Abstract

• This study investigated the antimicrobial, antioxidant, cytotoxic, and anti-arthritic activities of Crateva magna (LOUR.) DC. (Kadet) leaf. Preliminary phytochemical screening confirmed the presence of alkaloids, α-amino acids, carbohydrates, glycosides, organic acids, phenolic compounds, reducing sugars, saponins, starch, steroids, tannins, terpenoids, and flavonoids, while cyanogenic glycosides were not detected. The antimicrobial activity of aqueous, ethanol, ethyl acetate, and petroleum ether extracts was evaluated using the agar well diffusion method. Ethanol and ethyl acetate extracts demonstrated strong antimicrobial activity, with inhibition zones measuring 25 to 26 mm. In antioxidant activity accessed via the DPPH free radical scavenging assay, the water extract had an IC50 of 345.58 μg/mL, while the ethanol extract showed a significantly lower IC50 of 24.81 μg/mL. Cytotoxicity was tested using the brine shrimp lethality bioassay, indicating both extracts were non-toxic at a concentration of 1000 μg/mL, with LC50 values suggesting safety. Anti-arthritic activity was evaluated using the egg albumin denaturation method, revealing that the water extract (IC50 = 66.26 μg/mL) had stronger anti-arthritic effects than the ethanol extract (IC50 = 68.39 μg/mL).