In Vivo Antimicrobial Activity of Plant Species on Escherichia Coli O157:H7 Inoculated into Albino Rats

Abstract

Escherichia coli O157:H7 is an enteric bacterium that has been implicated in outbreaks of disease worldwide and is currently considered an emerging pathogen. An investigation was carried out to determine the In vivo antimicrobial activity of 5 plant species (Allium sativum, Mangifera indica, Psidium guajava, Vernonia amgygdalina and Zingiber officinale) on E. coli O157:H7 inoculated into albino rats. The plant extracts were prepared according to standard method using ethanol as a solvent. An antibiotic (ciprofloxacin) served as a positive control. Five rats from each group were challenged with 1.0 ml of 109cfu/ml E. coli O157:H7 and simultaneously administered 3.0 mg extract of the plant species and the antibiotic drug per kg of rat body weight orally. The numbers of the pathogen shed in rat faeces were determined. The result revealed that there was a lot of variation in the percentage of the albino rats that shed the organism during the experiment. There was a significant interaction between treatment and time (p<0.05) over the course of the study. However, when comparing treatment groups at specific sampling days, the proportion of albino rats shedding faecal E. coli O157:H7 in the infected antibiotic-treated group was significantly higher (p<0.05) than infected non-treated group only on days 4 days. The present study has revealed that the ethanolic extracts of the plant species not only prevented the development of diarrhoea in rats treated with the plants but inhibited the growth of E. coli O157:H7 in them and thus have the ability to fight the pathogen as antimicrobial as well as anti-diarrhoeal agents.