Abstract

• The study aimed screening some phytochemical constituents of the leaf of Senna siamea (Lam.) Mezali, as well as some biological activities, including antioxidant, antimicrobial, and cytotoxic effects. It was widely used in traditional medicine to treat various complaints. The cytotoxic activity of the ethanol and water extracts was determined by a brine shrimp lethality bioassay. The ethanol extract was more cytotoxic than the water extract. The antioxidant activity of ethanol and water extracts of Senna siamea was determined by DPPH assay. These assays found that the ethanol extract (IC50 = 39.53 µg/mL) in antioxidant activity was more potent than the water extract (IC50 =69.93 µg/mL).The antimicrobial activity of four crude extracts (pet-ether, ethyl acetate, ethanol and water) was determined by the agar well diffusion method. The ethyl acetate extract was found to have higher potent antimicrobial activity than PE, EtOH and watery extracts. The findings suggest that the various extracts possess substantial potential for therapeutic application.