THE PREDICTION OF ANTIBACTERIAL AND PHYTOCONSTITUENT ACTIVITIES OF METHANOLIC EXTRACT OF MANGIFERA INDICA AGAINST SELECTED CLINICAL ISOLATES

Abstract

There have been reports of increasing development of drug resistance among human pathogens as well as undesirable side effects of certain antimicrobial agents. It is therefore necessary to search for new agents that are better, cheaper and without side effects for treating infectious diseases especially in developing countries. In this study, phytochemical composition and antimicrobial activities of methanolic extracts of leaves and bark of Mangifera indica were investigated. Standard methods were employed to screen for the phytochemicals. Disk diffusion method was used to determine the antimicrobial effects of methanolic extracts of M. indica leaves against four different clinical isolates namely: Staphylococcus aureus, Escherichia coli, Pseudomonas aureginosa and Salmonella typhi which S. aureus has the highest zone of inhibition (20mm) while S. typhi has no zone of inhibition in leave while in bark, P. aureginosa has the highest (20mm) and S. typhi has the lowest zone of inhibition (10mm) and were compared with standard antibiotics which also high zones of inhibition. Quantitative and qualitative analysis of phytochemical constituents using the Gas Chromatography Mass Spectrophotometry (GC/MS) shows the presence of The active compounds with their retention time (RT), percentage abundant (%) and peak area (%). For the methanolic leave extract a total of eleven compounds were detected comprising of five prominent compounds and six minor constituents. The five prominent compounds asnd their percentage abundance are Diethyl Phthalate, 2-Acetylbenzoic acid, (3-Nitrophenyl)-3-oxopropanenitr (19.21%), Benzoic acid, 4-formyl (12.65%), Cyclohexene, 4-(4-ethylcyclohexyl), 1-pentyl (7.93%), Oxirane (6.51%) and 2,5-Furandione, 3-dodecyl- Oxirane, tridecyl-9,12-Octadecadien-1-ol, (Z,Z)-(5.11%). For the methanolic bark extracts a total of fifty-four compounds were detected comprising of ten prominent compounds and forty-four minor constituents.The ten prominent compounds and percentage abundance are Benzene-1,2-dicarboxylic acid, monoamide,N-(1-cyano-1-methylethyl)- (8.17%), 2-Acetylbenzoic acid bis1-methylethyl), ester (6.67%), 4-Pyrimidinamine, 5-(2-thienyl)-, Methoxy-6-nitro-2H-1,3-benzodioxole-5-carbonitrile (E)-2-((But-2-enyloxy)carbonyl) (5.40%), Benzoic acid, 4-formyl2-, Acetylbenzoic acid (5.12%), Phenol, 2-ethoxy-4-(2-propenyl)- (4.94%), Aspidospermidin-17-ol, 1-acetyl-19,21-epoxy-15,16-dimethoxy,Tetradecanal (4.12%), Butyl 9-octadecenoate or 9-18:1, Cyclotetradecane, 9-Oxabicyclo[6.1.0]nonane, cis-(4.11%), Oxirane, tridecyl-, Erucic acid (3.87%), Cycloeicosane, 1-Docosene (3.47%) and 1-Hexacosene (3.15%).The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the extract was done using broth dilution.