Abstract

• Citrus hystrix DC. (Shout-nu) used in household remedy for medicinal purposes was chosen for present study. Gastrointestinal tract problems and some diseases caused by mosquito become challenges in Myanmar people that many researchers have revealed the finding results of therapeutic properties from natural sources. The aim of this study is to analyze essential oil extracted from Citrus hystrix leaf Essential oil (0.02 g, 0.04 %) was extracted from leaf sample by hydro distillation method and was analysed by Fourier transform infrared (FT IR) spectroscopy. The chemical composition with molecular mass in essential oil was then determined by gas chromatography-mass spectrometry (GC-MS). Eight compounds of terpenes: alpha-pinene, D-limonene, beta-ocimene, gamma-terpinene, isopulegol, citronellol, caryophyllene and beta-bisabolene were detected. By solvent extraction method, four crude extracts of Citrus hystrix leaf were prepared with various solvents: petroleum ether, ethyl acetate, 96 % ethanol and water. Antimicrobial activity of four crude extracts was investigated against ten microorganisms by paper disc diffusion method. It was found that all tested leaf extracts exhibited ten tested microorganisms with the inhibition zone diameters range between 9~27 mm. Nevertheless, acute toxicity of 96 % EtOH and water extracts from Citrus hystrix leaf was evaluated by the method of (OECD) guidelines 423 that all tested Citrus hystrix leaf sample showed no toxicity. In addition, larvicidal activity of PE, EtOAc, water extracts and essential oil was studied by WHO standard method. According to larvicidal activity test, PE extract and essential oil have the highest larvicidal activity in vivo test larvae model, 3rd and 4th instar Aedes larvae. This research can support to the formulation of antimicrobial drugs and can provide on alternative source of mosquito control agents.