In-Vitro Antibacterial Activities And Preliminary Phytochemical Screening Of The Aqueous And Ethanolic Extracts Of Zingiber Officinale

Abstract

Studies on the in-vitro antibacterial activities and phytochemical screening of the aqueous and ethanolic extracts of Zingiber officinale (ginger) against some clinical bacterial isolates (Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa) obtained from ear and urine samples were carried out using standard methods. Phytochemical screening revealed the presence of flavonoids, steroids, tannins and reducing sugars in both extracts while alkaloids and saponins were only present in the ethanolic and aqueous extracts respectively. In addition, a cream, soft and dark-brown ethanolic extract as well as solid, soft and black aqueous extract were recovered. The bioassay studies showed that the ethanolic extract exhibited an activity against S. aureus with 8 mm zone of inhibition at a concentration of 1000 μg/disc while no activity was recorded against E. coli and P. aeruginosa at the same disc potency. On the other hand, the aqueous extract was found to be more active against E. coli with 9 mm zone of inhibition at a comparatively higher concentration of 3000 μg/disc. The minimum inhibitory concentration ranged between 250 and 6000 μg/ml. Overall, the results of the study showed that the ethanolic and aqueous extracts of Z. officinale have antibacterial potentials against the tested clinical bacterial isolates, thus supporting the plant's ethnomedicinal uses.

Keywords: Zingiber Officinale, Extracts, Phytochemistry, Antibacterial Activity, MIC.