Abstract

• In this research, the roots of Diospyros ehretioides from Tetma Village, Nyaung U Township, Mandalay Region were selected to investigate some chemical constituents and some biological activities such as acute toxicity and antimicrobial activities. Four known lupane triterpenoids, lupeol, betulin, betulinaldehyde, and betulinic acid were isolated from the roots of Diospyros ehretioides by column chromatography. The structures of these isolated compounds were identified by extensive spectroscopic analyses such as UV, IR, 1H and 13C NMR, DQF-COSY, HMQC, and HMBC spectra and comparison with the literature data. The acute toxicity of the ethanol extract of the roots evaluated by Organization for Economic Cooperation and Development (OECD) 425 guideline revealed no toxic effects and lethality at a dose of 5000 mg/kg (LD50>5000 mg/kg). Moreover, the antimicrobial activity of crude extracts (ethanol, DCM and hexane) of Diospyros ehretioides root was evaluated against five pathogenic microorganisms by agar well diffusion method. Except for E. faecalis, all crude root extracts inhibited four microorganisms, with the inhibition zone diameters ranging from 10 to 15 mm, respectively.