A study into the antimicrobial effects of cloves (Syzgium aromaticum) and cinnamon (Cinnamomum zeylanicum) using disc‐diffusion assay

Abstract

Purpose -This paper is aimed at food science or biology students planning a practical independent study into the antimicrobial properties of spices and academic staff wishing to develop a straightforward and reproducible practical activity. Design/methodology/approach -Disc-diffusion assays are used to investigate the antimicrobial activity of cinnamon and cloves against two bacteria Escherichia coli B and staphylococcus albus and a yeast Saccharomyces cerevisiae. Aqueous and alcoholic extracts of the spices and alcoholic extracts of their essential oils are examined. Minimum inhibitory concentrations of alcoholic extracts of both spices and oils are also determined. Findings -Both spices demonstrated microbial inhibitory effects; alcoholic extracts had greater activity than aqueous extracts. Additionally, essential oils had greater activity than the spices. Minimum inhibitory concentrations were smaller with the oils than with the spices. Research limitations/implications -Although the research for this paper involved just two spices, such is the size of the plant kingdom that there are wide opportunities for further investigations using this procedure. Practical implications -Disc-assays were found to be a simple, cheap and reproducible practical method. For this paper, micro-organisms available for educational purposes were used; however, other organisms could be investigated depending upon available microbiological expertise and facilities. Originality/value -The results demonstrate that the antimicrobial effects of spices and particularly their essential oils can be examined using disc-diffusion assay. The method provides many opportunities for student investigation.

Antimicrobial potential of the Ethiopian Thymus schimperi essential oil in comparison with others against certain fungal and bacterial species

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“…However, the present study results were better than reported by (Gulay-Kirbasilar et al ., [ 15 ]). This may be due to variations in climate and soil composition in which the plant growing [ 12 , 13 ].…”

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Antibacterial activity of extracts of diploid and induced autotetraploid Tunisian populations of Trigonella foenum-graecum L.

“…In vitro antibacterial activities of T. foenum-graecum extracts were determined by the agar disk diffusion method according to Ghalem and Mohamed (2009). Disk assays were found to be a simple, cheap and reproducible practical method (Maidment et al, 2006). The inocula grown in the nutrient broth at 37ºC for 24 h were diluted to approximately 10 6 CFU/ml in nutrient broth.…”

Chinese herb-resistance and adherence to human uroepithelial cells of uropathogenic <i>Escherichia Coli</i>

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