Optimization of culture conditions for thermostable chitinase production by Paenibacillus sp. D1

Abstract

A hyper-chitinase producing isolate Paenibacillus sp. D1 was obtained from common effluent treatment plant of seafood industries at Veraval (Gujarat, India). The isolate exhibited chitinase production over a wide temperature (25 - 45°C) and pH (6 - 9) range with maxima at 30°C in medium with initial pH 7.0. The crude chitinase had activity in broad pH (4 - 10) and temperature (30 - 60°C) range with optima at pH 5.0 and 50°C, respectively. The enzyme was highly thermostable with t1/2 of 36 to 60 h at 40 and 45°C. Crab shell chitin, urea and K2HPO4were identified as best carbon, nitrogen and phosphorous sources influencing chitinase production by Paenibacillus sp. D1. Addition of tween 80 and FeCl3 enhanced the chitinase production by 1.44 and 1.33 fold, respectively. Identification of essential nutrients affecting chitinase production by Paenibacillus sp. D1 would help to formulate a suitable medium for its production. Moreover, low cost chitin from crab shells can be used as carbon source for thermostable chitinase production by the isolate for industrial and agricultural applications. Key words: Paenibacillus, optimization, thermostable, chitinase.