A new selective and differential agar medium for Escherichia coli and coliform organisms

Abstract

An enriched lauryl sulfate-aniline blue agar medium which is selective for E. coli and coliform organisms is described. From fecal samples, the medium gave higher counts of colonies producing acid from lactose than media containing bile salts. From contaminated water and food samples, the medium gave comparable or higher counts of colonies identified as E. coli than standard media. Colonies of E. coli were more readily differentiated from those of other coliform organisms.