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.

Citation

Maidment, C., Dyson, A. and Haysom, I. (2006), "A study into the antimicrobial effects of cloves (Syzgium aromaticum) and cinnamon (Cinnamomum zeylanicum) using disc‐diffusion assay", Nutrition & Food Science, Vol. 36 No. 4, pp. 225-230. https://doi.org/10.1108/00346650610676794