• Korean Journal of Human Ecology
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• v.2 no.1
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• pp.142-148
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• 1999

Tencel fabrics were treated with cellulase after mechanical prefibrillation treatment. SEM analysis was carried out to study morphological change of the treated fabric. The cellulase-treated Tencel fabrics were evaluated for weight loss and tensile strength. X-ray diffraction method, moisture regain, and K/S value were used to elucidate crystalline structural changes occurred by cellulase treatment. Degree of polymerization and copper number of the cellulase-treated fabrics were also measured to estimate effect of hydrolysis. SEM analysis indicated that with treatment of prefibrillation and cellulase, fibrils were produced and damage occurred deep into the fiber. Increases in concentration and time of cellulase treatment increased weight loss and decreased tensile strength retention of the treated fabrics. As cellulase hydrolysis progressed, degree of crystallinity, moisture regain and K/S value were not much changed. (Korean J Human Ecology 2(1) : 142∼148, 1999)

• Journal of the Korean Society of Clothing and Textiles
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• v.25 no.1
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• pp.144-153
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• 2001

The effect of crosslinking on hand of the cellulase treated Tencel fabrics was investigated. Tencel fabrics were crosslinked with DMDHEU, mechanically prefibrillated, hydrolyzed by cellulase, and treated with softener. The treated fabrics were characterized by add-on, weight loss, DP rating, WRA, strength, SEM analysis and hand measurement. As DMDHEU concentration increased, weight loss of DMDHEU/cellulase treated fabrics decreased. However, cellulase treatment decreased DP properties and strength retention. Less fibrils were observed in the cellulase treated fabrics after DMDHEU treatment than the cellulase treated ones. It was confirmed that crosslinking with DMDHEU treatment was effective to control fibrillation. At 5% of DMDHEU concentration, DMDHEU/cellulase treated fabrics showed softer, smoother and bulkier hand compared with other treated fabrics. Among mechanical properties, bending and shearing properties were decreased progressively through DMDHEU, cellulase, and softener treatment. DMDHEU treatment contributed to impart resilience, cellulase treatment to bulkiness and softener treatment to smoothness. As the treatment of DMDHEU, cellulase, and softener progressed NUMREI, FUKURAMI, and THV increased with the exception of KOSHI.

• 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.

• Asian-Australasian Journal of Animal Sciences
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• v.10 no.6
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• pp.575-580
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• 1997

Two experiments were carried out to evaluate the effects of cellulase and brewers' grains addition on improvement of the fermentation quality and the nutritive value of barley straw silages made from dried or fresh straw. In Exp. I : 1 kg dried barley straw + 2 kg wet brewers' grains + 0 (I-0), 2 (I-2), 4 (I-4), 6 (I-6), and 8 (I-8) g of cellulase. In Exp. II : 2 kg fresh barley straw + 2 kg wet brewers' grains + 0 (II-0), 2 (II-2), 4 (II-4), 6 (II-6), and 8 (II-8) g of cellulase. Each prepared material was ensiled into vinyl bag silos (5 L capacity) and stored for 10 (Exp. I) or 7 (Exp. II) months at $21^{\circ}C$. The fermentation quality and nutritive value of barley straw silages produced were markedly improved by mixing them with wet brewers' grains, on the other hand the effect of cellulase addition on the fermentation and reduction of the cell wall components in the silos at ensiling more effectively occurred at low dry matter silages rather than at the high ones. All silages in both Exp. I and II were found well preserved as indicated by their low pH and high lactic acid concentration. Cellulase treated silages had a lower pH (p<0.05) and a higher lactic acid concentration (p<0.05) than those of without cellulase addition. NDF, ADF, and (Hemi)cellulose contents of cellulase treated silages reduced (p<0.05) compare to those of the corresponding silage without cellulase. Increasing levels of cellulase addition caused an increase in fermentation quality and reduction of cell wall components. In vitro dry mater digestibility was found similar in all silages. Fermentation quality and nutritive value of barley straw silages were improved by both wet brewers' grains and cellulase addition. Cellulase addition reduced the cell wall components silages, but did not improve the digestibility.

• Korean Journal of Microbiology
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• v.45 no.3
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• pp.257-262
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• 2009

Carboxymethyl celluase (cellulase) was purified from cell-free extract of the recombinant Escherichia coli carrying a Bacillus licheniformis WL-12 cellulase gene by DEAE-Sepharose and phenyl-Sepharose column chromatography with specific activity of 163 U/mg protein. The molecular mass of the purified enzyme was estimated to be approximately 49.5 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The enzyme had a pH optimum at 5.5 and a temperature optimum at $55^{\circ}C$. The activity of the enzyme was completely inhibited by SDS (5 mM), and slightly enhanced by $Cu^{2+}$ (5 mM). The cellulase was active on CMC, konjac, barely glucan and lichenan, while it did not exhibit activity towards xylan, locust bean gum, and p-nitrophenyl-$\beta$-glucopyranoside. The predominant products resulting from the cellulase hydrolysis were cellobiose and cellotriose for cellooligosaccharides including cellotriose, cellotetraose and cellopentaose. The enzyme could hydrolyze cellooligosaccharides larger than cellobiose.

• Journal of the Korean Wood Science and Technology
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• v.17 no.3
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• pp.45-51
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• 1989

A major problem in the enzymatic hydrolysis of lignocellulosic substrates is the very strong bonding of cellulase to lignin and even cellulose in the hydrolysis residues. This phenomenon inhibits recycle of the cellulase which is a major expense of the enzymatic hydrolysis process. In this paper, autohydrolyzed wood was delignified by two-stage with a 0.3% Na OH extraction and oxygen-alkali bleaching and was subjected to enzymatic hydrolysis with cellulase. Also, an improved almost quantitative recycle process of cellulase enzyme was discussed. In enzyme recovery by affinity method. the first recycling showed relatively high hydrolysis rate of 97.4%. Even at the third recycle. hydrolysis rate was 86.7 percents. In the case of cellulase recovery by ultrafiltration method, first 2 recycling treatments resulted very high hydrolysis rate(97.0-97.7%). Even the third recycling showed about 94.2%. Authoydrolysis of oak wood followed by 2-stage delignification with alkali and oxygen-alkali produced a substrate for enzymatic hydrolysis that allowed almost quantitative recycle of cellulase.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1977.10a
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• pp.195.1-195
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• 1977

Cellulase 분비 균주인 Trichoderma viride의 cellulase 생산능력이 높은 변이주를 선별, 분러하기 위하여 cellulose 기질이 첨가된 Plate상에서 작은 단일 colony를 형성시키고 분비된 cellulase가 배지내의 cellulase를 분해하여 생긴 clear zone을 육안으로 관찰함로써 cellulase생성 조절변이주 혹은 효소역가가 높은 균주를 식별할 수 있는 방법을 개발하였다.(중략)

• Journal of Microbiology and Biotechnology
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• v.9 no.1
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• pp.44-49
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• 1999

Cellulase production by fed-batch cultivation of Trichoderma reesei Rut C30 with various initial concentrations of Solka Floc in 1 % wheat bran-containing medium was investigated. The cellulase activity and productivity increased with initial Solka Floc concentration up to 5%. When a total Solka Floc concentration of 90 g/l was used for cellulase production, CMC (carboxymethyl cellulose) and FP (filter paper) activities, productivity, and yield were 359.7 U/ml, 30.61 U/ml, 161 FPU $L^{-1}$ $h^{-1}$, and 340 FPU $g^{-1}$, respectively. It was important to maintain a high cell concentration during cellulase production to obtain high cellulase activity and productivity. Cellulase powder was prepared by ammonium sulfate precipitation: FP activity was 396.7 U/g and CMC activity was 6481 U/g.

• Microbiology and Biotechnology Letters
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• v.6 no.3
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• pp.129-133
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• 1978

A plating technique was devised to screen for high producing cellulase mutants of Trichoderma viride. The method employs: 1) The use of deoxycholate to limit colony size and 2) saponin to enhance cellulase detection in combiantion with rice straw pulp and pure cellulose on agar plate. The method will be used to isolate constitutive cellulase mutants of Trichoderma viride and should prove useful for isolating high producing mutants from a range of organisms.

• Korean Journal of Food Science and Technology
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• v.54 no.4
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• pp.422-430
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• 2022

The effects of phytase and cellulase treatment on the bioavailability of iron, calcium, and zinc in whole wheat flour and their food applications were evaluated in this study. Whole wheat flour was treated with phytase and cellulase either individually or in combination and incubated at 50℃ for 2 h; the concentrations used for the individual enzymes were 2%, 10%, and 20%. The concentration of the combination enzyme was 20% with a mixing ratio of 5:5. Total dietary fiber and phytate contents were reduced as the concentrations of phytase and cellulase increased. The bioavailability of iron, calcium, and zinc was notably improved after in vitro digestion in 20% cellulase, combination enzyme, and 20% phytase, respectively. Muffins made with cellulase- and phytase-treated whole wheat flour showed improved quality and bioavailability of minerals. Phytase- and cellulase-treated whole wheat flour may be useful for development of functional food products with improved bioavailability of minerals.