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Book The Relative Activity of the Cellulase Enzyme System of Trichoderma Reesei with Native and Modified Cellulosic Substrates

Download or read book The Relative Activity of the Cellulase Enzyme System of Trichoderma Reesei with Native and Modified Cellulosic Substrates written by Ean-Tun Liaw and published by . This book was released on 1994 with total page 302 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book The Cellulolytic Enzyme System of Trichoderma Reesei

Download or read book The Cellulolytic Enzyme System of Trichoderma Reesei written by Tuula T. Teeri and published by . This book was released on 1987 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book American Doctoral Dissertations

Download or read book American Doctoral Dissertations written by and published by . This book was released on 1994 with total page 800 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Trichoderma Reesei Cellulases

Download or read book Trichoderma Reesei Cellulases written by C. P. Kubicek and published by . This book was released on 1990 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt: The proceedings of a symposium on Trichoderma cellulases held at the Technical University of Vienna September 14-16, 1989, attended by 100 scientists representing both academic institutions and industrial research laboratories.

Book Dissertation Abstracts International

Download or read book Dissertation Abstracts International written by and published by . This book was released on 1995 with total page 770 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Trichoderma Reesei Cellulases and Other Hydrolases

Download or read book Trichoderma Reesei Cellulases and Other Hydrolases written by Pirkko Suominen and published by . This book was released on 1993 with total page 324 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Collection of Trichoderma Reesei Cellulase by Foaming

Download or read book Collection of Trichoderma Reesei Cellulase by Foaming written by Qin Zhang and published by . This book was released on 2007 with total page 197 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Facing the current energy crisis, people try to find alternative energy sources. Certain microbes can ferment soluble sugars to ethanol, which is a well known biofuel. Cellulosic biomass is the most abundant renewable resource. Cellulose can be broken down to soluble sugars by the cellulase enzymes produced only by some microbes. The combination of the above two processes, i.e., break-down of cellulose to sugars and conversion of sugars to ethanol, represents a major approach of solving the energy crisis through renewable biological processes. One of the bottle necks of this approach is the relatively high production cost of cellulase. In this research, the main task was to develop a separation process for cellulase using cost-effective and environment-friendly foam-based techniques. First, the foaming properties of the fermentation broth of Trichoderma reesei RUT C-30 were investigated. The experiment results showed that cellulase was not the dominant substance that caused the foaming of the fermentation broth, although the increase of cellulase concentration in the fermentation process appeared to parallel the increase in foaming tendency. Cellulase concentration was found to be only a weakly positive factor contributing to the foaming whereas the presence of cells and solid cellulose powders had negative effects on foaming. The cell wall was found to be hydrophobic according to the study conducted to observe the cells partition between hydrophobic (organic solvent: n-hexadecane) phase and hydrophilic (aqueous) phase. The finding of hydrophobic cell wall was consistent with the observation that the cells would come out with foam in the foaming study. To prevent the cell from being foamed out of the fermentor during the foaming process intended for cellulase collection, the cell immobilization in small (3mm*3mm*3mm) pieces of polyurethane (PU) foams with different porosity and pore size was also investigated. With some of the PU foam materials, the cells could be effectively immobilized and would not be foamed out during the foaming process. Nevertheless, this system did not function well in the typical stir-tank fermentor: the high shear stress present near the tip of the impeller blades appeared to strip the immobilized cells off the PU foam pellets and caused significant subsequent growth of free (not immobilized) cells in the broth. In a subsequent study of cellulase production using cellulose hydrolysate (CH) as the inducing substrate, it was observed that the addition of the hydrolysate resulted in higher enrichment ratios of cellulase concentration in the collected foamate (over the residual concentration in the spent broth). The foaming study was then expanded to include the addition of other cellulase substrates and substrate analogs, such as xylan hydrolysate (XH) and carboxylmethylcellulose (CMC). The results clearly demonstrated the addition of CH, XH and CMC would improve the enrichment and purification of cellulases by foaming. The improvements were attributed to the affinity binding between the substrates/substrate analogs and the cellulase enzymes and the increased partition of the substrate-enzyme complexes to the foam's air-liquid interfaces. To further pursue the above affinity foaming phenomenon for significantly improved collection and, potentially, purification of cellulase, a polymeric foaming agent was designed and synthesized. The polymeric surfactant has two parts, one is the hydrophobic region containing methylmethacrylate (MMA) and methacrylic acid (MAA), the other part is cellobiose, i.e., the substrate of the enzyme to bind with during foaming process. Unfortunately, the foaming ability of this synthetic surfactant was not good enough and its synthesis was complicated. As an easier first step, two glycolipid biosurfactants, sophorolipids and rhamnolipids, were investigated as the possible affinity foaming agents. Both glycolipids had a disaccharide moiety that was expected to bind selectively to the â-glucosidase in cellulase. While sophorolipids did not foam well, rhamnolipids showed great foaming ability and selectivity towards â-glucosidase. The enrichment ratio of â-glucosidase activity in the foamate reached up to 20 in the solutions prepared by cellulase powders (from Sigma). The significant benefits of such affinity foam collection and/or fractionation techniques were clearly shown."--Abstract.

Book Applied and Environmental Microbiology

Download or read book Applied and Environmental Microbiology written by and published by . This book was released on 1991 with total page 1016 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Visual Characterization of the Mode of Action of the Cellulase Enzyme System of the Fungus Trichoderma Reesei

Download or read book Visual Characterization of the Mode of Action of the Cellulase Enzyme System of the Fungus Trichoderma Reesei written by Alan Robert White and published by . This book was released on 1981 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Cellulase Production by Trichoderma Reesei Rut C30

Download or read book Cellulase Production by Trichoderma Reesei Rut C30 written by Chi-Ming Lo and published by . This book was released on 2008 with total page 223 pages. Available in PDF, EPUB and Kindle. Book excerpt: As the price of oil continues to increase and the concern over global warming heightens, finding alternative renewable sources of energy becomes more and more imperative. Considering the abundance of lignocellulosic biomass, the potential significance of its conversion to fuel such as ethanol has long been recognized. Ethanol production from lignocellulosic biomass requires the breakdown of the solid material to simple sugars that can be consumed by microorganisms. The breakdown of lignocelluloses includes the important step of hydrolyzing cellulose, which are [Beta]-1, 4 linked polymers of glucose, by a group of enzymes collectively termed cellulase. The cost of cellulase production profoundly influences the economics of the entire ethanol production process. Trichoderma reesei Rut C-30 is the most commonly used fungal strain for industrial cellulase production. With an overall goal of decreasing the cellulase production cost, this thesis work was focused on two topics: (1) investigation of the performance of different cellulase-inducing substrates in T. reesei Rut C-30 fermentation and (2) development of a more advanced model to describe the culture behaviors of T. reesei Rut C-30 grown on lactose-based media. The cellulase-inducing substrates investigated in this work included the acid-treated hydrolysate, lactose, and the sophorolipids produced by the yeast Candida bombicola. In addition to the above focused topics, the effects of culture conditions on cellulase production were also investigated. The acid-treated hardwood hydrolysates used in the study were prepared by a two-stage process, with different durations of boiling and acid concentrations. The results indicated that the inducing ability of the hydrolysates decreased with increasing boiling time (less oligomers). The observation was attributed to the lower amounts of inducing oligomers remaining after the longer boiling in acid. When compared with cultures growing on mixed carbon substrates of cellulose and glucose, the culture growing on hydrolysates showed a longer lag phase of about 24 hours (before the active cell growth began), but produced adequately comparable final cellulase activity. The study with lactose as an inducing substrate was conducted in both batch and continuous culture systems with lactose and other relevant substrates (glycerol, glucose and galactose) as the carbon source. Instead of direct ingestion, lactose is believed to be hydrolyzed by extracellular enzymes to glucose and galactose, which are then taken up by the cells. The study results indicated that glucose strongly represses the galactose metabolism: Cells started to consume galactose only after the glucose had been depleted. A mathematical model incorporating all important metabolic activities was developed to describe the culture behaviors. All of the experimental results obtained were used in model fitting to generate a set of best-fit model parameters. The study provided significant conceptual and quantitative insights to the lactose metabolism and cellulase production by T. reesei Rut C-30. This study was also the first to hypothesize and demonstrate the use of sophorolipids as the inducing substrate for cellulase production. A unique process for cellulase production using a mixed culture of T. reesei Rut C30 and Candida Bombicola growing on glycerol-based media was investigated. Hypothetically, the sophorolipids produced by C. bombicola were hydrolyzed to form sophorose, which then served as the inducer for cellulase production by T. reesei. Further study to optimize the sophorolipid-induced cellulase production process is recommended.

Book Adsorption and Synergism of Cellulases During Hydrolysis of Cellulosic Materials

Download or read book Adsorption and Synergism of Cellulases During Hydrolysis of Cellulosic Materials written by Hanshu Ding and published by . This book was released on 2000 with total page 348 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book A Filter Paper Assay for Low Cellulase Activities and the Cultivation of Trichoderma Reesei on Acid Whey and Sweet Whey Permeate

Download or read book A Filter Paper Assay for Low Cellulase Activities and the Cultivation of Trichoderma Reesei on Acid Whey and Sweet Whey Permeate written by Tor Soren Nordmark and published by . This book was released on 1993 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt: The traditional filter paper assay for saccharifying cellulase originally described by M. Mandels et al (1976) has been modified to make possible low activity determinations of Trichoderma cellulases. The enzymatic activity appears to decline during a prolonged incubation period if no precautions have been taken. By means of adding bovine serum albumin and potassium chloride as protein stabilizers and sodium azide as an antimicrobial agent filter paper activities in the range from 0.02 to 0.37 (IUPAC assay, 1987) can be estimated by extending the incubation time up to 20 hours. Filter paper activity values obtained by this method may be compared to those obtained by the IUPAC assay by using a conversion factor from 1.4 to 1.7. Acid whey and sweet whey permeate have been investigated as media for growth and metabolite production by Trichoderma reesei QM 9414 using shake flask cultures and spore inocula. In the case of acid whey the mycelial growth after 2 weeks is 13 mg dry weight /ml substrate. The specific growth rate is 0.29/day. The fungus appears to metabolize the whey protein the first 2 weeks. The alkalinity of acid whey rises continuously over a three week period up to a pH of 8.5. In the case of whey permeate the maximal mycelial weight gain is 4.4 mg/ml which appears after 8 days. A rise in net soluble protein level comes after 3-5 days and reaches a maximum value of 0.23 mg/ml after 2 weeks. The pH of whey permeate rises continuously to 7.5 after 3 days and then slowly declines. The net production of cellulases is low on both media. Dilution 1:6 of the acid whey, supplementation with ammonium sulfate and pHadjustments did not enhance the production of cellulases. Acid whey supports a significant growth and sweet whey permeate shows potential for extracellular protein production. A literature review surveys the composition and uses of acid whey, environmental aspects of whey wastes, the fungus Trichoderma reesei, the mode of action of the Trichoderma reesei cellulase system and the structure of cellulose in cotton and wood.

Book Study of the Production of Cellulases with Trichoderma Reesei and Investigation of the Enzymatic Hydrolysis of Cellulosic Substrates

Download or read book Study of the Production of Cellulases with Trichoderma Reesei and Investigation of the Enzymatic Hydrolysis of Cellulosic Substrates written by Roberto Leyva and published by . This book was released on 1984 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Approaches to Enhance Industrial Production of Fungal Cellulases

Download or read book Approaches to Enhance Industrial Production of Fungal Cellulases written by Manish Srivastava and published by Springer. This book was released on 2019-04-26 with total page 218 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cellulase is a key enzyme of industrial interest and plays a crucial role in the hydrolysis of cellulose, a prime component of plant cell walls. Cellulase covers a broad area in the global market of industrially important enzymes and it is considered as the third largest industrial enzyme globally. Additionally, cellulase contributes about 20% of the total enzyme market globally because of its massive demand in various industries such as in biofuel production, pulp, paper, textile, food, and beverages, as well as in detergent industries. Among these, the demand of cellulase may become frequently selected in the commercial production of biofuels in the future and thus will further increase demand of cellulase in the biofuel industry. Because biofuel production is still not realized in a cost-effective, practical implementation due to its high cost (the higher cost of biofuels is due to higher production costs of enzymes), there is a need to introduce these types of approaches, which will help to lower the cost of enzyme production for developing overall economic biofuel production.

Book

    Book Details:
  • Author : עמיחי פרימן
  • Publisher : Open University of Israel
  • Release : 1998
  • ISBN : 9789650604486
  • Pages : 286 pages

Download or read book written by עמיחי פרימן and published by Open University of Israel. This book was released on 1998 with total page 286 pages. Available in PDF, EPUB and Kindle. Book excerpt: יחידה 1: ביוקטליזה: טכנולוגיה אנזימית.-- יחידה 2: מיקרוביולוגיה יישומית.-- יחידה 3: יישומים ביוטכנולוגיים של הנדסה גנטית.-- יחידה 4: נוגדנים ושימושיהם.-- יחידה 5: תרביות תאים.-- יחידה 6: ביוטכנולוגיה סביבתית.