Statistical optimization of production conditions of alkaline pectin lyase from Bacillus cereus using response surface methodology

Abstract

Alkaline pectin lyase finds applications in the degumming and retting of plant fibres, textile industry and pectic wastewater treatment where it degrades highly methylesterified pectin without prior action of any other pectinase. Response surface methodology (RSM) has been frequently utilized for the optimization of production process of industrially important enzymes from microbes. In the present work, fermentation conditions for the production of pectin lyase from Bacillus cereus were optimized using the factorial and central composite design of RSM. The cubic order polynomial regression model was found to be adequate and significant with a determination coefficient R² of 0.9505 (p < .0001). The ANOVA analysis and three-dimensional surface plots confirmed interaction among variables. The optimum values of variables were found to be pectin 4% (w/v), sodium carbonate 1% (w/v), manganese sulphate 0.055% (w/v) and magnesium sulphate 0.018% (w/v) at 150 rpm under response surface curves. After optimization using RSM, the experimental value of maximum activity of enzyme (3.37 U/ml) was found higher but close to the predicted value (2.68 U/ml) and the enzyme activity increased by 1.32-fold against activity of 1.43 U/ml using manual optimization.

Keywords:

• Pectin lyase
• response surface methodology
• Plackett–Burman design
• central composite design
• Pareto chart

Acknowledgements

The financial support to authors from Ministry of Science and Technology, Government of India, to the Department of Biotechnology, Himachal Pradesh University, Shimla (India), is thankfully acknowledged.

Disclosure statement

No potential conflict of interest was reported by the authors.