Singhania Reeta Rani, Sukumaran Rajeev K, Pandey Ashok
Biotechnology Division, National Institute for Interdisciplinary Science and Technology (formerly Regional Research Laboratory), Industrial Estate PO, Trivandrum, India.
Appl Biochem Biotechnol. 2007 Jul;142(1):60-70. doi: 10.1007/s12010-007-0019-2.
The major constraint in the enzymatic saccharification of biomass for ethanol production is the cost of cellulase enzymes. Production cost of cellulases may be brought down by multifaceted approaches which includes the use of cheap lignocellulosic substrates for fermentation production of the enzyme, and the use of cost efficient fermentation strategies like solid state fermentation (SSF). The current study investigated the production of cellulase by Trichoderma reesei RUT C30 on wheat bran under SSF. Process parameters important in cellulase production were identified by a Plackett and Burman design and the parameters with significant effects on enzyme production were optimized for maximal yield using a central composite rotary design (CCD). Higher initial moisture content of the medium had a negative effect on production whereas incubation temperature influenced cellulase production positively in the tested range. Optimization of the levels of incubation temperature and initial moisture content of the medium resulted in a 6.2 fold increase in production from 0.605 to 3.8 U/gds of cellulase. The optimal combination of moisture and temperature was found to be 37.56% and 30 degrees C, respectively, for maximal cellulase production by the fungus on wheat bran.
生物质酶解糖化生产乙醇的主要制约因素是纤维素酶的成本。可通过多方面途径降低纤维素酶的生产成本，包括使用廉价的木质纤维素底物进行酶的发酵生产，以及采用成本效益高的发酵策略，如固态发酵（SSF）。本研究调查了里氏木霉RUT C30在固态发酵条件下利用麦麸生产纤维素酶的情况。通过Plackett-Burman设计确定了纤维素酶生产过程中的重要工艺参数，并使用中心复合旋转设计（CCD）对影响酶产量的显著参数进行优化以实现最大产量。培养基较高的初始水分含量对产量有负面影响，而在所测试的温度范围内，培养温度对纤维素酶生产有积极影响。对培养温度和培养基初始水分含量水平进行优化后，纤维素酶产量从0.605 U/gds提高到3.8 U/gds，增长了6.2倍。发现水分和温度的最佳组合分别为37.56%和30℃，此时该真菌在麦麸上生产纤维素酶的产量最高。
