Antibacterial Activities of Three Spices on Some Human Bacterial Pathogens

Aim: The aim of this study was to determine the susceptibility pattern of bacterial pathogens against spice extracts.

Place of Study: Microbiology laboratory of Bells University of Technology; between August, 2015 to July, 2016.

Methodology: The three spices; Capsicum annuum (cayenne), Curcuma longa (turmeric) and Piper guineense (black pepper) were analyzed for the presence and absence of metabolites using standard methods and also tested for their activity against some clinical bacterial pathogens namely: Bacillus subtilis, Staphylococcus species, Escherichia coli, Enterobacter agglomerans, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Acinetobacter baumannii. Antibacterial testing was done using agar diffusion method on Mueller-Hinton agar plates following standard methods.

Results: This study demonstrated that the three spices contained alkaloids, tannins, saponins, flavonoids, steroids, and terpenoids. Piper guineense extract was most active against all tested isolates with MIC of 2.5% v/v against Staphylococcus species and Escherichia coli and 5% v/v against Klebsiella pneumoniae.

Conclusion: All the tested extracts showed varying spectra of inhibitions of the indicator organisms with Piper guineense the most active.