O.O. Ojo*, A.O. Ajayi and I.I. Anibijuwon

Department of Microbiology, Faculty of Science, University of Ado-Ekiti, P.M.B 5363, Ado-Ekiti, Ekiti-State, Nigeria.


The antibacterial properties of three Nigerian spices – Zingiber officinale (ginger),
Allium sativum (garlic) and Piper guineense (African cola) – were tested against seven bacterial species. Extraction was done using ethanol and ethyl acetate for each of the spices. Extracts from Z. officinale and P. guineense showed less antimicrobial effects when compared with that of A. sativum. The extracts from A. sativum and Z. officinale were active against all microorganisms with zone of inhibition ranging from 0.2mm to 18.0mm. In general, the ethyl acetate extracts showed more activity then the ethanol extracts. Phytochemical screenings revealed the presence of only saponins in Z. officinale; saponins, tannins, phenolics and reducing compounds and alkaloids in Allium sativum and tannins, phenolics, reducing compounds and alkaloids in P. guineeense. The significance of the results obtained in this study are discussed.

Keywords: Antibacterial properties, Nigerian Spices.