Title:
Therapeutic Effect of Ethanolic and Aqueous Extracts of Ocimum Gratissimum Leaves Against Gram-positive and Gram-negative Bacteria

Authors:
A. I. Airaodion*, A. U. Megwas, J. A. Ekenjoku, K. O. Ngwogu, A. C. Ngwogu, Nigeria

Abstract:

Aim: This study is aimed at evaluating the therapeutic effect ethanolic and aqueous extracts of Ocimum gratissimum Leaves against gram-positive and gram-negative bacteria.

Materials and Methods: Fresh and healthy leaves of O. gratissimum were harvested, air dried and milled into powder and extracted using ethanol and water as solvents. The antibacterial activities of both extracts were determined by diffusion method. Nutrient agar medium was prepared using standard method. Pure cultures of Coliform bacillus, Staphylococcus epidermidis, Streptococcus viridans, Salmonella typhi and Escherichia coli were obtained from the Department of Veterinary Microbiology and Parasitology, Federal University of Agriculture, Abeokuta, Nigeria. The extracts were serially diluted to obtain 1.0%, 0.5%, 0.25%, and 0.125% solutions in sterile test tubes. Sterilized 9 mm filter paper disc soaked in the diluted extracts were placed on the plate and incubated for 24 hours at room temperature. The plates were examined for clear zones of inhibition. Presence of zones of inhibition indicated activity.

Results: The results showed that both ethanolic and aqueous extracts of O. gratissimum leaves has antibacterial potential against all the test organisms used in this study and also exhibited inhibitory activity against them. However, the inhibitory activity of the ethanolic extract was greater than that of the aqueous extract.