Application of Response Surface Methodology for Optimization of Extracellular Glucoamylase Production by Candida guilliermondii

Objective: Glucoamylase is among the most important enzymes in biotechnology. The present study aims to determine better conditions for growth and glucoamylase production by Candida guilliermondii and to reduce the overall cost of the medium using Box-Behnken design with one central point and response surface methodology. Methodology: Box-Behnken factorial design based on three levels was carried out to obtain optimal medium combination of five independent variables such as initial pH, soluble starch, CH₄N₂O, yeast extract and MgSO₄. Forty one randomized mediums were incubated in flask on a rotary shaker at 105 rpm for 72 h at 30°C. Results: The production of biomass was found to be pH and starch dependent, maximum production when the starch concentration was 8 g L¹ and the initial pH was 6, while maximum glucoamylase production was found at 6.5 of initial pH, 4 g L¹ yeast extract and 6 g L¹ starch, whereas yeast extract and urea were highly significant, but interacted negatively. Box-Behnken factorial design used for the analysis of treatment combinations gave a second-order polynomial regression model with R² = 0.976 for Biomass and R² = 0.981 for glucoamylase. Conclusion: The final biomass and glucoamylase activity obtained was very close to the calculated parameters according to the p-values (p<0.001), the predicted optimal parameters were confirmed and provides a basis for further studies in baking additives and in the valuation of starch waste products.

from #AlexandrosSfakianakis via Alexandros G.Sfakianakis on Inoreader http://ift.tt/2iU9Nsc
via IFTTT