Antimicrobial Activity and Phytochemical Screening of Neem Leaves and Lemon Grass Essential Oil Extracts

Abstract

In this study, the antimicrobial activity and phytochemical constituents of neem leaves and lemon grass oil extracts were evaluated. Oil extracts of neem leaves and lemon grass were obtained by solvent extraction method using hexane and ethanol. Antimicrobial activity screening of plants’ oil extracts were conducted using agar well diffusion method and the oil extracts were tested against three gram negative bacteria (Pseudomonas aeruginosa, Klebsiella specie, Escherichia coli), one gram positive bacteria (Staphylococcus aureus) and two fungi (Candida albicans, Rhizopus specie). Phytochemical components of the ethanolic oil extracts were anthocyanin and betacyanin; quinones; terpenoids and acid for lemon grass. In addition to other phytochemicals present in lemon grass ethanolic oil extract, neem ethanolic oil extracts tested positive to flavonoids. Lemon grass oil extract shows high activity against Escherichia coli, Staphylococcus aureus and Candida albicans which are representative of the three categories of microorganisms considered. Neem leaves oil extracts have relatively low activity against most of the selected microorganisms.

Keywords: microbial resistance, lemon grass extract, neem leave extract, bioactive compounds, susceptibility mechanism