• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.36 no.1
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• pp.30-36
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• 2004

Waste papers(MOW and ONP) were deinked with alkaline cellulolytic enzyme from Coprinus cinereus 2249. The effectiveness of alkaline enzyme on sticky contaminant removal and bleaching of recycling pulp was investigated. The conclusions obtained from the results are as follows. The brightness of deinked pulps MOW and ONP was most high in 0.4IU enzyme treatment. \circled2 The removal effect of sticky contaminant was enhanced with alkaline cellulolytic enzyme treatment. Bleaching with sodium hydrosulfite was most effective in one and two stage bleaching after enzyme treatment of mixed wastepaper of MOW and colored paper. \circled4 The brightness of alkaline enzyme deinked ONP was increased 20％ with $H_2O$$_2$ bleaching.

• Journal of the Korean Wood Science and Technology
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• v.27 no.4
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• pp.65-71
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• 1999

This study was carried out to investigate the effect of xylanase pretreatment of the unbleached hardwood kraft pulp during the conventional Chlorine-Extraction- Hypochlorite (CEH) bleaching on pulp property. Optimum bleaching condition was evaluated by using Novozym produced from the fungus Humicola insolens. Also the effect of chelating agent prior to enzyme treatment was analyzed. The kappa number of enzymatic bleached pulp at the enzyme charge 10 IU/ml was slightly similar to that of bleached pulp without enzyme. By enzyme treatment, the chlorine charge in conventional CEH bleaching process of hardwood KP could be reduced by 17%, while no adverse effect on pulp yield and strength was. The optimum condition for enzyme pretreatment was 10 IU/ml xylanase charge, 3 to 4 hrs treatment, and 2% pulp consistency. In sugar composition in the enzyme pretreated pulp, arabinose and mannose were not much different, but more xylose was retained. This high content of hemicellulose in pulp seems to play an important role in pulp properties. The pulp pretreatment by chelating agent prior to enzyme treatment could improve the enzyme activity and enhance the bleaching effect at 0.2% diethylenetriamine pentaacetic acid (DTPA) charges.

• Textile Coloration and Finishing
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• v.10 no.6
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• pp.55-66
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• 1998

In order to investigate the detergency effects of various detergents to stained polyester & cotton fabric with solid soils such as carbon black, liquid paraffin and fat, the optimum washing conditions according to the types of washing agent, the assesment of detergency effect by the measurement of reflectance after and before washing were studied. The detergency effect of various detergents to stained polyester and cotton fabric increased by using the mixtures of bleaching and enzyme detergent. In order to obtain the excellent detergency effect, 2-step treatment, the pre-washing with bleaching agent and bleaching-enzyme mixture detergent treatment is preferred. In comparison of the detergency to polyester and cotton fabric, it is assumed that the detergency to polyester stained fabric was superior than that to cotton stained fabric because of the difference of adhesive force between soil material and fabric in preparing solid stained fabric.

• Journal of the Korean Graphic Arts Communication Society
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• v.26 no.1
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• pp.65-72
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• 2008

Kappa number and brightness were more increased with treatment of endo-xylanase than hydrogen-peroxide. In pulp bleaching process, endo-xylanse was most effective in the other enzyme treatment. Exo-xylanase was effective more than 4 unit treatment. Kappa number was tiny increased with enzyme ratio, but less than 4 unit treatment, increased with hydrogen peroxide treatment ratio. In more than 4 unit acetyl-estease treatment, Kappa number and brightness were not influenced with enzyme treatment ratio, but concentration of hydrogen-peroxide.

• Journal of Microbiology and Biotechnology
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• v.15 no.4
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• pp.689-693
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• 2005

Bacillus sp. JB-99, when grown in a chemically defined medium containing lactose as a carbon source, yielded 3,860 U/ml extracellular $\beta$-mannanase, which was high compared to other examined carbon sources. Among the nitrogen sources, yeast extract enhanced the enzyme activity. The enzyme production was growth-associated. The enzyme was optimally active at $65^{\circ}C$, pH 10, and had a half-life of 190 min at $65^{\circ}C$. N-Bromosuccinamide and $AgNO_3,\;CuSO_4$, and $HgCl_2$ strongly inhibited the enzyme, whereas $Ca^{2+}$ stimulated the enzyme activity. The $\alpha$-galactosidase enzyme production was not found in any of the enzyme assays.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.30 no.3
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• pp.15-21
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• 1998

Crude enzymes of Trichoderma viride and Phanerochaete chrysosporium were evaluated for their effect to brightness and physical properties of recycled pulp from newspaper and corrugated container board. The brightness of recycled pulp from newspaper increased with crude enzymes from Trichoderma viride and Phanerochaete chrysosporium. The brightness of recycled pulp of corrugated container board increased with crude enzyme from Phanerochaete chrysosporium, but decreased with crude enzyme from Trichoderma viride. The Δbrightness with chemical bleaching of crude enzyme treated pulp was lower than that of heat killed enzyme treated pulp, but the final brightness of pulp was increased. Modification of recycled paper with crude enzymes can result in a substantial increase in physical properties with little no loss in pulp freeness.

• Journal of Microbiology and Biotechnology
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• v.22 no.12
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• pp.1636-1643
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• 2012

Enzymatic pre-bleaching by modification of pulp fibers with xylanases is an attractive approach to reduce the consumption of toxic bleaching chemicals in the paper industry. In this study, an alkaliphilic endoxylanase gene was isolated from metagenomic DNA of a structurally stable thermophilic lignocellulose-degrading microbial consortium using amplification with conserved glycosyl hydrolase family 10 primers and subsequent genome walking. The full-length xylanase showed 78% sequence identity to an endo-${\beta}$-1,4-xylanase of Clostridium phytofermentans and was expressed in a mature form with an N-terminal His6 tag fusion in Escherichia coli. The recombinant xylanase Xyn3F was thermotolerant and alkaliphilic, working optimally at $65-70^{\circ}C$ with an optimal pH at 9-10 and retaining >80% activity at pH 9, $60^{\circ}C$ for 1 h. Xyn3F showed a $V_{max}$ of 2,327 IU/mg and $K_m$ of 3.5 mg/ml on birchwood xylan. Pre-bleaching of industrial eucalyptus pulp with no prior pH adjustment (pH 9) using Xyn3F at 50 IU/g dried pulp led to 4.5-5.1% increase in final pulp brightness and 90.4-102.4% increase in whiteness after a single-step hypochlorite bleaching over the untreated pulp, which allowed at least 20% decrease in hypochlorite consumption to achieve the same final bleaching indices. The alkaliphilic xylanase is promising for application in an environmentally friendly bleaching step of kraft and soda pulps with no requirement for pH adjustment, leading to improved economic feasibility of the process.

• Journal of the Korean Wood Science and Technology
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• v.25 no.2
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• pp.100-109
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• 1997

The objectives of this study was to decrease pollutions of bleaching effluent and was to enhanced brightness of non-chlorine bleached pulps by xylanase treatments. Xylanase cloned Esherichacoli(E. coli) capable of each of endo, exo-xylanase and acetyl-esterase were obtained from Bacillus stearothermophillus. These xylanase was maintained high activity in alkali and high temperature. Especially endo-xylanase would be more active in $60^{\circ}C$ and pH 11. Xylanase pretreatment(X) of unbleached pulp increased brightness, and decreased the degree of delignification. The degree of increase in brightness of pulp due to xylanase pretreatment was similar to non-enzyme treated pulp, regardless of the amount of enzyme added. Therefore, the addition of xylanase of 2 unit was recommended when considering costs of enzyme. The pulp bleached XO sequence had higher brightness and lower Kappa no, than O bleached pulp, while pulp bleached XP sequence had similar brightness and Kappa no. with P bleached pulp. In XOC/D, XOZ and XOP bleaching sequences, brightness and degree of delignification were improved. The C/D and Z stage bleached pulp was good effect on rate of raise in brightness and Kappa no., but P stage bleached pulp had similar level in non-enzyme treated bleaching sequence.

• Journal of the Korean Wood Science and Technology
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• v.27 no.4
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• pp.72-79
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• 1999

The ability of several wood rotting fungi for decolorization of two anthracene derivatives, Carminic acid (CA) and Remazol brilliant blue R (RBBR), and hardwood KP bleaching liquor (BL) as well as laccase activities in these fungi were studied. The enzyme activity appeared exclusively in fungi destaining RBBR and CA, but in the case of BL, such relationship was not observed. The laccase enzyme was released into the decolorization media and its inducible (but not constitutive) forms shown destaining activity. The purified inducible forms of Kuehneromyces mutabilis and Pleurotus ostreatus laccase destained CA. Thus the possible differentiation between specificity of particular LAC forms was confirmed. In addition the nitrogen starvation induced both laccase and CA destaining activities, but the increase was higher for decolorization of CA than LAC activity. Probably LAC would be only partly responsible for decolorization of this dye. This results suggested that purified LACs decolorize CA, however its destaining activities were considerably lower than the activities on syringaldazine.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.30 no.1
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• pp.44-58
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• 1998

This study was carried out to bleach the Oakwood kraft pulp without the elemental chlorine using the xylanase or wastewater(We : wastewater enzymes) effluented from the submerged biofilter reactor containing the fungi, Phanerorhaete sordida YK-624. So in this research, the proper treatment conditions (pH, temperature, dosage and time) were investigated respectively. And after the various kinds of multistage bleaching of pulps, the properties of pulps were tested. From the experimental results, we can conclude as follows. In the treatments of Oakwood kraft pulps with xylanase, the proper pH, temperature, enzyme dosage and time were 8.0, $35^{\circ}C$ , 400 EXU/kg and 1 hr. respectively. And in the case of treatment with a wastewater(We) effluented from the submerged biofilter reactor, the proper pH, temperature and time were 5.5, $37^{\circ}C$ and 2 hr. respectively. On the other hand, Oakwood kraft pulps were bleached by the method of a multistage bleaching using xylanase or We instead of elemental chlorine Consequently the strengthes and brightnesses of pulps bleached by the method mentioned above were lower than those of pulp bleached by the conventional method using the elemental chlorine. But it is possible to improve the brightnesses through the increase of chlorine dioxide dosage or use of hydrogen peroxide in the final bleaching stage.