ANTIBACTERIAL ACTIVITY OF OCIMUM GRATISSIMUM EXTRACT ON MULTIDRUG RESISTANT KLEBSIELLA PNEUMONIAE AND STAPHYLOCOCCUS AUREUS

Abstract

This study was conducted to investigate the multidrug resistance pattern in Klebsiella pneumoniae and Staphylococcus aureus in clinical (urine and post operative wound) and environmental (market soil, well water and hospital air) sources in Ondo State and the possibility of treating infections caused by resistant strains of K. pneumoniae and S. aureus with extract of Ocimum gratissimum (scent leaf). A total of 690 sources are sampled. The organisms were isolated using microbiological standard techniques. The bacterial loads of samples from Ondo North, South and Central ranged from 4.65 to 6.17 log10 cfu/ml, 4.78 to 6.20 log10cfu/ml and 4.36 to 6.21 log10cfu/ml respectively. The highest total bacterial count of S. aureus was observed in Ondo north and central while the highest bacterial counts of K. pneumoniae was observed in Ondo central. Bacterial load of S. aureus in post operative wound was significantly (p≤0.05) higher than other sources except in Ondo south that the S. aureus was found to be higher in market soil, while the bacterial load of K. pneumoniae was significantly (p≤0.05) higher in market well water. Most of the clinical and environmental isolates were more resistant to most of the antibiotics used except K. pneumoniae isolated from urine sample which had no significant difference (p≤0.05) in susceptibility pattern to all antibiotics used. High resistance of K. pneumoniae and S. aureus to multiple antibiotics was observed in Ondo north and south. There was significant difference (p≤0.05) in the percentage resistance between the clinical and environmental isolates. It was also observed that clinical and environmental isolates showed least resistance to ofloxacin, pefloxacin and ciprofloxacin. The bacterial isolates that were resistance to two or more antibiotics were subjected to plasmid profiling and curing. The antibacterial activity of O. gratissimum extracts exhibited some antimicrobial activity on the multidrug resistant K. pneumoniae and S. aureus at different concentrations used but it was more active at 200 mg/ml. The preliminary investigation of the phytochemical constituents of the leaf extract of O. gratissimum revealed the presence of some active metabolites such as tannins, flavonoids, saponins, steroids, alkaloids, phlobatannins, glycoside and terpenoids. This is an indication that the plant had a strong antimicrobial effect on the test K. pneumoniae and S. aureus. In comparison, the ethanol extract had the highest level of antimicrobial activity than n-hexane and water extract. The study reveals that the plant is of therapeutic potential due to the present of phytochemicals in the leaves. Therefore, this finding proved the potentiality of the plant extract for treatment of infections in herbal medicine.