Optimization Of Cellulase Production By The High Yeild Cellulase Production Strain Trichoderma Harzianum EUB11 And OPEFB Enzymatic Hydrolysis And Diastatic Fermentation

This studies described the optimization of process parameters for the production of cellulolytic enzymes by Trichoderma harzianum EUB11 using the liquid submerged fermentation technique. Preatretment of oil palm empty fruit bunch(OPEFB) and its enzymatic hydrolysis saccharification fermentation were also investigated in this study.Trichoderma harzianum EUB11 was a mutant which has an efficient cellulase production system and its original strain which is filamentous fungi was selected form nature. During the process of lignocellulose to bioethanol, the production of cellulase production was the frist step, and then was the pretreatment of lignocellulose, ethanol fermentation was the final step. The high cost of cellulase production and hydrolysis incompletely of lignocellulose were obstacles for the conversion of lignocellulose to bioethanol. Thus reducing the cost of cellulose production and the component of lignin in lignocellulose were the emphasis of the study. In this work, oil palm fruit bunch was used for bio ethanol production.The period of the seed, optimization of inducer and medium for cellulase production by Trichoderma harzianum EUB11 were investigated in this work. The result demonstrated that Solka Floc cellulose was the best inducer for cellulase production and the optimum concentration was 50 g/L, the most efficient nitrogen sources were(NH4)2SO4 and Urea and the best ratio of them was 3:2, the optimum C/N was 8:1, the optimum concentration of wheat bran was 40g/L, and the optimum concentration of Na H2PO4 was 13g/L. The value of the FPase of crude enzymes from EUB11 with the optimum medium was 1.65 times compared with that from old medium, the CMCase was 1.60 times, the xylanase was2.43 times, ?-glucosidase was 2.12 times and ?-xylosidase was 2.52 times, what's more,the fermentation period was shorten from 8 to 6 days. The result showed that the optimum medium was more suitable for cellulase production than the old medium. There was also fed-batch fermention for cellulase production by EUB11 and the resulted demonstrated that high concentration of feeding was negative for cellulase produced and low concentration of feeding was similar with batch which showed that fed-batch has a slight effect on cellulase production. For oil palm fruit bunch( OPEFB) pretreatment, the result showed that 4%Na OH treated OPEFB residues for 1 h at 121oC, and then 1% H2O2 treated the OPEFBresidues for 12 h at 50 o C, the cellulose component was 53.86% and the hemicellulose component was 23.62% after pretreatment, and the value was better than others. Cellulose was replaced by pretreated OPEFB residues as the substrate for cellulase production by the strain EUB11 and the FPase of the crude cellulase was 8.1IU/m L, 75.56 FPase/g substrate,the concentration of the protein was 7.9mg/m L and the special enzyme activity was1.02mg/m L. The cellulase was performed on OPEFB residues hydrolysis and the result was compared with commercial cellulase(C1.5 L) and mixture commercial cellulase(C1.5L and N188), after 96 hydrolysis the glucose concentration was 34.0g/L(EUB11), 29.5g/L(C1.5L), 38.1g/L(C1.5L+N188), respectively, and the xylose concentration was 18.1g/L(EUB11), 15.1 g/L(C1.5L), 18.2 g/L(C1.5L+N188), separately. The performance of catalysis of cellulase from EUB11 was better than commercial cellulase(C1.5 L) without any additional enzymes, what's more, for xlylose production, the performance of catalysis of cellulase from EUB11 was well as commercial mixed cellulase(C1.5 L+N188). Effect of different solid loading on OPEFB residues enzymatic hydrolysis was obtained in this study and the result showed that the higher solid loading of the substrate would lead to the higher concentration of sugars, however, the higher solid loading of the substrate would not result in higher conversion of cellulose and hemicellulose, in this work, the best conversion of cellulose and hemicellulose was appeared at 10% solid loading. At last, the fermentable of sugars in the enzymatic hydrolysate was tested by the saccharomyces cerevisiae which was keeped in our lab. After 24 h fermentation, glucose and xylose in the enzymatic hydrolysate were all utilized completely and 26.5 g/L of ethanol was obtianed with the yeast strain, and the ethanol production was similar with the control which was26.4g/L.