ANTIBACTERIAL ACTIVITY OF AQUEOUS AND ETHANOL EXTRACT OF TEN DIFFERENT COMMERCIAL SPICES AND HERBS AGAINST THREE CLINICAL BACTERIAL ISOLATES

Abstract

The use of spices in the treatment of diseases has not been fully exploited. Ethanol and aqueous extract of the following spices: Garlic (Alium sativum), Onion (Allium cepa), Cinnamon (Cinnamomum verum), Thyme (Thymus vulgaries), Ginger (Zingiber officinale), Lime leaf (Citrus aurantifolia), Curry (Murraya koenigii), Bay leaf (Laurus nobilis), Red pepper (Capsicum annum L.) and Tumeric (Curcuma longa) were tested for their antibacterial activity against Staphylococcus aureus, Escherichia coli and Klebsiella pneumoniae, using agar well diffusion method at concentrations of 100, 75, 50 and 25mg/mL. The Minimum Inhibitory Concentration (MIC), synergistic effect of two spices in the same family and antimicrobial sensitivity were also determined. Aqueous and ethanol extract of cinnamon were the most effective against the test organism with zones of inhibition between 9mm to 25mm; closely followed by tumeric which also showed good inhibitory effect on the test organisms except that the aqueous and ethanol extract did not have any effect on E. coli and S. aureus respectively. Garlic–onion aqueous extract inhibited the test organisms with zones of inhibition ranging between 9mm to 24mm. Ginger - tumeric aqueous extract did not have any effect on E. coli and S. aureus. The MIC for aqueous and ethanol extract of cinnamon was 3.125mg/ml and 12.5mg/ml respectively. E. coli was highly susceptible to gentamicin than the remaining two organisms. This work has shown that both cinnamon and turmeric can be used as antimicrobial agents in the treatment of some diseases.