The study highlights the production of chitinase from Bacillus cereus BSH-4, which was isolated from a marine soil source and identified by 16S rRNA gene sequencing. After 96 hours of incubation in shake flask conditions profiling studies showed maximum enzyme activity and growth. The ammonium sulfate precipitation method was used at 80% saturation for partial enzyme purification with further purification done by dialysis wherein the purification fold increased to 1.75. The sodium dodecyl sulfate gel electrophoresis (SDS-PAGE) and silver staining methods were employed to assess the enzyme molecular weight observed to be 60 kDa. The enzyme activity and stability process parameters effects like temperature and pH were studied. At a pH value of 7.0, the greatest enzyme activity was noted which was relatively retained at 80% till pH 9.0. Similarly, higher enzyme activity was observed at a temperature of 30oC and retained 70% relative activity till 60oC, indicating the thermostable nature of the enzyme. Studies on the influence of metal ions showed that Zn2+, Cu2+, Ca2+, Mg2+, Mn2+, and Fe2+ inhibited the enzyme by 20% to 80%. An investigation was also done on the influence of organic solvents like methanol, ethanol, acetone, and isopropyl alcohol on enzyme stability. The results showed that the enzyme was stable in all the solvents, exhibiting 43% to 70% relative activity. The enzyme kinetic studies indicated Km and Vmax values of 4.54 mg ml-1 and 76.92 UmL-1, respectively. The enzyme also demonstrated antifungal activity against Aspergillus niger NCIM 1207 using the agar well diffusion method.
