摘要
分批添加可溶性淀粉水解液可促进固定化里氏木霉(Trichoderma reesei RutC30)细胞合成纤维素酶。不同分批添料量对固定化细胞产酶有着明显的影响,当日添加量为0.3％(还原糖)时,滤纸酶活力(FPA)和纤维二糖酶(CB)活力分别可达3.12IU/mL和0.43IU/mL。产酶动力学研究结果表明,固定化细胞总量在产酶过程中保持着动态平衡。pH值开始稳定,以后逐步上升。FPA、CB活力和可溶性蛋白质含量的变化与pH值密切相关,当pH值上升时,它们均明显提高;而当pH值接近7时,则急剧下降。固定化细胞以淀粉水解液为碳源合成的纤维素酶,对玉米秸秆具有明显的降解作用,当每克底物的酶用量为20个滤纸酶活力国际单位(FPIU)时,酶解得率达86.2％,显示了很大的应用潜力。
The production of cellulase can be promoted by immobilized cells of Trichoderma reesei Rut C30 in a fed-batch fermentation using soluble starch hydrolysate. The manner to supply soluble carbon source has obvious effects on cellulase activities. It was found that feeding 0. 3% (reducing sugars) per day was suitable for cellulase production, with resultant filter paper and cellobiase activities being 3.12 IU/mL and 0. 43 IU/mL respectively. The kinetics of cellulase production under our standard fermentation conditions have been presented:the quantity of the immobilized cells remained in a state of kinetic equilibrium over the whole process (the pH value was stable at the beginning of the cultivation, afterwards, rose continuously; the time courses of filter paper activity and soluble protein were similar; both increased slowly at first, then increased fast coincidentally with the rise of pH value and rapidly declined when the pH value was near 7.0;the cellobiase activity rose sharply only at the higher pH value (5.0～6.5),which may relate to autolysis of the cells.
The cellulase produced by the immobilized cells on the soluble starch hydrolysate has strong degrading ability on corn stover. When the cellulase dosage was 20 FPIU/g,the hydrolysis efficiency reached 86.2%, showing a good application potential.
出处
《林产化学与工业》
EI
CAS
CSCD
北大核心
1993年第3期217-222,共6页
Chemistry and Industry of Forest Products
关键词
细胞
纤维素酶
淀粉
水解液
固化
Immobilized cell
Cellulase
Fed-batch fermentation
Starch hydrolysate
