• Journal of Microbiology and Biotechnology
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• v.19 no.8
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• pp.823-828
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• 2009

An endo-${\beta}-1$,4-xylanase (${\beta}$-xylanase) from Trichoderma harzianum C4 was purified without cellulase activity by sequential chromatographies. The specific activity of the purified enzyme preparation was 430 units/mg protein on D-xylan. The complementary DNA (cDNA) encoding ${\beta}$-xylanase (xynII) was amplified by PCR and isolated from cDNA PCR libraries constructed from T. harzianum C4. The nucleotide sequence of the cDNA fragment contained an open reading frame of 663 bp that encodes 221 amino acids, of which the mature protein is homologous to several ${\beta}$-xylanases II. An intron of 63 bp was identified in the genomic DNA sequence of xynII. This gene was expressed in Saccharomyces cerevisiae strains under the control of adh1 (alcohol dehydrogenase I) and pgk1 (phosphoglycerate kinase I) promoters in 2 ${\mu}$-based plasmids, which could render recombinants able to secrete ${\beta}$-xylanase into the media.

• Journal of Microbiology and Biotechnology
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• v.16 no.8
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• pp.1255-1261
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• 2006

An alkaliphilic bacterium, Bacillus sp. strain BK, was found to produce extracellular cellulase-free xylanolytic enzymes with xylan-binding activity. Since the pellet-bound xylanase is eluted with 2% TEA from the pellet of the culture, they contain a xylan-binding region that is stronger than the xylan-binding xylanase of the extracellular enzyme. The xylanases had a different molecular weight and xylan-binding ability. The enzyme activity of xylanase in the extracellular fraction was 6 times higher than in the pellet-bound enzyme. Among the enzymes, xylanase had the highest enzyme activity. When Bacillus sp. strain BK was grown in pH 10.5 alkaline medium containing xylan as the sole carbon source, the bacterium produced xylanase, arabinofuranosidase, acetyl esterase, and $\beta$-xylosidase with specific activities of 1.23, 0.11, 0.06, and 0.04 unit per mg of protein, respectively. However, there was no cellulase activity detected in the crude enzyme preparation. The hydrolysis of agricultural residues and kraft pulps by the xylanolytic enzymes was examined at 50$^{\circ}C$ and pH 7.0. The rate of xylan hydrolysis in com hull was higher than those of sugarcane bagasse, rice straw, com cop, rice husk, and rice bran. In contrast, the rate of xylan hydrolysis in sugarcane pulp was 2.01 and 3.52 times higher than those of eucalyptus and pine pulp, respectively. In conclusion, this enzyme can be used to hydrolyze xylan in agricultural residues and kraft pulps to breach and regenerate paper from recycled environmental resources.

• Journal of Microbiology and Biotechnology
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• v.23 no.6
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• pp.794-801
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• 2013

This paper reports the production and characterization of crude xylanase from the newly isolated Humicola sp. Ly01. The highest (41.8 U/ml) production of the crude xylanase was obtained under the optimized conditions (w/v): 0.5% wheat bran, 0.2% $KH_2PO_4$, and 0.5% peptone; initial pH 7.0; incubation time 72 h; $30^{\circ}C$; and 150 rpm. A considerable amount of the crude xylanase was induced using hulless barley bran or soybean meal as the carbon source, but a small amount of the enzyme was produced when supplementary urea was used as the nitrogen source to wheat bran. The crude xylanase showed apparent optimal cellulase-free xylanase activity at $60^{\circ}C$ and pH 6.0, more than 71.8% of the maximum xylanase activity in 3.0-30.0% (v/v) ethanol and more than 82.3% of the initial xylanase activity after incubation in 3.0-30.0% (v/v) ethanol at $30^{\circ}C$ for 2 h. The crude xylanase was moderately resistant to both acid and neutral protease digestion, and released 7.9 and 10.9 ${\mu}mol/ml$ reducing sugar from xylan in the simulated gastric and intestinal fluids, respectively. The xylooligosaccharides were the main products of the hydrolysis of xylan by the crude xylanase. These properties suggested the potential of the crude enzyme for being applied in the animal feed industry, xylooligosaccharides production, and high-alcohol conditions such as ethanol production and brewing.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.37 no.1 s.109
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• pp.38-46
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• 2005

This study was focused on the optimum culture condition in CMCase, FPase and xylanase activities of two fungal strains that secret extracellular enzymes for using enzymatic deinking agent to old newsprint. The results of this study were as follows. When Fusarium pallidoroseum was grown on the medium, containing of rice bran+xylan $2.0\%,\;peptone\;0.6\%,\;KH_2PO_4\;0.075\%\;and\;MnSO_4\;0.06\%\;with\;pH\;9.0,\;at\;29^{\circ}C$ for 6 days, the quantitative degree of extracellular enzyme production was the highest. Optimum culture condition for Aspergillus niger was pH 5.0, $27^{\circ}C$ incubating temperature and 7 days incubation period on liquid medium, containing of CMC+xylan $2.5\%,\;yeast\;extract\;0.4\%,\;K_3PO_4\;0.05\%\;and\;CaCl_2+FeSO_4\;0.08\%$. Aspergillus niger was fairly higher FPase and xylanase activities than Trichoderma reesei ATCC 28217.

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.449-452
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• 2002

A filamentous microorganism was isolated from completely rotten wood for the production of cellulolytic enzyme. The Trichoderma sp. FJ1 produced a large amount of cellulolytic enzymes, such as CMC, xylanase, ${\beta}-glucosidase$, and avicelase. For the production of the enzymes, when cellulolsic wastes were used as carbon sources of strain FJ1, rice straw showed higher enzyme activities than sawdust and pulp. The activities of CMC, xylanase, ${\beta}-glucosidase$, and avicelase were 2.95, 5.89, 0.45, and 0.12 U/ml in use of rice straw, respectively. To enhance production of the enzymes, the mixture substrate of rice straw and commercial cellulosic materials was investigated as carbon sources. The highest activities of CMCase, ${\beta}-glucosidase$, and avicelase were found in the mixture of rice straw and avicel, particularly rice straw:avicel (50:50), and the highest xylanase was obtained in the mixture ratio of 71:29. Bacto peptone addition of 0.1% showed enhanced production of the cellulolytic enzymes in which the activities of CMCase, xylanase ${\beta}-glucosidase$, and avicelase were 19.23, 27.18, 1.28, and 0.53 U/ml, respectively. The production of the enzymes using rice straw was efficiently induced in present of avicel and pulp containing high content of cellulose. Consequently, the filamentous microorganism, strain FJ1 utilized various cellulosic wastes as carbon sources and cellulases productivities were excellent compared to those of others strains reported previously, suggesting that the strain FJ1 will be expected as a favorable candidate for biological saccharification of cellulosic wastes in further.

• Applied Biological Chemistry
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• v.19 no.3
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• pp.139-144
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• 1976

In order to investigate the properties of enzymes from two strains of mold, reported in the previous paper, (1) studies have been made concerning the characteristics of cellulase of Aspergillus niger-SM6 and Trichoderma viride-SM10, and summarized as follows. 1. In the semi-purification the recovery of ${\beta}-glucosidase$ was the highest when 80-90% ethanol was used and 0.8 saturation of $(NH_4)_2SO_4$. 2. The characteristics of the semi-purified enzyme were as follows. Aspergillus niger-SM6 Trichoderma viride-SM10 Optimum pH 3.5 4.0 pH stability 3.0-6.0 3.0-6.0 Optimum temperature $60^{\circ}C$ $60^{\circ}C$ Heat stability below $60^{\circ}C$ below $50^{\circ}C$ Optimum reaction time 30 min. 60 min. Optimum CMC concentration 3% 3% 3. The Km values of CMCase were 0.8% and 1.01 for Aspergillus niger-SM6 and Trichoderma viride-SM10, respectively. 4. In the strain of Aspergillus niger-SM6, there were high activity of xylanase and pectinase.

• Journal of Microbiology and Biotechnology
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• v.2 no.1
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• pp.7-13
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• 1992

A moderately thermophilic, alkalophlic and powerful crystalline cellulose-digesting bacterium, Bacillus K-12, was isolated from filter paper wastes and found to be similar to Bacillus circulans or Bacillus pumilis, except for its ability to grow at a moderately high pH and temperature. The isolate grew at a pH ranging from 6 to 10 and at a temperature ranging from 35 to $65^{\circ}C$ and produced a large amount of cellulase components containing avicelase, xylanase, CMCase, and FPase when grown in avicel medium for 5 to 7 days at $50^{\circ}C$. The crude enzyme preparation from the culture broth hydrolyzed xylan, raw starch, pullulan and ${\beta}-1,3$ glucan such as laminarin. Furthermore, the enzyme hydrolyzed crystalline cellulose to cellobiose and glucose and had a broad pH activity curve (pH 6~9). The enzyme was stable up to $70^{\circ}C$.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.29 no.2
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• pp.16-24
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• 1997

This experiment was mainly performed with a biological treatment of laser printed paper using enzyme, We got the following conclusions : In the case of nonionic surfactant treatment, brightness, residual ink contents and several strength properties of deinked paper were excellent at the low dosage of cellulase 0.05%. When mixed cellulase and xylanase was used, yield was increased as the dosage increased up to 0.2%, but brightness was decreased at the same condition. In contrast, deinking efficiency of anionic type was reduced in terms of brightness, residual ink contents, and tensile strength. As flotation time was increased, yield decreased and brightness increased slightly. On the other hand, the addition of surfactant during repulping process showed better result than that during flotation process.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 1999.04b
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• pp.291-295
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• 1999

Coprinus cinereus 2249 that is a kind of basidiomycetes constitutively produced alkaline carboxymethyl cellulase (CMCase), filter paper cellulase (FPase) and xylanase. Crude enzymes prepared with optimal conditions showed higher FPase activity than CMCase activity. The FPase was most active at pH 9 at 50$^{\circ}C$. When applied on deinking of the old newsprint (ONP), it increases the freeness and brightness due to effect of hydrolysis at 0.1% enzyme concentration. Also, The physical properties of deinked pulp were improved.

• Mycobiology
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• v.39 no.2
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• pp.118-120
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• 2011

The ability of Ganoderma to produce extracellular enzymes, including ${\beta}$-glucosidase, cellulase, avicelase, pectinase, xylanase, protease, amylase, and ligninase was tested in chromogenic media. ${\beta}$-glucosidase showed the highest activity, among the eight tested enzymes. In particular, Ganoderma neo-japonicum showed significantly stronger activity for ${\beta}$-glucosidase than that of the other enzymes. Two Ganoderma lucidum isolates showed moderate activity for avicelase; however, Ganoderma neojaponicum showed the strongest activity. Moderate ligninase activity was only observed in Ganoderma neo-japonicum. In contrast, pectinase, amylase, protease, and cellulase were not present in Ganoderma. The results show that the degree of activity of the tested enzymes varied depending on the Ganoderma species tested.