Abstract

• One of Myanmar's medicinal plant, Dalbergia cultrata Graham Ex Benth. was selected for chemical investigation and partial structure elucidation. Firstly, the phytochemical screening of the stem bark of D. cultrata was performed by standard method, indicating the presence of α amino acids, carbohydrates, flavonoids, glycosides, phenolic compounds, reducing sugars, saponins, tannins, steroids and terpenoids. In addition, the OECD Guidelines of Limit Test (425) examined the acute oral toxicity test to determine a test sample's median lethal dose (LD50). Based on the result, a 2000 mg/kg ethanol extract dose showed no signs of acute toxicity in all the experimental mice. However, one animal died at a dose of 5000 mg/kg, indicating that this dosage is approaching or surpassing the LD50 threshold. The administration of 2000 mg/kg ethanol extract to the test animals showed the results of normal to significant weight gain in all the animals. However, at 5000 mg/kg, animal 3 showed considerable weight loss, which showed that the dose may have caused adverse effects in some individuals. The Agar well diffusion method evaluated the antimicrobial activity of n-hexane, dichloromethane, ethyl acetate, watery, and ethanol extracts. It was found that ethanol and ethyl acetate extracts showed high activity on all organisms except Bacillus substilis and Escherichia coli. The antioxidant activity of ethyl acetate and ethanol extracts was evaluated using the DPPH assay method. It was found that ethyl acetate extract showed higher antioxidant activity than ethanol extract.