Enhanced production of dextransucrase by L. mesenteroides MTCC 867 using response surface methodology

Abstract

In the present study, basal MRS medium was developed by screening of different media components for dextransucrase production for L. mesenteroides MTCC 867. Important MRS media components were screened by Placket Burman method. Further response surface methodology was applied for important media components using central composite design for enhanced enzyme production. The optimum values for the tested variables were; sucrose 34.01%, bacteriological peptone 1.22%, yeast extract 0.88% and K₂HPO₄ 1.62%. A quadratic polynomial equation was suggested and then validated experientially. Validation was carried out in shake flasks under conditions predicted by the model. The predicted yield was 782.68 DSU/mL. On experimentation 760.58 DSU/mL dextransucrase was obtained. The experimental values were found to be very close to the predicted values and hence, the model was successfully validated. This activity is very high as compared to most of the reports. The dextransucrase production was increased by 8.63 fold over the basal medium.