Optimization of cold-active chitinase production from the Antarctic bacterium, Sanguibacter antarcticus KOPRI 21702

Abstract

In the present study, cultivation conditions and medium components were optimized using statistical design and analysis to enhance the production of Chi21702, a cold-active extracellular chitinase from the Antarctic bacterium Sanguibacter antarcticus KOPRI 21702. Identification of significant carbon sources and other key elements was performed using a statistical design technique. Chitin and glycerol were selected as main carbon sources, and the ratio of complex nitrogen sources to carbon sources was determined to be 0.5. Among 15 mineral components included in basal medium, NaCl, Fe(C₆H₅O₇), and MgCl₂ were found to have the most influence on Chi21702 production. The optimal parameters of temperature, initial pH, and dissolved oxygen level were found to be 25°C, 6.5, and above 30% of air saturation, respectively. The maximum Chi21702 activity obtained under the optimized conditions was 90 U/L. Through statistical optimization methods, a 7.5-fold increase in Chi21702 production was achieved over unoptimized conditions. Chi21702 showed relatively high activity, even at low temperatures close to 0°C. The information obtained in the present study could be applied to the production of cold-active endochitinase on a large scale, suitable for a process at low temperature in industry.