Inhibitory effect of Syzygium aromaticum L. and Coffea arabica L. extract on Staphylococcus aureus in vitro and comparing it with selected antibiotics

Abstract

Since antimicrobial resistance is on the rise, especially in vital microscopic organisms responsible for nosocomial contaminations, finding effective and safe anti-bacterial compounds is one of the most significant research areas. As an important bacterial pathogen, Staphylococcus aureus is considered one of the leading causes of nosocomial infections. In this study, based on the antimicrobial properties of medicinal plants, the inhibitory and anti-bacterial effects of aqueous extracts of Syzygium aromaticum L. and Coffea arabica L. on S. aureus bacteria were investigated by disk diffusion test. Aqueous extraction was executed, and the inhibitory effect of these plants was examined in the Muller-Hinton agar medium. The results were measured by a caliper. According to the results, clove and coffee aqueous extracts appear effective at creating a zone of inhibition against S. aureus. By increasing the concentration of the extract, larger zone of inhibitions, as large as selected antibiotics, are formed against the growth of S. aureus. Clove aqueous extract at a concentration of 100 μl exhibited a zone of inhibition of 30 mm. In contrast, coffee extract at the same concentration exhibited a zone of inhibition of 23 mm. Furthermore, the inhibition zones created by the selected antibiotics, tetracycline and vancomycin, were found to be 24 mm and 27 mm, respectively. As a final result, clove and coffee aqueous extracts have a significant antimicrobial effect on S. aureus.