Raza Ahmad, Bashir Saira, Tabassum Romana
National Institute for Biotechnology and Genetic Engineering (NIBGE), P.O. Box 577, Jhang Road, Faisalabad, Pakistan.
Pakistan Institute of Engineering and Applied Sciences (PIEAS), Islamabad, Pakistan.
Folia Microbiol (Praha). 2019 May;64(3):295-305. doi: 10.1007/s12223-018-0654-8. Epub 2018 Oct 25.
Endo-glucanase (cellulase) and xylanase have high industrial demand due to their vast application in industrial processes. This study reports statistical based experimental optimization for co-production of endo-glucanase and xylanase from Bacillus sonorensis BD92. Response surface methodology (RSM) involving central composite design (CCD) with full factorial experiments (2) was applied to elucidate the components that significantly affect co-production of endo-glucanase and xylanase. The optimum co-production conditions for endo-glucanase and xylanase were as follows: carboxymethyl cellulose (CMC) 20 g/L, yeast extract 15 g/L, and time 72 h. The maximum endo-glucanase and xylanase production obtained was 1.46 and 5.69 U/mL, respectively, while the minimum endo-glucanase and xylanase production obtained was 0.66 and 0.25 U/mL, respectively. This statistical model was efficient because only 20 experimental runs were necessary to assess the highest production conditions, and the model accuracy was very satisfactory as coefficient of determination (R) was 0.95 and 0.89 for endo-glucanase and xylanase, respectively. Further, potential application of these enzymes for saccharification of lignocellulosic biomass (wheat bran, wheat straw, rice straw, and cotton stalk) was also investigated. The results revealed that the biomass was susceptible to enzymatic saccharification and the amount of reducing sugars (glucose and xylose) increased with increase in incubation time. In conclusion, Bacillus sonorensis BD92 reveals a promise as a source of potential endo-glucanase and xylanase producer that could be useful for degrading plant biomass into value-added products of economic importance using precise statistically optimized conditions.
内切葡聚糖酶（纤维素酶）和木聚糖酶因其在工业生产中的广泛应用而具有很高的工业需求。本研究报道了基于统计学的实验优化方法，用于从索诺拉芽孢杆菌BD92中联产内切葡聚糖酶和木聚糖酶。采用响应面法（RSM），结合全因子实验的中心复合设计（CCD）（2）来阐明显著影响内切葡聚糖酶和木聚糖酶联产的因素。内切葡聚糖酶和木聚糖酶的最佳联产条件如下：羧甲基纤维素（CMC）20 g/L、酵母提取物15 g/L、时间72 h。获得的内切葡聚糖酶和木聚糖酶的最大产量分别为1.46和5.69 U/mL，而获得的内切葡聚糖酶和木聚糖酶的最小产量分别为0.66和0.25 U/mL。该统计模型是有效的，因为仅需20次实验运行就能评估最高产量条件，并且模型准确性非常令人满意，内切葡聚糖酶和木聚糖酶的决定系数（R）分别为0.95和0.89。此外，还研究了这些酶在木质纤维素生物质（麦麸、小麦秸秆、水稻秸秆和棉秆）糖化中的潜在应用。结果表明，生物质易于酶解糖化，还原糖（葡萄糖和木糖）的量随孵育时间的增加而增加。总之，索诺拉芽孢杆菌BD92有望成为潜在的内切葡聚糖酶和木聚糖酶生产者，利用精确的统计学优化条件将植物生物质降解为具有经济重要性的增值产品。
