Phytochemical Profile and Antibacterial Effects of Zingiber Officinale Root Extract on Some Enteric Bacterial Pathogens

Abstract

The majority of Africans today depend either totally or partially on medicinal plants for the treatment of various diseases. In some rural communities, ethno-medicine is sometimes the only form of healthcare. Therefore, this work aimed to determine the phytochemical constituents and antibacterial potentials of Z. officinale, which is one of the medicinal plants used by some people. The active ingredients of the plant were first extracted using water and ethanol as solvents. This was followed by the phytochemical analysis of the extracts. Furthermore, the antibacterial effects of aqueous and ethanolic extracts of Z. officinale on Escherichia coli, Salmonella typhi and Shigella dysenteriae isolated from faeces of gastroenteritis patients were evaluated using the agar diffusion technique (punch method). Additionally, a two-fold tube dilution method was used to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the extracts. The mean values of zones of inhibition obtained were statistically analyzed using ANOVA. The least significant difference was determined according to the LSD test at P<0.05. Phytochemical analysis revealed the presence of saponin, alkaloids, flavonoids, and tannins. The antibacterial results showed that both the aqueous and ethanolic extracts have antibacterial effects against all the test organisms but at varying degrees. At the 500mg/ml concentration, the ethanolic extract of Zingiber officinale produced a zone of inhibition of 21.00b against S. dysenteriae and 20.00b against E. coli and S. typhi. On the other hand, the 500mg/ml concentration of the aqueous extract had a zone of inhibition of 20.00b against S. dysenteriae, 16.00b against E. coli and 10.00b against S. typhi. The findings from this study lend credence to the claims that Z. officinale extracts possess antibacterial potentials. Also, the higher potency in ethanolic than in aqueous extract suggests that the potency might be dose and solvent dependent. Conclusively, owing to the findings from this study, the active ingredients of Z. officinale could be harnessed and employed in the development of novel antibacterial therapies.