IN-VITRO PRELIMINARY PHYTOCHEMICAL ANALYSIS AND PHARMACOLOGICAL SCREENING FOR ANTIOXIDANT AND ANTIDIABETIC POTENTIALS OF ORTHOSIPHON GLABRATUS BENTH LEAF IN DIFFERENT SOLVENT FRACTIONS

In an attempt to reveal the medicinal values of Orthosiphon glabratus Benth leaf, which claims to have traditional use for the management of diabetes. In-vitro antioxidant and antidiabetic potentials of Orthosiphon glabratus leaf in different solvent fractions were studied by utilizing DPPH, ABTS, and α-amylase, α-glucosidase inhibitory methods respectively. A preliminary phytochemical study shows the presence of important constituents such as alkaloids, flavonoids, phenols, cardiac glycosides and terpenoids in all the solvent fractions. The ethyl acetate fraction exhibits the best inhibition activity against DPPH and ABTS, and its IC₅₀ was found to be 2.28 and 1.68 µg/mL respectively, which is significantly lower (P<0.05) than reference. In case of antidiabetic activity, ethyl acetate fraction shows the highest enzyme inhibitory action against α-amylase and α-glucosidase and IC₅₀ value was found to be 2.09 and 4.66 µg/mL respectively than (P<0.05) acarbose. The results of in-vitro antioxidant and antidiabetic assays on different solvent fractions of Orthosiphon glabratus leaf, it is evident that the ethyl acetate fraction could be potential candidature, which possessing the majority of phytochemical classes of compounds and it could be the reason for its antioxidant and antidiabetic activities. However, further studies are necessary to isolate the bioactive principles in Orthosiphon glabratus leaves that are responsible for management of diabetic and as antioxidant.