Optimization of chemical and physical parameters affecting the activity of pectin lyase and pectate lyase from Debaryomyces nepalensis:: A statistical approach

Debaryomyces nepalensis was previously isolated, which is capable of producing pectin lyase and pectate lyase using pectin as sole source Of carbon. The parameters affecting the activity of these enzymes are categorized into two, viz., chemical (amount of substrate and enzyme) and physical (pH of reaction mixture and temperature of incubation). The effect of these parameters on pectin lyase and pectate lyase was studied using central composite design. The optimal conditions of amount of substrate and enzyme (culture broth) were found to be 545 mu l (similar to 1 g/l pectin) and 123 mu l for pectin lyase and 707 mu l (similar to 1.1 g/l polygalacturonic acid) and 96 mu l for pectate lyase. The optimum pH and temperature for reaction was found to be 6.4 and 35 degrees C for pectin lyase and 7.5 and 32 degrees C for pectate lyase. After optimization, the activity of pectin lyase and pectate lyase was increased by 1.3- and 1.4-fold, respectively. (c) 2006 Elsevier B.V. All rights reserved.