Chitin degrading potential of three aquatic actinomycetes and its optimization

Eighty actinomycetes obtained from Krishna River in Satara district, India were screened for their chitinolytic activity on colloidal chitin agar. Fifty-two isolates showed clear zones of hydrolysis of chitin. Three isolates: Streptomyces canus, Streptomyces pseudogriseolus and Micromonospora brevicatiana were selected on the basis of zone of clearance to colony size ratio, for further studies. The period of optimum chitinase production was at 120 h for S. canus and 132 h for S. pseudogriseolus and M. brevicatiana. It was observed that S. canus and M. brevicatiana showed maximum activity from 40 to 60°C and S. pseudogriseolus showed maximum activity from 40 to 50°C. The optimum pH for chitinase production by all tested actinomycetes was at pH 8. S. canus and M. brevicatiana showed maximum activity at 1.2% chitin concentration and S. pseudogriseolus showed maximum activity at 1% substrate concentration.