solation of tannase producers from soil

Abstract

The enzyme tannase hydrolyses the ester bonds of tannic acid to release gallic acid and glucose. Tannic acid is known to be bacteriostatic but a few organisms are resistant to it by producing tannase enzyme. Frequently used assay for tannase is the isolation of tannase producers in the presence of tannic acid on a nutrient plate. An attempt has been made to find isolation procedures for tannase producers and eliminate the false positive results. Tannic acid is an integral and important plant constituent. Thus soil samples would logically be an excellent source for the isolation of tannase producing bacteria. These samples were collected from Mumbai and Thane region. The samples were plated onto nutrient agar plates containing 2% tannic acid. Isolates showing a halo of clearance around the colonies were selected and screened to confirm their tannase producing ability. Amongst the cultures obtained, one bacterial tannase producer was obtained which showed relatively high enzyme activity. The bacterial isolate was identified and characterised using various biochemical tests. This paper highlights the use of different methods for the isolation of tannase producers, thus, eliminating chances of selecting an isolate that demonstrates false positive results.