• The Korean Journal of Mycology
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• v.12 no.2
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• pp.59-64
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• 1984

The effects of cultural conditions in the rice straw media for cellulolytic enzymes production by Pleurotus sajor-caju were investigated. The optimum moisture content, pH and temperature for enzymes production were 60%, 7.0 and $35^{\circ}C$ in $C_1-cellulase$, and 60%, 5.0 and $25^{\circ}C$ in $C_x-cellulase$, and 60%, 7.0 and $20^{\circ}C$ in ${\beta}-glucosidase$, respectively. When light was irradiated during the cultivation period, $C_1-cellulase$ and ${\beta}-glucosidase$ production were decreased but $C_x-cellulase$ production increased at $500{\sim}1,000\;lux$. During the cultivation period, $C_1-cellulase$ production was contrary to $C_x-cellulase$ and ${\beta}-glucosidase$. Among the various materials added, rice bran was effective to $C_1-cellulase$ production, cotton seed cake and rice bran to $C_x-cellulase$ production, and defatted soybean and fish meal to ${\beta}-glucosidase$ production. The optimum concentration of rice bran for enzymes production were 20% in $C_{1-}$, $C_x-cellulase$ and 10% in ${\beta}-glucosidase$.

• Korean Journal of Pharmacognosy
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• v.7 no.2
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• pp.85-93
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• 1976

Since cellulose is the only organic material that is annually replenishable in very large quantities, we must explore ways to utilize it as a source of energy, food and chemicals. For the utilization of this resource, it is first enzymatic hydrolyzed to glucose, then the glucose can be used as a food, converted single cell protein by microorganism, fermented to clean burning fuel and other chemicals. Cellulolytic enzyme, cellulase, consists of two or three major components, $C_1-cellulase$, $C_x-cellulase$ and ${\beta}-glucosidase$. $C_x-cellulase$ are fairly common but $C_1-cellulase$ are quite rare. Trichoderma viride is the best source of active cellulose, especially $C_1-enzyme$. Saccharification rate of cellulose in greatly influenced by the degree of crystallinity and extent of lignification. But by the pretreatment the substrate with cellulose swelling agent, delignifying reagent and physical treatment, the degree of saccharification is enhanced. Thus, glucose syrups of 2 to 10% concentration are realized from milled newspaper. The enzymatic hydrolysis of such energy rich material, such as cellulose, to glucose is technically feasible and practically achievable on a very large scale.

• Korean Journal Plant Pathology
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• v.13 no.3
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• pp.172-178
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• 1997

Xanthmonas campestris pv. campestris, causal agent of Black rot of crucifers, were isolated and identified from crucifer host. In order to determine the characters of X. c. pv. campestris associated with pathogenicity, Tn5 mutagenesis was carried out by conjugating with E. coli pJB4J1. Transconjugants were plate- assayed for missing cellulase, protease and amylase activity. A cellulase negative mutant was selected and tested for pathogenicity. Light microscopy and Scanning electron microscopy revealed that substomatal tissues were colonized by mutant, but was far less extensive than those by wild type. Stomatal surface and substomatal tissue appeared to have degraded by only wild type in 24 hrs and progression of pathogenesis was distinct in 48 hrs. In 6 days, wild type proliferated well in the tissue facilitated by cellulase activity. As a result, cellulase was determined as the important factor in pathogenesis.

• Korean Journal of Microbiology
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• v.23 no.1
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• pp.25-33
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• 1985

The cell-free cellulolytic enzyme was separated into 3 different enzyme proteins by gel-filtration and ion-exchange chromatography. These fractions were named enzyme A, enzyme B and enzyme C. The mode of action of each of the separated enzymes on crystalline cellulose was examined using infrared spectroscopy and X-ray crystallography. It was concluded that enzyme B is of the $C_1-type$ and reduces the crystallinity of the subatrate by generation an unstable glucopyranose ring structure, whilst enzymes A and C are of the $C_x-type$ and hydrolyse the reaction product of enzyme B to constituent sugars. A reaction scheme for this cellulase system is proposed and discussed.

• 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％.

• Korean Journal of Microbiology
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• v.25 no.4
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• pp.293-303
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• 1987

A $C_{1}$ enriched cellulase fraction was separated from culture filtrate of anaerobic Clostridium thermocellum by hydroxyapatite column chromatography. The separated fraction showed strong synergistic action with $C_{x}$ component (endo-$\beta$-1, 4-glucanase) in digestion of crystalline cellulose, similar to the other aerobic cellulolytic microorganisms. Unlike the $C_{x}$ component the $C_{1}$ enriched fraction was rapidly inactivated by oxidation at the atmospheric condition. The enzyme activity was significantly enhanced by the addition of reducing agents, especially $\beta$-mercaptoethanol, which indicates that a $C_{1}$ component has a lot of sulfhydryl groups essential for the enzyme activity. The effect of metal ions on $C_{1}$ activity was also investigated. The $C_{1}$ fraction was found to be thermally stable compare to endo-$\beta$-1,4-glucanase. Optimal temperature and pH were found to be $60^{\circ}C$ and 6.0, respectively.

• Korean Journal of Microbiology
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• v.25 no.4
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• pp.297-297
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• 1987

A $C_{1}$ enriched cellulase fraction was separated from culture filtrate of anaerobic Clostridium thermocellum by hydroxyapatite column chromatography. The separated fraction showed strong synergistic action with $C_{x}$ component (endo-$\beta$-1, 4-glucanase) in digestion of crystalline cellulose, similar to the other aerobic cellulolytic microorganisms. Unlike the $C_{x}$ component the $C_{1}$ enriched fraction was rapidly inactivated by oxidation at the atmospheric condition. The enzyme activity was significantly enhanced by the addition of reducing agents, especially $\beta$-mercaptoethanol, which indicates that a $C_{1}$ component has a lot of sulfhydryl groups essential for the enzyme activity. The effect of metal ions on $C_{1}$ activity was also investigated. The $C_{1}$ fraction was found to be thermally stable compare to endo-$\beta$-1,4-glucanase. Optimal temperature and pH were found to be 60.deg.C and 6.0, respectively.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.30 no.2
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• pp.13-23
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• 1998

Two major cellulase components purified with sephadex G-75 and DEAE sepharose were applied to bleached kraft pulp to inverstigate the change of fiber properties. Cellulose viscosity was very sensitive to $C_x$ component treatment (more than 15% drop was observed) while being little influenced by $C_1$, component (only 2% drop). Fiber fraction longer than 2mm was reduced by $C_x$ treatment while short fiber fraction was increased greatly by more than 15%. There was little change in fiber length distribution by combined treatment of $C_1$ 1 and $C_x$ at equal. In this case, fine contents increased by more than 2.5% at equivalent refining time. WRV and Density were increased as the amount of $C_1$ or $C_x$ treatment was increased. $C_{x}$ was main cause for increasing them. But the effect fell as enzyme dosage.

• Fashion & Textile Research Journal
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• v.11 no.3
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• pp.469-473
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• 2009

Recently, eco-friendly processing has been focused in the textile industry in order to reduce environmental pollutions. Applications of enzyme technology to the textile industry are an example of more environmentally compatible processes. However, there is not enough quantity of referring to denim fabric subjected to enzymatic treatment. In this study, depending on pH, temperature, cellulase concentration, and treatment time, the weight loss of denim fabrics was examined. Characteristics of enzyme-treated fabrics were measured by tearing strength, stiffness, and K/S values. The effect of a non-ionic surfactant (Triton X-100) on characteristics of the enzyme-treated fabrics was evaluated. The cellulase treatment condition on the cotton fabric were optimized to pH 6.0, $50^{\circ}C$, 1%(o.w.f.), and 60minutes. Characteristics of denim fabrics by cellulase treatment in the presence of Triton X-100 did not improve because Triton-X inhibited the activity of enzyme.

• Fashion & Textile Research Journal
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• v.11 no.3
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• pp.465-468
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• 2009

In this study, acid cellulase was used to treat denim fabrics by varying pH, temperature, enzyme concentration, treatment time and non-ionic surfactant (Triton X-100) concentration. Treatment condition was controlled based on the weight loss. The characteristics of enzyme-treated fabrics were measured in terms of tearing strength, stiffness, and color difference. The optimum conditions for cellulase treatment of denim fabric were pH 5.0, $50^{\circ}C$, 3% (o.w.f.), 90minutes. The weight loss did not change significantly with the addition of a non-ionic surfactant, but it improved when more non-ionic surfactant were used. The tearing strength of enzyme-treated denim fabrics did not deteriorate. The stiffness of the treated fabrics improved with the enzymatic treatment with and without the non-ionic surfactant. The difference in color of fabrics treated with enzyme increased.