetic properties.