Abstract

• The study aims to investigate some biological activities and the isolation of phytoconstituents from the leaves of Dregea volubilis (L. f.). Dregea volubilis belongs to the Apocynaceae family, and it is locally known as “Gway-tauk” in Myanmar. In our experiments, six compounds (1-6) were isolated from the EtOAc extract of Gway-tauk leaves, and they were characterized by some physico-chemical tests, Rf values on TLC, and modern spectroscopic methods such as UV and FT IR. The antimicrobial activity of EtOH extract showed moderate activity with the inhibition zone diameter range between 10~15 mm against eight tested microorganisms. Then, EtOH and watery extracts were found to have no cytotoxic effect on brine shrimp up to the maximum dose of 1000 µg/mL. Moreover, the watery extract (bitterness value, 320) of Gway-tauk leaves was less bitter than standard quinine hydrochloride R (bitterness value, 2000). In the α-amylase inhibitory activity, the IC50 values of ethanol and watery extracts were observed to be 3.64 and 2.67 µg/mL. The antioxidant activity of ethanol (IC50: 3.54 µg/mL) and watery (IC50: 5.11 µg/mL) extracts of Gway-tauk leaves possessed potent antioxidant activity, as well as positive control ascorbic acid (IC50: 2.60 µg/mL).