Identification of a chitin deacetylase producing bacteria isolated from soil and its fermentation optimization.

Abstract

Chitin deacetylase (CDA) catalyzes the conversion of chitin to chitosan by the deacetylation of N-acetyl-D-glucosamine residues. In this study, 9 strains of bacteria with chitin deacetylase activity were isolated from canal mud samples from theXiangjiang River in Changsha, Hunan Province. Of these 9 strains, the Z7 strain had the highest chitin deacetylase activity, as determined by enzyme assay screening. Based on its culture, morphological, physiological characteristics and molecular identification, strain Z7 was identified as Bacillus amyloliquefaciens. Yeast extract at a concentration of 1.0% was an ideal nitrogen source for production of CDA (16.78 Eu/ml). Starch at 2% functioned best as the major carbon source for optimum production of CDA (17.84 Eu/ml). Magnesium sulfate at a concentration of 0.04% was an ideal inorganic salt for CDA production (17.45 Eu/ml). Ideal pH and temperature for optimum production of CDA by this strain were pH 6 and 37EsC. Key words: Chitin deacetylase, Chitosan, Bacillus amyloliquefaciens.