Abstract

• Chemical constituents of Melicope ptelefolia (Thit-Kha) leaf and some pharmacological properties were investigated. The preliminary phytochemical test was determined by test tube method. Dried leaf sample was found to consist of 6.39 % of moisture, 7.64 % of ash, 21.94 % of protein, 14.92 % of dietary fiber, 3.93 % of crude fat, 45.18 % of carbohydrate, and 303 kcal/100g of energy value, respectively. According to the EDXRF spectrum, the samples had relatively high Si, K and Ca. Total phenol and total flavonoid contents of M. ptelefolia (Thit-Kha) leaf by using Folin- Ciocalteu reagent (FCR) method and by using spectroscopic method. According to the observed data, total phenol content was very high in watery extract (273.78 μg GAE/mg) followed by ethanol extract (119.87 μg GAE/mg) and methanol extract (103.84 μg GAE/mg). In addition, the total flavonoid was also very high in watery extract (79.24 μg QE/mg) followed by ethanol extract (78.81 μg QE/mg) and methanol extract (60.09 μg QE/mg). The antioxidant activity of watery extract (IC50 = 15.44 µg/mL was found to be higher than those of ethanol extract (IC50 = 59.62 µg/mL) and methanol extract (IC50 = 45.79 µg/mL) determined by DPPH radical scavenging assay. Antimicrobial activity was also determined by agar well diffusion method. Ethyl acetate and methanol extracts exhibited the highest antimicrobial activities. The cytotoxicity of methanol extract was studied by MTT assay method. From the results, the concentration of methanol extract increased, the cell viability also decreased.