Antioxidant and α-glucosidase inhibitory activities of compound isolated from Stachytarpheta jamaicensis (L) Vahl. leaves

Stachytarpheta jamaicensis is one of the folk medicines used for the treatment of diabetes in Ambon, Indonesia, but there are limited studies on the bioactivities of its constituents. This study aims to assess the antioxidant and antidiabetic activities of four extracts of S. jamaicensis leaves extracted using several solvents. Bioassay guided fractionation on each extract establishes for exploring S. jamaicensis leaves active compounds. The antioxidant was evaluated using the DPPH and ABTS methods, while the α-glucosidase inhibitory was carried out in vitro assay. The results showed that the methanol extract of S. jamaicensis leaves displays inhibition of DPPH, ABTS and α-glucosidase activity compared to other solvent extracts. Furthermore, 6β-hydroxyipolamiide was successfully isolated from the methanol extract of S. jamicensis leaves which was reported to have α-glucosidase inhibitory activity with an IC₅₀ of 539.17 μg/mL. Based on the results, S. jamaicensis could be recommended as an antioxidant and antidiabetic agent.