Abstract

• Picrasma javanica Bl. (Nann-paw-kyawt) bark is one of the well known traditional medicinal plants. Since it has an invaluable medicine purpose, the bark of P. javanica was chosen for this research work. This study was designed to examine the phytochemicals, mineral contents, antioxidant activity and total phenol contents of P. javanica bark. In the present work, the preliminary phytochemical tests revealed that alkaloids, α-amino acids, carbohydrates, flavonoids, glycosides, phenolic compounds, reducing sugars, saponins, starch, steroids, tannins, terpenoids and organic acids were present and cyanogenic glycosides were not found in P. javanica bark. The mineral contents (Ca, K, Si, Fe, S, Mn, Ti, Zn, Cu, Sr and Rb) of P. javanica bark powder sample were determined by EDXRF. Among them, the calcium content of this sample was the highest (66.904 %). A compound Des-4-methyl-19-hydroxyquassin (0.013 %, white solid) was isolated from chloroform extract of P. javanica bark. In vitro antioxidant activities of ethanol and watery extracts of P. javanica bark were also assessed by 2, 2 diphenyl-1-picrylhydrazyl (DPPH) and Nitric Oxide free radical scavenging (NO) assays. By using DPPH assay the IC50 values of ethanol and watery extracts of P. javanica bark were 23.28 μg/mL and 17.47 μg/mL respectively. And also IC50 values of ethanol and watery extracts of P. javanica bark were 271.80 μg/mL and 105.28 μg/mL by using nitric oxide assay. The total phenol contents were determined by Folin-Ciocalteu Reagent (FCR) method and watery extract (19.67 μg GAE/mg) was found to be higher than ethanol extract (18.97 μg GAE/mg).