Statistical screening of media components for the production of arginine deiminase by Weissella confusa GR7 Kaur Baljinder*, Kaur Rajinder Department of Biotechnology, Punjabi University, Patiala, Punjab, India *Email: baljinderbt@hotmail.com
Online published on 19 March, 2013. Abstract A lactic acid bacterial strain capable of metabolizing arginine via arginine deiminase pathway was isolated from lassi, an Indian fermented food. On the basis of biochemical analysis it was identified as Weissella confusa. Response surface methodology (RSM) was used to optimize media components such as carbon and nitrogen sources, minerals, inducers and metal ions for enhancing its specific arginine deiminase activity. A Placket-Burman design was applied to identify significant factors affecting enzyme production in Weissella confusa GR7. Central composite rotatable design was applied further to optimize the concentrations of sucrose, copper, magnesium, manganese and arginine for maximizing arginine deiminase activity. Statistical design has suggested a Two Factor Interaction model which was validated experimentally where it showed 10 fold increases in specific arginine deiminase activity over basal medium. By solving the regression equation and analyzing the response surface cartons, optimal concentration of various components was determined as 2.5g/l sucrose, 5g/l fructose, 10g/l tryptone, 5mM MgSO4, 5mM MnSO4, 25mM arginine, 5mM Copper, 50mg/ml CTAB and 50mM Tween 80. The model was found satisfactory as the coefficient of determination was 0.83. Results indicate an improved arginine deiminase production in statistically optimized medium using response surface methodology. Top Keywords Arginine deiminase, Weissella confusa, Central composite rotatable design, Response surface methodology, Lactic acid, Bacteria. Top |