Evaluation of antimicrobial activity of ginger and garlic extracts against isolates of Staphylococcus aureus, Escherichia coli and Salmonella species

Abstract

Microorganisms are very ubiquitous and they surround man whereas some live inside man among which are the normal flora. Different conditions have made them opportunistic pathogens of virulence and there is continuous drug resistance in these microorganisms. This has threatened human health forcing Researchers to come up with solutions like; making use of plant alkanoids and spices. In this study, garlic (Allium sativum) and ginger (Zingiber officinale) extracts were used against isolates of Staphylococcus aureus, Escherichia coli and Salmonella species in Micro Biol. laboratory of Mulago Hospital in Kampala district. Susceptibility tests were done by agar well diffusion for each organism to the spices, compared with these microbes’ sensitivity to antibiotics ATCC-25923 (Oxacillin, Cefoxacillin, Gentamycin, Ciproflaxin, Vancomycin and Erythromycin), a standard control for Staph aureus and ATCC-25922 (Nalidoxil, Cefazadine, Impicillin and Cotrimoxazole) for E. coli and Salmonella species. Ginger had no activity against the microorganisms. Staphylococcus aureus was the most susceptible organism (44.5±0.5) mm in 100 μl garlic> (25.33±0.83) mm of ATCC-25923, followed by Salmonella species (32.1±0.5) mm in 100 μl garlic> (27.20±1.43) mm of ATCC-25922 but E. coli was the most resistant with (24.0±0.5) in 100 μl garlic< (27.20±1.43) mm in ATCC-25922. Further dilution or combining the extracts reduces an activity of garlic. In this study, the antimicrobial activity by garlic observed maybe attributed to the phytochemical contents like allicin which have previously been reported to have an antimicrobial activity. Further studies can be done to explore these properties in garlic.