These enzymes have a wealth of applications, some of which have already been realized by industry. Most of the chitinases are original from microorganisms such as Aspergillus, Bacillus, Trichoderma. The bioactivity of chitinase is affected by nutritional and enviromental conditions. This study emphasizes on the impact of critical process variables on the activity of chitinase from Aspergillus sydowii. The utilization of shrimp waste as a substrate for solidstate cultivation of the A. sydowii was investigated. The shrimp waste induces chitinase biosynthesis and it can be used to replace chitin in cultivation of A. sydowii for producing chitinase. Other factors influencing chitinase activity have been studied include source and content of nitrogen (urea, peptone respectively 0.33 g/10.5 g medium), moisture (40-70%), minerals (Cu²⁺, Fe²⁺, Pb²⁺), pH extract (phosphate buffer pH 6.0-7.5). The results showed that MT4 media containing 0.33 g (w/w) urea, 50% moisture, extraction phosphate buffer pH 7.0, are suitable for chitinase bioactivity. However, the mineral ions such as Cu²⁺, Fe²⁺ and Pb²⁺ inhibit chitinase bioactivity of A. sydowii. Research shows that using cheap sources of byproducts from shrimp shells as substrate to replace chitin also shows commercial benefits.

Keywords: Aspergillus sydowii, chitinase, chitin, shrimp shell waste.