• Korean Journal of Microbiology
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• v.36 no.1
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• pp.20-25
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• 2000

One of endoglucanases(F-II-II) was purified from the culture filtrate of Trichoderma sp. C-4 through two step procedures including chromatography on Sephacryl S-200 and Sephacryl S-100. The molecular weight of the enzyme was determined to be about 26,000 by SDS-PAGE and the isoelectric point as 8.0 by analytical isoelectric focusing. The optimum temperature of the enzyme was $50^{\circ}C$ and the optimum pH was 5.0. No loss of activity was observed when the enzyme was preincubated at $50^{\circ}C$ for 24 hours. The specific activity of the enzyme toward carboxymethylcellulose (CMC) was estimated to be 776.2 U/mg. The internal amino acid sequence was analysed.

• The Korean Journal of Food And Nutrition
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• v.6 no.3
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• pp.199-207
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• 1993

In order to obtain a good microorganism capable of degrading microcrystaline cellulose (avicel), the screening test was carried out from soil and brown-rot wood. 8 strains which had good avicel-hydrolyzing activity were isolated. Among them, HK 47 which exhibited the highest avicel hydrolyzing activity was identified as Trichoderma sp. HK 47. Maximum avicel-hydrolyzing enzyme production from Trichoderma sp. HK 47 was obtained with the optimum medium contained carboxymethylcellulose 1.5% as carbon source, NaN030.75% as nitrogen source, KH2P040.5%, MgSO4.7H2O 0.1%, Tween 800.005% (V/V) during stationary cultivation at pH 6.0, 3$0^{\circ}C$ In this case, the production of avicel-hydrolyzing enzyme was 0.028 U/ml.

• Journal of Mushroom
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• v.13 no.3
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• pp.256-261
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• 2015

This study was conducted to reduce contamination ratio of oyster mushroom bottle cultivation. The optimal conditions of substrate sterilization for reducing of contamination ratio were at $121^{\circ}C$ for 90 min. In addition, UV-C irradiation is good for lower contamination ratio to continue over 6 hours at cooling and inoculation room after sterilization. The contamination ratio and density of microorganisms of substrate were showed 0% after sterilization at $121^{\circ}C$ for 90 min. Trichoderma sp., main pathogen of mushrooms, was detected from substrate after sterilized during 2 or 4 hours at $101^{\circ}C$ and $105^{\circ}C$, respectively. The amount of electricity used was the lowest at $121^{\circ}C$ for 90 min than that of other sterilization conditions. The UV-C irradiation treatment was used UV-C lamp(40 watts) in the inoculation room($56m^3$). The density of bacteria did not detected after UV-C irradiation for 6 hours. And the death ratio of bacteria and Trichoderma sp. was 99.9% after UV-C irradiation for 6 hours. However, in the same UV-C irradiation time, the death ration of Cladosporium sp. was 90.9%. Therefore, the death ratio of fungi was lower than that of bacteria at the same UV-C irradiation treatment.

• Microbiology and Biotechnology Letters
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• v.4 no.3
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• pp.105-110
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• 1976

In the studies of microbiological utilization of cellulosic wastes, cellulolytic fungi were isolated and screened out. At the first stage, 221 cellulolytic fungi were isolated from different sources such as soils, humus, composts and rotten wood debris by enrichment culture techniques. In the second stage, 36 strains of fungi out of those previously isolated were selected for their cellulase activities estimated by means of filter paper degradation, carboxy methyl cellulose liquefaction and cup method. Activities of C$_1$-cellulase, C$\sub$x/-cellulase and filter paper activity were adopted on the final screening stage and five different strains which are tentatively identified as Aspergillus sp.(strain No. AS-9), Penicillium sp. (strain No. KNI-1-2), Trichoderma, sp. (strain No. KI-7-2, KI-7-5, KI-4-1-1B) were selected for their high potency of C$_1$ and C$\sub$x/-cellulase activities. When rice straw milled and treated with NH$_4$OH was hydrolyzed with the crude enzyme Prepared from the culture broth of Trichoderma sp. (strain No. KI-4-1-1B), saccharification rate was obtained up to 26％.

• Microbiology and Biotechnology Letters
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• v.25 no.4
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• pp.346-353
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• 1997

During the screening of cellulase producing microorganisms, a fungal strain C-4 was selected from etiolated leaves. Based on taxonomic studies, the fungus could be classified as a strain of Trichoderma sp. When the strain C-4 was cultured in Mandels' media at 28$circ$C for 6 days, the enzyme activities detected in broth were as follows: 8.2 U/ml (28.1 U/mg) of CMCase activity, 0.75 U/ml (2.58 U/mg) of Avicelase activity, 1.67 U/ ml (5.68 U/mg) of $eta$-glucosidase activity. The optimum pH for enzyme induction was 6.2. The crude enzyme retained 100% of its original CMCase activity at 50$circ$C for 1 hr (pH 5.0), and at 4$circ$C for 24 hrs (pH 5.0). There was no effect on the CMCase activity in the presence of 1 mM of CsCl, LiCl, MgCl$_{2}$, and FeCl$_{2}$, respectively. When the crude enzyme was treated with trypsin and chymotrypsin (2% W/w) for 10 minutes, the remaining CMCase activity was 70%, but there was no further loss of activity for 60 minutes treatment at 30$circ$C. The crude enzyme showed the synergism with rumen fluid for the hydrolysis of Avicel and CMC by 118% and 130%, respectively.

• Microbiology and Biotechnology Letters
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• v.31 no.1
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• pp.42-45
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• 2003

A Trichoderma sp. SO-571 producing cellulase was isolated from soil, and a pilot-scale cultivation and separation of cellulase were conducted. The cellulase activity was about 14.5 unit/ml after 112 hr of cultivation in a 301 fermenter containing 3.0% cellulose, 4.0% soybean powder, 3.0% wheat bran, 0.5% ($NH_4$)$_2$$SO_4$0.2% urea, 1.0% CSL, 0.5% $KH_2$PO$_4$, and 0.2% Tween 80. The cellulase was purified over 4.6 folds in three steps with 47.86% yield. The optimum pH of cellulase was pH 5.0 and optimum temperature was $60^{\circ}C$. To investigate the effect of the cellulase-treated cellulosic fabric, the weight loss was compared. The weight loss of denim treated with cellulase from Trichoderma sp.SO-571 was 2.9% and that with Celluclast 1.5L was 2.2%. In tencel treatement with enzyme, cellulase showed 0.7% higer weight loss than that with Celluclast 1.5L.

• Microbiology and Biotechnology Letters
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• v.6 no.1
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• pp.1-8
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• 1978

In order to develop the processes for the production of fermented feed from cellulosic agricultural by-product, cereal straw, by th action of cellulolytic fungus, the properties of the cellulolytic enzyme produced by Trichoderma sp. KI 7-2 was studied. A higher enzyme activity was obtained in the culture added by 1％ rice or barley straw powder than in the culture of pure cellulose. The crude enzyme was prepared by precipitating from 20∼60％ saturated ammonium sulphate of the culture supernatant. The optimum conditions for the enzyme reaction were temperature of of 50$^{\circ}C$ and pH 4.2. The crude enzyme was static at 50$^{\circ}C$ for two hours and at pH between 4 and 6. These properties were adopted for the fermented feed production, and several production. Thus, several processes of semisolid culture were devicced to up grade tile fermented feed and to develop into the acceptable quality.

• Korean Journal of Microbiology
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• v.41 no.1
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• pp.81-86
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• 2005

One of the endoglucanases, F-I-III, was purified from the culture filtrate of T. sp. C-4 through procedures including chromatography on Sephacryl S-200, DEAE-Sepharose A-50, and Chromatofocusing on Mono-P (FPLC). The molecular weight of the enzyme was determined to be about 56,000 Da by SDS-PAGE, and pI of 4.9 by analytical isoelectric focusing. F-I-III showed the highest enzyme activity at $55^{\circ}C$, and the pH optimum of the enzyme was 5.0. There was no loss of activity when the enzyme was incubated at $50^{\circ}C$ for 24 hours. The specific activity of the enzyme F-I-III toward the CMC was 315.4 U/mg. The Km value for $PNPG_2$ of F-I-III was 2.69 mM. N-terminal sequence of F-I-III was analyzed to be QPGTSTPEVHPKKLTTYK. It showed $95\%$ of homology to that of EGI from T. reesei. The presence of some metal ions (1 mM) had only a little effect on CMCase activity. The treatment of the reducing agents resulted in the increase of endoglucanase activity.

• Korean Journal of Microbiology
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• v.31 no.2
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• pp.157-165
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• 1993

A 1, 4-.betha.-D-xylanase, designated as xylanase II, was purified from the culture filtrate of Trichoderma koningii ATCC 251131 by column chromatography on Sephadex G-75, SP-Sephadex C-50, DEAE-Sephadex A-50 and Sephadex G-50 with an overall yield of 6.97%. It has a molecular weight of 21.000 and an isoelectric point of 9.4. The enzyme activity is optimal at pH 5.0 and at a temperature of 50.deg.C. Xylanase II is stable up to 50.deg.C, while 40 and 90% of its activity are lost after the incubation for 30 and 60 min at 60.deg.C. The enzyme degrades xylan with relatively high activity, as well as carboxymethylcellulose and Avicel. Its $K_{m}$ values for oat-spelt xylan, larchwood xylan and Avicel are 7.48, 1.98 and 13.33 mg/ml, respectively. The hydrolysis products of oat-spelt xylan by xylanase II are xylose, xylobiose, xylotriose and arabinoxylotriose, while the reaction products of larchwood xylan are xylose, xylobiose, xylotriose and small amount of higher oligomers. The action paterns of the enzyme demonstrate that xylanase II is endo-enzyme.

• The Korean Journal of Mycology
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• v.15 no.2
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• pp.80-86
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• 1987

The author isolated high cellulolytic fungi from natural sources and determined optimal condition of protoplast formation and fusion as fundamental step for improvement of the isolated it's cellulolytic ability. Three different cellulolytic fungi, such as Aspergillus sp., Penicillium sp. and Trichoderma sp., were isolated from soil. Their cellulolytic activities were compared with that of Aspergillus niger which was useful industrially and had cellulase activity. It was Aspergillus sp. that showed the highest activity of all these four fungi. And then it was followed by Penicillium sp., Trichoderma sp., and Aspergillus niger in order. An auxotrophic mutant of Aspergillus sp. was obtained by UV mutagenesis method. Having try to produce protoplast from mycelia, the author found that ${\beta}-glucuronidase$, at pH 6.0, was effective cell-wall lytic enzyme. And the optimal concentration of this enzyme was 5,000 unit/ml. Regeneration rates of wild type, met. auxotroph and arg. auxotroph, in presence of osmotic stabilizer, were 7. 0%, 7. 5% and 5.2%, respectively. PEG with M.W. 6,000 was effective stimulator for protoplast fusion in the concentration of 30% (W IV). In such a condition, we obtained 1.2% cell fusion rate.