Optimal activity and biological activities of chitosanase produced from Bacillus subtilis EG1 and Bacillus wiedmannii DAM2

This study aimed to produce and characterize chitosan oligomers using chitosanases produced by two bacterial strains, Bacillus subtilis EG1 and Bacillus wiedmannii DAM2.Bacteria exhibiting chitosanase activity were first isolated and identified.The carbon and nitrogen sources were then optimized to maximize enzyme activity.Following optimization, chitosanase activity increased 54.4-fold and 6.7-fold in EG1 and DAM2, respectively.The basic characteristics of the two strains were subsequently investigated, and enzyme activity bands were analyzed by electrophoresis.The chitosan degradation patterns were examined using thin-layer chromatography, confirming the breakdown of chitosan into monosaccharides and hexasaccharides.Chitosan oligomers were further quantified by high-performance liquid chromatography, with total yields of 1.5% for EG1 and 5.3% for DAM2 at the optimal temperature and reaction time.In addition, the average molecular weight of chitosan was determined by gel permeation chromatography, and the optimal temperatures for chitosan oligomer production were identified as 60 o C for EG1 and 50 o C for DAM2.Collectively, our results confirmed that both EG1 and DAM2 produce active chitosanase enzymes capable of generating chitosan oligomers.These findings provide fundamental data supporting the industrial application of chitosanases derived from Bacillus spp.and for the large-scale production of high-valueadded chitosan oligomers.