الفهرس 
Production of cellulasesOnly 14 pages are availabe for public view
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Abstract
The production of soluble sugars by enzymatic hydrolysis of cellulosic matesials could make a significant contribution to the overall productiol~o f energy and food from renewable resources. As a consequence, much research cffort has been directed, in recent years, toward inlproving the production of cellulolytic enzymes. While considerable improvements have been made in the productivity of cellulase producing organisms, through st~-ain selection and devclopment, much attention has also been given to iinprove the fermentation process. This is why four agro-industrial by-products of sugar crops (bcet Icavcs, bcet pulp, beet niolasses and cane bagasse) liave been studied for their possible use to produce cellulolytic enzymes by Trichodernzn reesel, - EMCCS71, EMCC872 and EMCC873 stmins in order to select the best strain for their production. In addition, the optimum concentration of enzyme inducing by-products and some other environlnental felmentation conditions for biosynthesis the maxinlum levels of enzymes activity were determined. Part of this work was can-ied out to isolate partially purified eilzyme coinplex with high filter paper and carboxymetl~yl enzyme activity, then testing the hydrolysis efficiency of isolated enzymes for producing glucose using insoluble cellulose as enzyme substrate. However, from the obtained results the following conclusion could be reached: 1. from tlic chemical analysis of the four studicd by-psoducts, i.e. bect Icavcs, bcet pulp, bect nlolasses and cane bagasse the following could be conluded: a. Cane bagasse, beet pulp and beet leaves contained high amount of cellulose (59.1 1, 46.12 and 25.80%, respectively) and, hence could be considered as cellulose iich sources, while beet molasses did not: contain cellulose. b. The highest ratio of cellulose to lignin was recorded with cane bagasse, while the lowest in beet pulp. c. Only beet pulp contained pectin substances (19.22%). d. Beet leaves had the hghest content of crude protein 28.04% and ash 19.65% followed by beet molasses which contained 12.84% and 16.09%, respectively. The lowest contents (3.83% and 2.0296, respectively) were recorded with dried cane bagasse. e. High content of reducing (21.15%) and nonrcducing sugars (47.95%) were found in beet molasses, whereas, cane bagasse had the lowest contents (1.65% and 4.64%, respectively). It could be observed that the best st~ainw llich induced high activity of CMCase and FPase in all tested media was T. reesei EMCC871. While EMCC872 strain produced the lowest activities of both enzymes. EMCC871 strain was selected to carry out all the following research esy criments. The best waste cclllulosic materials as substrate for producing cellulases was beet pulp followed by cane bagasse when added by 1% concentration to thc production medium. The variation of different enzymes activities induced by various by-products may be due to their different contents of chcniical constituents.The optinium concentrations of cellulosic by-product which induced the the highest ccllulolytrc enzymes activities after 7 days of incubation period in culture filtrates of T. reesei EMCC871 were: a. Three percentage of beet leaves produced 32.34 and 33.11 uJ100 ml of CMCase and FPase, respectively. b. One and half percentage of beet pulp produced 46.82 and 5 1.55 u/l00 nd of CMCase and FPase, respectively. c. Thrce percentage of cane bagasse produccd 40.13 and 39.78 ~1101011 1of CMCase and Fase, respectively. 5. Bcct rllolasses had an induction effect when added to media contain 1.5% bcct pulp or 3% cane bagasse, while it had repressing effect when added to beet leaves medium and the following results were obseived: a. Addition of 1% molasses to medium containing 3% beet leaves reduced the biosynthesis of CMCase and FPase activity by about 15.6% and 44.6%, respectively after 8 days of fei~neiltation. b. Addition of 1% nlolasses to medium containing 1.5% beet pulp increased cnzynles biosynthesis by 14.5% for CMCase and by 3 1.3% for FPase. c. Addition of 1% nlolasses to mediunl containing 3% cane bagasse increased e~~zynlbeiso synthesis by 6.1 % and 76.7% for CMCasc and FPase, respectively. d. ’The optiniutn concentmtion of beet molasses that causes the mximum induction of cell~dases biosynthcsis was 1.5% with both media containing bect pulp or cane bagasse. 6. Tlm optimal cnvisoonrnental conditions for.