Pharmacotherapeutic Activity of Allium sativum (Garlic) Bulb against Gram-positive and Gram-negative Bacteria

Background: Emergence of methicillin drug resistance is evident and has become a global challenge. Seeking for alternative antibiotics that are new, natural, plant based, cost effective and less toxic is the recent task for global health.

Aim: This study is aimed at assessing the pharmacotherapeutic activity of Allium sativum (Garlic) bulb against gram-positive and gram-negative bacteria.

Materials and Methods: Fresh A. sativum bulbs were purchased from a local market in Ibadan, Nigeria and were identified by a botanist. They were cut into small pieces and mashed in a laboratory with a mortar and pestle and the fluid squeezed out of the resultant slurry. The antibacterial activity of the juice was determined by diffusion method. Nutrient agar medium was prepared using standard method. Pure cultures of Coliform bacillus, Staphylococcus epidermidis, Streptococcus viridians, Salmonella typhi and Escherichia coli were obtained from the Department of Veterinary Microbiology and Parasitology, Federal University of Agriculture, Abeokuta, Nigeria. The juices 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 juice 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 A. sativum bulb has antibacterial potential against all the bacteria used in this study and also exhibited inhibitory activity against them.

Conclusion: The result of this present study showed that A. sativum juice has high range of antibacterial potential against both gram positive (S. epidemidis and S. viridans) and gram negative bacteria (C. bacillus, E. coli and S. typhi). However, the extract has a greater inhibitory activity against gram positive bacteria than gram negative bacteria.