Evaluation of antioxidant and anticancer activities of Orthosiphon aristatus (Blume)

Abstract

Orthosiphon aristatus (Blume) Miq. (Lamiaceae) is traditionally used to treat various ailments like diabetes mellitus, hypertension, rheumatism, tonsillitis, menstrual disorders and those affecting the urinary tract. The current study was aimed at phytochemical analysis and the evaluation of antioxidant and anticancer activities of methanolic extract of O. aristatus. In vitro antioxidant activity was performed by different methods such as phospho- molybdate assay, ferric reducing power, 1,1-Diphenyl-2-picryl-hydrazyl (DPPH), superoxide scavenging assay. Cytotoxic activity against Ehrlich Ascites Carcinoma (EAC), colon carcinoma (HT-29) and breast adenocarcinoma (MCF- 7) cell lines was evaluated by MTT assay. The plant exhibited significant antioxidant activity. In phosphomolybdate assay, O. aristatus (IC ₅₀ = 0.11mg/mL) showed higher antioxidant activity than the standard, ferrulic acid (IC ₅₀ = 0.22 mg/mL). The extract showed better anticancer activity against EAC (IC ₅₀ = 1.02mg/mL), and HT-29 cell lines (IC ₅₀ = 1.09mg/mL) compared to MCF-7 cell lines (IC ₅₀ = 21.25mg/mL). The extract showed promising radical scavenging activity that is comparable to standard. However, the results showed lesser anticancer activity for the extract compared to the standard. Further in vivo studies are required to evaluate the effect of biological factors on the efficacy of the extract.