Antimicrobial activity of Azadirachta indica and Allium sativum L extracts against enteropathogenic Escherichia coli (EPEC) and shiga toxin producing Escherichia coli (STEC)

The present study was undertaken to record the in vitro antimicrobial efficacy of crude aqueous, methanolic and ethanolic extract of Neem leaves (Azadirachta indica) and Garlic bulb (Allium sativum L.) against enteropathogenic Escherichia coli (EPEC) and Shiga toxin producing Escherichia coli (STEC) isolated from neonatal calf diarrhoeal samples. The significant antibacterial activity was observed against various EPEC and STEC serogroups in aqueous and ethanolic extracts of neem leaves. The aqueous extract of garlic also showed activity against EPEC and STEC serogroups. However, methanolic extracts of both the herbals and ethanolic extract of garlic at different concentrations showed mild antimicrobial activity. None of the extracts could act against O8 serogroup.