Optimization of medium composition to induce cellulase production of Bacillus sp. by Response Surface Methodology

Abstract

In the past, optimization in biological analyses has been performed by measuring influence of one factor at a time. The disadvantage of this technique is not presence any interactive effects of factors studies and it needs a large number of experiments. Consequently, the Response Surface Methodology (RSM) is the most popular choice for optimization. It used the effects of mathematics and statistics to study optimization with minimum experimental trials and therefore interactive variables may be involved. This study has selected and screened seven Bacillus strain in Vietnam Type Culture Collection which can product cellulase in the medium with CMC as an inducer. VTCC-B-0497 presented the best result. Then, only 15 experiments of design matrix by Box-Behnken were necessary to determine optimal concentrations of three variables including the concentration of Carboxymethylcellulose, Yeast extract and Meat extract to product cellulase. The model could be employed to predict the response. The maximum of cellulase activity was 2.48 U at the concentration of Carboxymethylcellulose 0.25% w/v, yeast extract 0.7% w/v and meat extract 0.2% w/v.