Abstract
Article History Aim: This study was designed to evaluate the antibacterial activities of water and ethanolic extracts of Nigerian herbs and spices against enteric pathogens. Methodology: Crude extracts of fresh leaves of Ocimum gratissimum, Psidium guajava, Vernonia amygdalina, Kigelia africana, Azadrichata indica, Pistia stratiotes, Euphobia hirta; bulb of Allum sativum and rhizomes of Zingiber officinale and Curcuma longa were evaluated using the agar diffusion assay method and minimal inhibitory concentration (MIC) to determine the antibacterial activities against Vibrio cholerae, Escherichia coli and Salmonella sp. Gentamicin (28 mg/ml) was used as antibiotic control. Results: Antimicrobial sensitivity test indicated that while Salmonella sp. was not inhibited by ethanolic extracts of Euphobia hirta and Curcuma longa, both water and ethanolic extracts of others inhibited the growth of Vibrio cholerae, Escherichia coli and Salmonella sp. to varying degree. The minimal inhibitory concentrations (MIC) determined for the crude extracts of the various herbs and spices, using water and aqueous ethanol inhibited the test isolates at high dilutions. Conclusion: This study has shown the antibacterial potential of the herbs and spices against the tested enteric pathogens. The antibacterial activities of all the herbs and spices observed in this study justify their use in alternative medicine.
Highlights
Medicinal plants have been used for centuries before the advent of orthodox medicine
Antibacterial activities of crude extracts of herbs and spices. Both the water and aqueous ethanolic extracts of Ocimum gratissimum, Vernonia amygdalina, Psidium guajava and spices Allium sativum, Curcuma longa and Zingiber officinale, Nymphae lotus, Euphorbia hirta, Ficus exasperata, Azadirachta indica, Kigelia africana and Pistia stratiotes showed varied degree of antibacterial activities against clinical Escherichia coli and Salmonella sp. and the epidemic strain of Vibrio cholerae tested in this study (Table 1)
The relatively high zones of inhibition exhibited by the ethanolic extract against Vibrio cholerae and Escherichia coli except Salmonella sp. which has no inhibition can be attributed to the fact that Vibrio cholerae and Escherichia coli are susceptible to the ethanolic extract
Summary
Medicinal plants have been used for centuries before the advent of orthodox medicine. Medicinal plants are distributed worldwide, but they are most abundant in tropical countries (Calixto, 2000; Lewis, 2001).
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
