Optimization of concurrent production of xylanolytic and pectinolytic enzymes by Bacillus safensis M35 and Bacillus altitudinis J208 using agro-industrial biomass through Response Surface Methodology

Application of crude xylanolytic and pectinolytic enzymes in diverse industrial processes make these enzymes commercially valuable and demand their production process to be cost-effective. Out of four different agrowaste biomass, wheat bran (WB) and citrus peel (CP), when amended as fermentation substrates, respectively induced the highest xylanolytic enzymes and pectinolytic enzymes from both, B. safensis M35 and B. altitudinis J208. Further, the simultaneous amendment of WB and CP yielded concurrent production of these cellulase free xylanolytic and pectinolytic enzymes. Hence, the quadratic model was developed using the Central Composite Design of Response Surface Method (CCD-RSM). The model gave the concentration values for WB and CP substrates to be amended in one single production medium for obtaining two optimized predicted response values of xylanase activity and pectinase activity units, which were further practically validated for the xylanase and pectinase production responses from the optimized production medium (OPM). These practically obtained response values from OPM were found to be in accordance with a range of 95% predicted intervals (PI) values. These observations verified the validity of the predicted quadratic model from RSM and suggested that both xylanase and pectinase enzymes can be induced concurrently from both of the bacterial strains.