Growth and pathogenesis of Enteropathogenic E.coli as affected by bacteriocin produced and purified from Lactobacillus isolates with or without Quercus infectoria Hassan A. Abdul-Ratha¹ , Essam F. Al-Jumaily² and Rana H. Raheema

Abstract

The antimicrobial activity of Lactobacilli has been widely exploited for prevention of
food –borne pathogens e.g.: Escherichia coli being the major cause of diarrhea especially in
children, because of bacteriocin activity and the importance of herbal drugs, hence this study
was designed to evaluate the synergistic effect of plant extract and bacteriocin produced by
Lactobacillus on the growth and pathogenesis of Enteropathogenic Ecoli.
1. The Plantaricin production was induced by adding the mutagenic agent Mitomycin C.
2. Purification of Plantaricin was made by heating crude plantaricin at 80ºC for 10min and
then purified by two steps method including extraction with n-butanol followed by gel
filtration chromatography on Sepharose 6B column. The results showed that the specific
activity was 1600 AU/mg protein with 8 purification folds and 12% recovery yield.
3. The antibacterial activity of Quercus infectoria with concentration 300 mg/ml was
showed highly antibacterial activity in vitro and in vivo.
4. The result showed synergistic effect of Plantaricin with Quercus infectoria extract after
experimental infection that induced by orally dosing with Escherichia coli in vivo. A result of
histopathological study was recorded recovery of tissue.