绿色木霉ZY-1固态发酵产纤维素酶

利用筛选的绿色木霉ZY-1（Trichoderma viride ZY-1）固态发酵产纤维素酶,采用稻草和麸皮为底物,考察稻草与麸皮比例随发酵时间对产酶的影响。结果表明：底物中,在m（稻草）：m（麸皮）为0：5和1：4时,发酵48h,pH保持4．5左右,还原糖量急剧上升,胞外蛋白产量最低;仅以稻草作底物时,整个发酵过程中pH约为7,还原糖量最低,胞外蛋白产量较高而滤纸酶活、羧甲基纤维素酶（CMCase）和β-葡萄糖苷酶（β-Gase）酶活均较低;在m（稻草）：m（麸皮）为3：2时,发酵96h,滤纸酶活达最大值5．01U／g干曲;m（稻草）：m（麸皮）为1：4时,发酵96h,β-Gase酶活达最大值4．6U／g干曲;m（稻草）：m（麸皮）为4：1时,发酵72h,CMCase酶活达最大值6．01U／g干曲。因此,底物中存在适量的稻草和麸皮有利于Trichoderma viride ZY—1产纤维素酶。     

Enhanced Cellulase Production by a Mutant of Trichoderma viride

A mutant strain that secretes twice as much cellulase as its parent was obtained by irradiating conidia of Trichoderma viride QM 6a with a linear accelerator.     

pH控制下绿色木霉(Trichoderma viride)流加发酵生产纤维素酶

绿色木霉（Trichodermaviride）在pH控制发酵条件下,采用流加葡萄糖发酵策略,可显著提高综合滤纸酶活力（FPA）和内切酶（endo—β—1,4-glucanase,EG）、外切酶exo—β-1,4-glucanase,CBH）、纤维二糖酶（cellobiase,CB）酶活。在5L发酵罐中采用pH控制和流加葡萄糖工艺,可提高CB酶含量,改变酶组分之间的比例,使得FPA、EG、CB和CBH酶活分别达到50．0U／mL,210．0U／mL,4．0U／mL和2．5U／mL,比摇瓶发酵分别提高了6．7．4．2、19、2．5倍。     

Degradation of Cellulosic Materials by Trichoderma viride Cellulase

The extra-cellular filtrates of Trichoderma viride ITCC–1433 showed considerable cellulolytic activity against native celluloses, cellulose derivatives and raw materials. Newspaper-yellow and the rice straw were the prominent waste materials which were preferentially attacked by the enzyme. The alkali treatment of the latter doubled the sugar formation from it. As a result of cellulase action 80.4 per cent of the MN-Cellulose and 60.4 per cent of the alkali treated rice straw lost weight in 96 and 48 hr respectively. The weight loss was more or less equivalent to the reducing sugars formed.     

Cellulase Production by Trichoderma viride on Feedlot Waste

Feedlot waste contains essentially all the necessary nutrients for batch fermentation with the fungus Trichoderma viride. The organism utilizes two-thirds of the carbohydrate in feedlot waste while elaborating cellulase in quantities comparable to commercial preparations. Essentially odor-free, the fermented waste contains all of the original nitrogen but has 24% less organic matter.     

Effect of Cultural Conditions on Cellulase Formation by Trichoderma viride

In order to have increased extracellular production of cellulase by Trichoderma viride ITCC 1433, the organism was grown on various growth factors. Cellulose Powder ?123 was found to be the best C-source while amongst raw materials, alkali-treated rice straw gave the best yield. A combination of peptone, urea and ammonium sulphate gave better production of cellulase than when a single nitrogen source was used. Sugars when added into the cellulose medium, generally suppressed the yield. When the organism was grown on sugars as the sole source of carbon, only lactose and maltose induced any cellulase production. Acetate and ascorbate were conspicuous in increasing cellulase production and when given together they had a cummulative effect and the yeild was doubled.     

Formation of conjugates from ciprofloxacin and norfloxacin in cultures of Trichoderma viride

The formation of conjugates from two antibacterial fluoroquinolone drugs, ciprofloxacin and norfloxacin, was observed in cultures of Trichoderma viride that had been grown in sucrose-peptone broth and extracted 16 d after dosing with the drugs. Both conjugates were purified by high-performance liquid chromatography and found to be optically active. They were identified by mass and proton nuclear magnetic resonance spectra as 4-hydroxy-3-oxo-4-vinylcyclopent-1-enyl ciprofloxacin and 4-hydroxy-3-oxo-4-vinylcyclopent-1-enyl norfloxacin. The transformation of veterinary fluoroquinolones in the presence of fungi may have ecological significance.     

Biomass production from Trichoderma viride in nonconventional oat medium

Oatmeal, an alternative, renewable, and low‐cost substrate, was used for the production of Trichoderma viride spores by submerged fermentation. The nonconventional oat medium was only supplemented with potato peptone, which is a green source of nitrogen for the microorganism. Because particles are suspended in the nonconventional oat medium, the characterization was based on viscosity, average particle diameter, size distribution, and porosity of the particles. Because of the complexity of the fungal biomass extraction, the dry weight and protein content were used as methods for quantifying the growth of T. viride. The inversion between the proportion of mycelia and spores was captured in the microscopic image analysis during the fermentation process. After 60 h, spores began to appear, accounting for most of the form present at 120 h of fermentation. The decrease in pH and the increase in glucose concentration during fermentation indicate that glucan hydrolysis occurs and that glucose is released into the medium. The potential for industrial applications of submerged fermentation with oats for biomass production of T. viride is noted in the results. This simple and easily controllable process has several advantages, including the use of low‐cost substrates for the propagation of a microorganism that is widely used in scientific and commercial settings. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2012     

Semiquantitative Plate Assay for Determination of Cellulase Production by Trichoderma viride

A plate clearing assay was devised to screen for high-producing cellulase mutants of Trichoderma viride. The method employs (i) the use of either rose bengal or oxgall to limit colony size and (ii) Phosfon D (tributyl-2, 4-dichloroben-zylphosphonium chloride) to enhance cellulase detection, in combination with acid-swollen cellulose on agar plates. The method was used to isolate constitutive cellulase mutants of T. viride and should prove useful for isolating high-producing mutants from a range of organisms. This technique has been also used to determine the concentration at which glucose and glycerol inhibit cellulase synthesis by catabolite repression in the wild-type strains.     

Production of cellulase and protein from barley straw by Trichoderma viride

The cellulase production by two strains of the cellulolytic fungus Trichoderma viride was examined. The fungi were grown on different preparations of barley straw pretreated with NaOH under high pressure. The production of cellulases and microbial protein by the better strain (QM 9123) was investigated in an aerated 5-liter fermenter under varying stirring rates (200-350 rpm) and straw concentrations (1–2%). The pH was kept between 3.5 and 4.5. The growth of the fungus was followed by measuring the quantity of CO₂ produced and the cell protein. After 2–6 days growth ceased, the lag phases lasting 0–2 days, increasing with increasing straw concentrations. The maximum enzyme yields were reached after 4–10 days. The protein content of the product was 21–26% and up to 70% of the straw was utilized. The yield constants were calculated to be 0.40–0.56; of the same order as those which can be obtained by growing the fungus on glucose.     

Molecular action of tricholin, a ribosome-inactivating protein isolated from Trichoderma viride

An extracellular protein was isolated from a species of soil-borne fungi (Trichoderma viride) and its amino acid composition has been determined. The protein is acidic with a molecular mass of 14,200 daltons and is given the trivial name tricholin. Tricholin is a potent inhibitor of cell-free protein synthesis. When rabbit reticulocyte lysate was incubated with tricholin at a concentration of 6.3 x 10(-7) M, it completely abolished the capacity of the lysate to support protein synthesis. The inhibition appears to be due to its reaction to ribosomes, since it generates a specific cleavage product, an alpha-sarcin RNA fragment, from reticulocyte ribosomal RNA. This reaction to ribosomes mimics that of alpha-sarcin. The antibody of alpha-sarcin strongly cross-reacts with tricholin, while the antibody of tricholin shows a weak reaction with alpha-sarcin.     

Low-molecular-weight xylanase from Trichoderma viride

An endo-1,4-beta-xylanase (1,4-beta-D-xylan xylanohydrolase, EC 3.2.1.8) has been isolated from a commercial preparation of Trichoderma viride. The molecular weight was 22,000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and the pI value was 9.3. The xylanase was a true xylanase without cellulase activity. When the N-terminal amino acid sequence of the first 50 residues was compared with that of a xylanase from Schizophyllum commune, strong evidence for homology was found, with more than 50% amino acid identity. T. viride xylanase also possessed extensive identity with a proposed amino-terminal consensus sequence of xylanases from bacteria.     

Evaluation of Solid Substrates for the Biosynthesis of Cellulase by Trichoderma viride

A series of 4-alkylthio-1,2-dithiolanes were synthesized from S,S′-(2-alkylthiotrimethylene) di(benzenethiosulfonates), and their biological activities were tested on Culex pipience molestus, Laodelphax striatellus and Tetranychus urticae. These compounds showed potent activity against both insect species, the strongest being displayed by 4-ethylthio-1,2-dithiolane and 4-isopropylthio-1,2-dithiolane.     

绿色木霉JFY-14产纤维素酶的产酶条件研究

利用实验室现有的纤维素酶高产菌株制备纤维素酶。考察了JFY-14菌株产酶培养过程中pH值、培养时间、氮源等条件的影响。得到了最佳产纤维素酶条件:培养时间为72~75 h,初始pH值为4.5~5.0以及最佳培养氮源为1%的硫酸铵。     

Low-molecular-weight xylanase from Trichoderma viride.

An endo-1,4-beta-xylanase (1,4-beta-D-xylan xylanohydrolase, EC 3.2.1.8) has been isolated from a commercial preparation of Trichoderma viride. The molecular weight was 22,000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and the pI value was 9.3. The xylanase was a true xylanase without cellulase activity. When the N-terminal amino acid sequence of the first 50 residues was compared with that of a xylanase from Schizophyllum commune, strong evidence for homology was found, with more than 50% amino acid identity. T. viride xylanase also possessed extensive identity with a proposed amino-terminal consensus sequence of xylanases from bacteria.     

Specific and nonspecific glucanases from Trichoderma viride

Six endoglucanases (Endo I, II, III, IV, V, and VI), three exoglucanases (Exo I, II, and III), and a beta-glucosidase (beta-gluc I) isolated from a commercial cellulase preparation of Trichoderma viride origin were examined as to their activities on xylan ex oat spelts. Endo I, II, and III as well as Exo II and III showed no activity toward xylan and were classified as specific glucanases. Less specificity was found for the endoglucanases Endo IV, V, and VI, Exo I, and beta-gluc I, whose enzymes were able to hydrolyze xylan. With respect to product formation these xylanolytic cellulases fit the classification of xylanases generally accepted in the literature. Kinetic experiment with xylan, CM-cellulose, and p-nitrophenyl-beta-D-glucoside revealed that Endo IV, V, an VI and Exo I prefer to hydrolyze beta-1, 4-D-glucosidic linkages. beta-Gluc I showed no clear substrate preference.     

Transcellobiosylation Reactions Catalyzed by Different Exoglucanase Components of a Trichoderma viride Cellulase in Aqueous Organic Solvent

The contribution of three exoglucanases from a commercial Trichoderma viride cellulase to transcellobiosylation, and the tolerance of these enzymes to acetonitrile co-solvent were studied. The enzymatic reactions were performed with p-nitrophenyl-β-d-cellobioside as the starting substrate. Among these enzymes, the least anionic exoglucanase (Exo I) showed the highest transcellobiosylation activity and acetonitrile tolerance. Exo I retained considerable activity even in 30% MeCN/water and produced p-nitrophenyl-β-d-cellotetraoside at about 1.5% conversion from the initial substrate in 30% MeCN/water. The residual activity of Exo I after incubation in MeCN/water mixture was almost identical to that of the crude cellulase and a considerable amount of the transcellobiosylation properties of the crude cellulase seemed to be attributable to this Exo I component.