Antibacterial Activity and Identification of Bioactive Compounds in Extracts of Garlic cloves and Lemon juice by GC-MS Analysis

Abstract

The search for alternative regimens to treatment of infectious diseases as well as the increase in antibiotic resistance by pathogens has prompted continuous efforts towards discovery of new drugs. In this study, crude aqueous and acetone extracts of garlic cloves and lemon juice were obtained. The extracts were tested against clinical isolates of Staphylococcus aureus. The antibacterial activity was determined by agar well diffusion method on Mueller-Hinton Agar plates. All extracts showed inhibitory action against the bacterium with acetone extracts having higher activity than the aqueous extracts. The acetone extracts were further fractionated using solvent – solvent extraction and retested on the bacterium. The bioactive compounds that lead to the antibacterial activity of the fractions of the extracts were identified by Gas Chromatography-Mass Spectrometry analysis where 2,5-Furandione and dihydro-3-methylene were identified in garlic cloves fraction as main compounds with other 8 compounds in trace quantity while 11-Octadecenoic acid methyl ester, Oleic acid and n-Hexadecanoic acid were identified in lemon juice fraction as main compounds with 6 other compounds in trace quantity. These findings claim capacity and future use of these compounds for new drug development. The future work will be to determine toxicity, side effects and pharmaco-kinetic properties of the compounds.

Keywords: Antibacterial activity, Garlic cloves, Lemon juice, GC-MS analysis, bioactive compounds.