ENVIRONMENTAL BIOTECHNOLOGY

Experiment 11

Aim of the Experiment : Confirmed test for coliform bacteria.

Introduction

This test is named so because, positive presumptive tubes having acid and gas are subjected to further confirmation that positive results were due to coliforms only. Test involves, streaking of eosin methylene blue (EMB) agar or Endo's agar plate and looking for the growth of typical &/or atypical colonies of coliforms.

Materials required

1. Positive presumptive tube(s).

2. EMB agar plate.

Procedure:

1. Streak a loopful of suspension from a positive presumptive tube (which shows the highest amount of gas production), so as to get well isolated colonies.

2. Incubate the plate at 37 °C for 24 hours.

3. Record results and interprete.