(A) Influence of metal ions on chitinase activity at different concentration (1 mM and 5 mM) of divalent cations. (B) Effect of chemical reagents on chitinase activity at 1 mM and 5 mM concentration. (C) Effect of solvents on chitinase activity at different percentages (1%, 5%). The enzyme was assayed at 60 °C and pH 5.5. Untreated enzyme was used as the control (defined as 100% activity). The data is representative of the mean of three experiments.