In vitro Antimicrobial Activity of the Flower Buds of Eugenia caryophyllata

Aims: This study investigated the antimicrobial effect of aqueous and ethanol extracts of the flower buds of Eugenia caryophyllata (Myrtaeae) against a wide range of bacteria and yeasts cells isolated clinically from patients.

Methodology: The agar diffusion method was used to establish the antimicrobial activity and the zones of inhibition caused by the extracts. The antimicrobial effects of 16% and 32% aqueous and ethanol extracts of Eugenia caryophyllata were investigated against 111 pathogenic bacteria and yeasts cells. The microbes used consisted of 11 Proteus mirabilis, 20 Salmonella typhi, 15 Pseudomonas aeruginosa, 18 Escherichia coli, 19 Staphylococcus aureus, 12 Klebsiella pneumoniae, and 16 Candida albicans species.

Results: The ethanol extracts inhibited the growth of all the microbes employed in the study with inhibition zones ranging from 8.00±0.00 mm to 24.00±0.00 mm. The aqueous extracts however exhibited different degrees of antimicrobial activity with zones of inhibition ranging from 6.00±0.00 mm to 13.33±0.29 mm.

Conclusion: Our study concludes that the aqueous and ethanol extracts of the flower buds of Eugenia caryophyllata have relatively good antimicrobial activity against a wide range of medically important pathogenic bacteria and Candida albicans in vitro.