• The Korean Journal of Mycology
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• v.17 no.2
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• pp.57-65
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• 1989

The effect of various cellulosic and hemicellulosic substrates on the induction of cellulase and xylanase complexes in Aapergillus nidulans was investigated. The most efficient substrates for the induction of cellulase and xylanase complexes were carboxymethylcellulose for endoglucanase, cellobiose for ${\beta}-glucosidase$, and xylan for endoxylanase and ${\beta}-xylosidase$, respectively. However, the mixtures of these substrates, especially CMC-xylan and CMC-xylan-laminarin mixture, were much more effective not only for the enhancement of the biosynthesis of all the cellulase and xylanase complexes but also for the balanced production of these enzyme components than individual substrate. The polyacrylamide gel electrophoresis followed by activity staining showed the variation in the patterns and relative intensity of ${\beta}-glucosidase$, endoglucanase and endoxylanase components in individual enzyme preparations from A. nidulans cultures grown on different substrates. These results suggest that the biosynthesis is of cellulase and xylanase systems in A. nidulans is regulated in coordination at the level of induction.

• Microbiology and Biotechnology Letters
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• v.23 no.3
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• pp.304-310
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• 1995

A thermophilic bacterium producing the extracellular cellulase-free xylanase was isolated from soil and has been identified as Bacillus sp. The optimal growth temperature was 50$\circ$C and the optimal pH, 7.0. Under the optimal growth condition, maximal xylanase production was 2.2 units/ml in the flask culture. The enzyme production was induced by xylan and xylose, but was repressed by sucrose or trehalose. The partially purified xylanase was most active at 70$\circ$C. It was found that the enzyme was stable at 65$\circ$C for 10 hours with over 75% of the activity. The enzyme was most active at pH 7.0 and retained 90% of its maximum activity between pH 5.0 and pH 9.0 though Bacillus sp. was not grown on alkaline conditions (>pH 8.0). In addition, the activity of xylanase was over 60% at pH 10.0. At the ambient temperature, the enzyme was stable over a pH range of 5.0 to 9.0 for 10 h, indicating that the enzyme is thermostable and alkalotolerant. The activity of xylanase was completely inhibited by metal ions including Hg$^{2+}$ and Fe$^{2+}$, while EDTA, phenylmethylsulfonyl fluoride (PMSF), $\beta$-mercaptoethanol and SDS didn't affect its activity. The enzyme was also identified to exert no activity on carboxymethylcellulose, laminarin, galactomannan, and soluble starch.

• Journal of Microbiology and Biotechnology
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• v.4 no.1
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• pp.49-55
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• 1994

A fungal strain capable of producing extracellular cellulase was isolated from farmland. It was identified as Aspergillus niger, and named Aspergillus niger KKS. Production of cellulase and xylanase by the A. niger KKS was studied through a shake-flask culture. The effects of culture conditions such as inoculum size, temperature, pH, and medium composition on the cellulase and xylanase production were examined. The optimum temperature and pH for the enzyme production were $30^{\circ}C$ and pH 7.0, respectively. The optimized medium was composed of 2.0% (w/v) rice straw, 0.5% (w/v) proteose peptone, 0.5% (w/v) $KH_2 PO_4$, 0.05% (w/v) yeast extract, 0.01% (w/v) $CoSO_4 \cdot 7H_2O$, and 0.05% (w/v) $CuSO$_4$\cdot 5H_2O$. When the strain was incubated with the optimized medium, it gave the activities of endoglucanase, $\beta$-glucosidase, $\beta$-xylosidase, xylanase were 3.80, 4.20, 4.00, 80.0 (IU/mL), respectively. Filter paper and cotton activities were 0.68 and 0.045 (IU/mL), respectively. The results of this study show that A. niger KKS is a potential organism with a wide spectrum of enzyme activities, such as those of $\beta$-glucosidase, $\beta$-xylosidase, and xylanase.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.35 no.1
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• pp.34-40
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• 2003

This study was carried out to select the useful bacteria which secret extracellula enzymes for enzymatic deinking agent of old newspaper. CMCase, FPase and xylanase activities of the bacteria liquid culture were measured at optimal growth conditions. Clear zone test was checked on the solid culture. The results of this study were as follow: Eight strains of 28 bacteria isolated from a paper mill soil ground were shown strong CMCase and xylanase activity with the clear zone test. The optimal pH and temperature for culture growth were 6~8 and 26~$34^{\circ}C$, respectively and optimal culture period were less than 60 hours. Based on CMCase, FPase and xylanase activity, strain No. 18, 21, 22 and 28 which were relatively higher than the other strains, were selected for further enzymatic deinking research.

• Journal of Microbiology and Biotechnology
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• v.12 no.1
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• pp.153-156
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• 2002

The characterization of a partially purified, cellulase-free, thermostable alkaline xylanase from thermoalkalophilic Bacillus sp. JB-99 was investigated. The xylanase production was the highest when birchwood xylan was added to a medium containing finely powdered rice bran, showing 4,826 IU$ml^-1$ of activity for 15 h of incubation. The partially purified xylanase exhibited an optimum temperature and pH at $70^C{\circ}$ and 10, respectively. The enzyme was stable at pH 5-11 at $50^C{\circ}$. The xylanase activity was strongly inhibited by $Hg^2+$, while dithiothreitol, cysteine, and ${\beta}$-mercaptoethanol enhanced the activity.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.36 no.3
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• pp.9-14
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• 2004

The useful fungi which secret extracellular enzymes was selected for deinking agent of old newsprint. Five fungal strains were isolated from a paper mill soil ground. The CMCase, FPase and xylanase activities of fungi on the liquid culture were investigated at optimal growth conditions. The results of this study were as follow: The optimal pH and temperature for culture growth were 4～8 and 27～$35^{\circ}C$, respectively. For screening of extracellular enzymes at optimal culture conditions the optimal culture period were less than 6-7 days. Fusarium pallidoroseum and Aspergiilus niger which shows relatively higher CMCase, FPase and xylanase activities than the other species were selected for further enzymatic deinking research.

• Journal of Mushroom
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• v.15 no.4
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• pp.249-253
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• 2017

Twelve strains of bacteria with cellulase and xylanase activities were isolated from spent mushroom substrates collected from button mushroom cultivation farm, Buye, Chungcheongnam-do in Korea. Among them, one strain, designated NO12, with higher cellulase and xylanase activities was selected by agar diffusion method. The strain NO12 was identified to be a Bacillus sp. by biochemical characteristics using Bacillus ID kit and MicroLog system. Comparative 16S rDNA gene sequence analysis showed that strain NO12 formed a distinct phylogenetic tree within the genus Bacillus and was most closely related to Bacillus subtilis with 16S rDNA gene sequence similarity of 99.2%. Based on its physiological properties, biochemical characteristics, and phylogenetic distinctiveness, strain NO12 was classified within the genus Bacillus, for which the name Bacillus subtilis NO12 was proposed. The cellulase and xylanase activities of B. subtilis NO12 were slightly increased according to bacterial population from exponential phase to stationary phase in the growth curve for B. subtilis NO12. The xylanase activity continuously increased from the beginning of the exponential phase and exhibited maximum activity in the middle of the exponential phase.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.37 no.4 s.112
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• pp.1-7
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• 2005

This study was carried out to investigate the characteristics of extracellular cellulase and xylanase from Fusarium pallidoroseum and Aspergillus niger, such as enzyme activity and stability by various pH, temperature and metal ions, for application into enzymatic deinking system. The optimal temperature and pH for enzyme activity and stability of Fusarium pallidoroseum and Aspergillus niger were $50^{\circ}C$, pH 5.0 and $60^{\circ}C$, pH 9.0, respectively. Certain metal ions, calcium and cobalt, brought to elevate cellulase and xylanase activity from F. pallidoroseum and A. niger. With these results we suggest that enzymatic deinking system should be proceed at $50\~60^{\circ}C$ under their optimal pH condition.

• The Korean Journal of Ecology
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• v.9 no.4
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• pp.231-241
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• 1986

The annual decomposition of cellulose and hemicellulose by microorganism and distribution of soil microbial flora were investigated in the humus horizon of a Pinus rigida stand in Mt. Kwanak. The cellulase activity was the lowest, 142$\mu$g glucose/g/hr from Dec. 1985 to Mar. 1986 and the highest, 760~1, 072$\mu$g glucose/g/hr in Jul. and Aug. 1985. The xylanase activity was 47% higher than the cellulase activity and was the lowest, 211~275$\mu$g xylose /g/hr from Feb. to Mar. 1986 and the highest as 799~1, 322$\mu$g xylose/g/hr from Jun. to Aug. 1986. The vertical distribution of the enzyme activity was decreased with the order of F, H, L, and A1 in both enzymes and the activities were exponentially decreased below L horizon, which suggests that most decomposition be done in F and H horizons with lots of organic matters. The SEM study slowed that the main decomposers of litters were fungi and initial attack into litters was also made by them. The enzyme activities of soil had strong correlations with the temperature and the precipitation. The correlation coefficients were 0.813 and 0.886 in the cellulase, and 0.673 and 0.626 in the xylanase for the temperature and the precipitation, respectively.

• Journal of Microbiology and Biotechnology
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• v.8 no.1
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• pp.49-52
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• 1998

A fungal strain able to produce filter paper activity (FPase) was isolated from soil by testing the ability to hydrolyze using filter paper. The isolated strain was identified as an Aspergilus sp. judging from its morphological and microscopical characteristics. The cellulase-xylanase system of Aspergillus sp. 8-17 was detected in situ after gel electrophoresis in the presence of SDS and showed that each protein pattern had a distinct polypeptide composition. ${\beta}$-1,4-Glucanase, cellobiohydrolase, and xylanase activity profiles differ from protein patterns. The Aspergillus sp. 8-17 hydrolytic enzymes responsible for the hydrolysis of ${\beta}$-glucan, MUC, and xylan have multiple active forms.