Synergistic Effects Of Biomass Apoplast Protein On Cellulase, And Exploring Its Extraction Technique

In this thesis, the author studied the alteration of the maize straw apoplast proteins in the process of preservation, analyzed the effects of apoplast proteins on Penicillum expansum cellulase activities, and suggested extraction technique of apoplast proteins.The results show that: The extractable apoplast proteins are gradually decreased during the preservation of maize straw. The content of apoplast proteins in the 6- month kept maize straw is only 34.71% that in the fresh straw. After half year preservation, the speed of protein degradation or inactivation attenuated and the proteins content was almost stable. There is not endogenous cellulase activity in preserved maize straw, while apoplast proteins extracted from fresh maize straw possess endogenous EG activities, which is unstable and completely vanished after 6 months preservation.There is an obvious synergistic effects relationship between apoplast proteins and P. expansum, and this synergistic effect decreases along with preservation. When the concentration of the apoplast proteins is 1 mg/ml in the reaction system, the apoplast proteins from the preserved straw exhibit significant synergistic effect on PFA, cotton lyase and β-glucosidase. The maximal synergistic values are 95.32% 102.06% and 96.6%, respectively. But interestingly, they inhibit the CMCase activity, while the maximum inhibit ratio reaches 49.52%. From the relations between apoplast proteins and each component of P. expansum cellulose, the main synergistic exhibition is apoplast proteins-EG-BG, and without any effect on CBH activity which is the core factor in the cellulase hydrolysis. After eliminating the effect of endogenous EG, the apoplast proteins from fresh...