Optimization of Fermentation Conditions for Chondroitinase Production by Pseudarthrobacter sp. PL-410

In order to determine its taxonomic status and to improve its enzyme production level, the chondroitinase-producing strain PL-410 was identified based on morphology and 16S rRNA gene sequence analysis, and the fermentation conditions for chondroitinase production by this strain were optimized by single factor experiments, Plackett-Burman design, the steepest ascent method and Box-Behnken design combined with response surface methodology. The results showed that the strain PL-410 was identified as Pseudarthrobacter sp. The optimal medium was composed of chondroitin sulfate from bovine cartilage 7.5 g/L, tryptone 2.5 g/L, NaCl 5 g/L, KH₂PO₄ 0.3 g/L, and initial pH 6.53. The optimal fermentation conditions were as follows: inoculum volume 2.98%, medium volume in shaking flasks 8%, shaker rotation speed 160 r/min, fermentation temperature 24 ℃, and fermentation time 27.63 h. The chondroitinase activity under these conditions was 2531.765 U/L, which was 29.7 times higher than that before optimization (85.229 U/L).