Antimicrobial Activities and Cellular Toxicity of Ethanol and Methanol Extract of <i>Ocimum Gratissumum</i> from Enugu, South Eastern Nigeria

Abstract

Antimicrobial effects of ethanol and methanol extracts of Ocimum gratissimum from against three (3) bacteria -E. coli, Pseudomonas aeruginosa and Staphylococcus aureus isolated from urine; two (2) typed bacterial strains – E.coli (ATCC 117755) and S. aureus (ATCC 12600); and six (6) fungi isolates - Trichophyton rubrum, Microsporum gypseum, Aspergillus flavus, Penicillin specie, Candida albicans [skin] and Candida albicans [HVS]), respectively was investigated using agar well diffusion technique. Cellular toxicity testing was carried out using Human group O red cells. Lower MICs of both extracts were observed more effective against bacterial isolates; whereas fungi isolates were susceptible at higher MIC values. P. aeruginosa was the most susceptible bacteria with 10.0 and 9.3% inhibition ZID at MICs - 1.20 and 0.76 µg/ml for the ethanol and methanol extracts, respectively; while C. albicans (skin ) was the most susceptible fungi with 19.1 and 16.7% inhibition ZID at MICs -9.72 µg/ml (ethanol extract) and 6.16 µg/ml (methanol extract), respectively. Non-clinical fungi (Penicillin species and A. flavus) exhibited a higher susceptibility to both extract than the dermatophytes tested (T. rubrum and M. gypseum). Also, both extracts showed no observable lytic effect against Human group O red cell, suggesting safety of the oil either in part or whole, for potential consumption and in vivo clinical use.

Keywords: O. gratissimum; Antibacterial, Anti fungal, Cellular toxicity.

Nigerian Journal of Health and Biomedical Sciences Vol. 6 (2) 2007: pp. 33-38