ABSTRACT

Medicinal plants are of great importance to the health of individual and the communities. The medicinal value of some plants lies in some chemical substances that produce definite physiological actions in the human body. The aim of this study is to determine the  susceptibilities of bacteria pathogens to antibiotics and extracts of Ocimum gratissimum. Fresh leaves of Ocimum gratissimum were collected from Ubani main market in Umuahia, Abia state and was transported to the laboratory for microbiological analysis Stock cultures of the bacterial isolates were collected from Research Institute Microbiology Laboratory Unit, Umuahia, Abia State, Nigeria. The isolates were subjected to Gram staining and other biochemical tests according to standard procedures and identified as Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Klebsiella sp.  After microbial analysis, different concentrations of water extract of the Ocimum gratissimum used were 25mg/ml, 20mg/ml, 15mg/m 10mg/ml and 5mg/ml. But none of the concentration inhibited any of the test organisms while ethanolic extracts used were 25mg/ml, 20mg/ml, 15mg/ml, 10mg/ml and 5mg/ml. 25mg/ml, inhibited all the 4 isolates, while 20mg/ml and 15mg/ml  inhibited E. coli, Pseudomonas aerugonosa and Klebsiella species. The MIC on S. aureus is 25mg/ml, on E. coli is 15mg/ml, on Pseudomonas aeruginosa is 15mg/ml and Klebsiella species is 15mg/ml. The different control drugs used were Ciprofloxacin, Gentamycin, Streptomycin, Amoxil and Erythromycin. Ciprofloxacin, gentamycin and streptomycin, inhibited all the isolates. Amoxil inhibited all the isolates except S. aureus while erythromycin did not inhibit any of the isolates. This study justifies the use of the leaves in traditional medicine practice as a therapeutic agent and can explain the long history use of these plants. This research work has shown that Ocimum gratissimum has potential antibacterial components that are responsible for its antibacterial activities.