The ever increasing energy demands of modern civilization and rapidly dwindling fossil fuels point towards a renewable substitute like biofuels. However, higher costs associated with biofuel productions is the major bottleneck for its commercialization. The present study demonstrates the use of a statistical approach called response surface methodology (RSM) to investigate the optimum parameters for maximum production of cellulase by Bacillus tequilensis G9. The Plackett–Burman design (PB) of the RSM analysis indicated grass straw (GS) concentration, pH, FeSO₄, inoculum, MgSO4, incubation period and NH₄Cl as significant variables that influence the cellulase production. Further, to propose the best medium for the maximum production of cellulase by B. tequilensis G9, the most influential parameters, namely concentrations of GS as substrate, FeSO₄, pH, inoculum size, etc. were fine-tuned by central composite design (CCD) involving four factors and five levels. The CCD analysis demonstrated 8% substrate concentration, 1.5% of inoculum along with 10 ppm FeSO₄ and a pH of 5.5 in media as optimum conditions for highest enzyme production. The field emission scanning electron microscopic analysis of the treated GS showed structural alterations depicting significant deconstruction caused by B. tequilensis G9. The yield of the partially purified cellulase proteins were found to be 21% revealing molecular mass between 30 and 97 kDa. The enhanced cellulase production by B. tequilensis G9 demonstrated in our study brands its applications in many industrial processes like biorefinery, biofuels, etc.

中文翻译：

---

统计优化木质纤维素废料的培养基以增强龙舌兰芽孢杆菌G9产生的纤维素酶

现代文明对能源的需求不断增长，而化石燃料的日渐减少，正朝着生物燃料等可再生替代品的方向发展。然而，与生物燃料生产相关的更高成本是其商业化的主要瓶颈。本研究表明使用一种称为响应表面方法（RSM）的统计方法来调查tequilensis G9纤维素酶最大产量的最佳参数。RSM分析的Plackett-Burman设计（PB）表明草秸秆（GS）的浓度，pH，FeSO ₄，接种物，MgSO 4，孵育时间和NH ₄ Cl是影响纤维素酶生产的重要变量。进一步，提出通过最大程度提高纤维素酶产量的最佳培养基tequilensis B9，最具影响力的参数，即作为底物的GS的浓度，FeSO ₄，pH值，接种量等，通过涉及四个因素和五个层次的中央复合设计（CCD）进行了微调。CCD分析表明，培养基中8％的底物浓度，1.5％的接种物以及10 ppm FeSO ₄以及培养基中的pH值5.5是获得最高酶产量的最佳条件。经处理的GS的场发射扫描电子显微镜分析显示结构变化，表明由B. tequilensis G9引起的显着解构。发现部分纯化的纤维素酶蛋白的产率为21％，揭示了30至97kDa之间的分子量。龙眼芽孢杆菌提高了纤维素酶的产量 G9在我们的研究品牌中展示了其在许多工业过程中的应用，例如生物炼制，生物燃料等。