Greener Journal of Biological Sciences Vol. 3 (6), pp. 238-243, August 2013.
© 2011 Greener Journals
Manuscript Number: 072913760
Antibacterial Activity of Ethanol Extract ofPhoenix dactylifera Leaves against some Gram Negative Bacterial Isolates
*1Lawal Garba, 2Muhammad Yusha’u and
1Microbiology Unit, Department of Biological Sciences, Gombe State University, P.M.B 127, Gombe State, Nigeria.
2Department of Microbiology, Bayero University, Kano, P.M.B. 3011, Kano State, Nigeria.
*Correspondence Author’s Email: lagarpak @yahoo .com, lagarpak @ gmail.com
This research was conducted at Gombe State University, Gombe State, Nigeria from January to July, 2013. The research aimed at determining the antimicrobial activity of ethanol extract of Phoenix dactylifera leaves against four clinical isolates of Gram negative bacteria using Agar Disc diffusion technique. The Gram negative bacteria screened included; Escherichia coli, Morganella morganii, Proteus mirabilis and Yersinia enterocolitica. Four different concentrations tested included 20µg/disc, 40µg/disc, 80µg/disc and 160µg/disc which revealed a strong in vitro antibacterial activity against all the test organisms. Of these organisms tested, E. coli was found to be the most sensitive, followed by P. mirabilis and Y. enterocolitica producing the same zones of growth inhibition and the least sensitive organism being M. morganii. Minimum Inhibitory Concentration (MIC) was determined at 25µg/ml for all the test organisms while the Minimum Bactericidal Concentration (MBC) was probably above 100µg/ml at the highest concentration used because the organisms still managed to grow when sub-cultured on the solid media. This indicates that Phoenix dactylifera leaf extract is bacteriostatic against the test isolates used in this study.
Keywords: Antibacterial activity, Phoenix dactylifera leaf, Extracts, Clinical isolates