Isolation of bacteria producing chitin-degrading enzymes and preliminary studies on their optimum fermentative conditions.

Two strains designated as Pseudomonas sp ww and Brevibacterium sp yy were isolated from soil samples based on their chitindegrading characteristics On broth medium, Brevibacterium sp yy and Pseudomonas sp ww reached their stationary phase after shaken for 16 h and 20 h respectively, while on chitin medium, 36 hours were needed for both strains to that phase Determination of enzyme activities showed that strain yy reached its highest of 83 U/mL at 35 h and strain ww got to 133 U/mL at 30 h The batch cultivation with feeding 02% colloid chitin to half broth medium at 10 h could bring forward 5 h for enzyme secreting: strain yy reached its highest of 84 U/mL at 30 h and strain ww 156 U/mL at 25 h But feeding 2% colloid chitin would inhibit the growth of two strains, especially to strain yy It was also showed that both chitin cultures could inhibit the growth of Staphylococcus aureus and Escherichia coli, but had no such action to Aspergillus niger and Rhizopus niger