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For China's resource-rich plant fiber, while the use of inadequate characteristics, the the enzymatic saccharification fiber raw material process. Through the study of the solid-state fermentation of Trichoderma reesei strains (Trichoderme reesei ATCC 56764), show that the strain can utilize xylose residue enzyme production. The control medium water content of 70%, initial pH is a natural value, the culture temperature is selected in the initial 30 ° C, dropped to 25 ° C, when the amount of bacteria is accumulated to a certain extent after the culture conditions, the filter paper activity ( FPA) up to 158 IU / g song, but the bacteria produced cellobiase low capacity. Studies have shown that solid-state fermentation of Aspergillus niger (Aspergillus niger LORRE 012): the bacteria filter paper activity is very low, but it is the cellobiase the high yield strains, when control and Trichoderma reesei same culture conditions, the CBA highest up to 435.6 IU / g song. Pretreatment with different methods of fiber materials, then were treated with cellulase hydrolysis investigated the impact of different pretreatment methods for enzymatic effect. The results showed that: dilute acid treatment most of the hemicellulose degradation, so that the substrate of the enzymatic efficiency increased significantly; sodium hydroxide to a strong role in the removal of lignin and hemicellulose, the enzymatic efficiency of the substrate is very high, but the cost is expensive; ammonia relatively low processing costs, and reduces the loss of hemicellulose to be improved, but the efficiency of enzymatic hydrolysis of cellulose, hemicellulose and lignin; steam explosion treatment have different degrees of decomposition. enzymatic efficiency is also high, but high requirements of the equipment. The research on the enzymatic hydrolysis process conditions: different substrate concentrations and enzyme volume has some influence on the enzymatic hydrolysis efficiency. Substrate concentration is small, the enzymatic hydrolysis less sugar concentration is too large hydrolysis yield decline, so the use of 100 g / L more reasonable. Enzyme dosage 15 FPIU / g appropriate, no significant effect on improving enzymatic efficiency continues to increase. Abstracts of Zhejiang University, a master's degree in the enzymatic process, early glucose content linear growth, cellobiose content is very low: 48 h after glucose content reached saturation, the cellobiose significant accumulation. Cellobiose enzyme inhibition, as well as cellobiose and glucose on the inner cut type and exo-type p-glucanase feedback. When used inside Trichoderma reesei cellulase hydrolysis of fiber materials, adding a certain amount of Aspergillus niger by the middle of cellobiase, can eliminate the feedback inhibition of the product of sugar. CBA / FPA increased to 0.42 from 0 knife upcoming Richter Trichoderma cellulase the fiber h sugar enzyme activity increased about 14 times, the hydrolysis yield can be increased by 74.5% to gi. 6%. Enzymatic hydrolysis of the fibrous raw material into fermentable sugars further used in the production of alcohol, single cell protein, organic acids, not only comprehensive utilization of a large number of agricultural and industrial fiber waste, and reduce environmental pollution, the implementation of the strategy for sustainable development There are significant.
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