• Korean journal of applied entomology
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• v.46 no.2
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• pp.303-311
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• 2007

From the course of screening of useful xylanase producing microorganism from a phytophagous longicorn beetle, we isolated an extra-cellular xylanase producing strain, Paenibacillus sp. HY-8 from the intestine of Moechotypa diphysis adult. On the basis of morphological, biochemical and phylogenetic studies of the new isolate was identified as a Paenibacillus species. Production of xylanase in this strain was strongly induced by adding xylan to the growth medium and repressed by glucose or xylose. The highest xylanase production was attained in the M9 media containing 1% yeast extract and 0.5% birchwood xylan when cultured at $25^{\circ}C$ for 24 hrs. HY-8 producing xylanase showed superior hydrolytic activities against various plant source feedstuff than control xylanase produced by Tricoderma sp. at pH 6.0.

• Journal of Microbiology and Biotechnology
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• v.22 no.10
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• pp.1388-1394
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• 2012

A xylanase-producing thermophilic strain, Geobacillus sp. TC-W7, was isolated from a hot spring in Yongtai (Fuzhou, China). Subsequently, the xylanase gene that encoded 407 amino acids was cloned and expressed. The recombinant xylanase was purified by GST affinity chromatography and exhibited maximum activity at $75^{\circ}C$ and a pH of 8.2. The enzyme was active up to $95^{\circ}C$ and showed activity over a wide pH range of 5.2 to 10.2. Additionally, the recombinant xylanase showed high thermostability and pH stability. More than 85% of the enzyme's activity was retained after incubation at $70^{\circ}C$ for 90 min at a pH of 8.2. The activity of the recombinant xylanase was enhanced by treatment with 10 mM enzyme inhibitors (DDT, Tween-20, 2-Me, or TritonX-100) and was inhibited by EDTA or PMSF. Its functionality was stable in the presence of $Li^+$, $Na^+$, and $K^+$, but inhibited by $Hg^{2+}$, $Ni^{2+}$, $Co^{2+}$, $Cu^{2+}$, $Zn^{2+}$, $Pb^{2+}$, $Fe^{3+}$, and $Al^{3+}$. The functionality of the crude xylanase had similar properties to the recombinant xylanase except for when it was treated with $Al^{2+}$ or $Fe^{2+}$. The enzyme might be a promising candidate for various industrial applications such as the biofuel, food, and paper and pulp industries.

• Microbiology and Biotechnology Letters
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• v.48 no.2
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• pp.158-166
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• 2020

A gene coding for the xylanase was cloned from Paenibacillus woosongensis, followed by determination of its complete nucleotide sequence. This xylanase gene, designated as xyn10A, consists of 1,446 nucleotides encoding a polypeptide of 481 amino acid residues. Based on the deduced amino acid sequence, Xyn10A was identified to be a modular enzyme composed of a catalytic domain highly homologous to the glycosyl hydrolase family 10 xylanase and a putative carbohydrate-binding module (CBM) in the C-terminus. By using DEAE-sepharose and phenyl-sepharose column chromatography, Xyn10A was purified from the cellfree extract of recombinant Escherichia coli carrying a P. woosongensis xyn10A gene. The N-terminal amino acid sequence of the purified Xyn10A was identified to exactly match the sequence immediately following the signal peptide predicted by the Signal5.0 server. The purified Xyn10A was a truncated protein of 33 kDa, suggesting the deletion of CBM in the C-terminus by intracellular hydrolysis. The purified enzyme had an optimum pH and temperature of 6.0 and 55-60℃, respectively, with the kinetic parameters V_max and K_m of 298.8 U/mg and 2.47 mg/ml, respectively, for oat spelt xylan. The enzyme was more active on arabinoxylan than on oat spelt xylan and birchood xylan with low activity for p-nitrophenyl-β-xylopyranoside. Xylanase activity was significantly inhibited by 5 mM Cu²⁺, Mn²⁺, and SDS, and was noticeably enhanced by K⁺, Ni²⁺, and Ca²⁺. The enzyme could hydrolyze xylooligosaccharides larger than xylobiose. The predominant products resulting from xylooligosaccharide hydrolysis were xylobiose and xylose.

• Microbiology and Biotechnology Letters
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• v.43 no.3
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• pp.204-211
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• 2015

A bacterial strain capable of hydrolyzing xylan and locust bean gum (LBG) was isolated from the Saemangeum tideland of Korea. Based on the biochemical properties and the 16S rRNA gene sequence, the isolate YB-30 was identified as Bacillus subtilis. Xylanase productivity was increased effectively when B. subtilis YB-30 was grown in the presence of wheat bran, while mannanase productivity was increased drastically when grown in the presence of konjac or LBG. Particularly, maximum mannanase and xylanase activities were detected in the culture filtrate of media containing 3.5% konjac and 1% wheat bran. Both enzyme productivities reached maximum levels in the stationary growth phase. The culture filtrate exhibited the highest activity at 60℃ and pH 6.0 for mannanase and at 55℃ and pH 5.5 for xylanase, respectively. Both enzymes were not stable at high temperatures and xylanase was less stable than mannanase. In addition, wheat bran was hydrolyzed to liberate reducing sugar to a greater extent than rice bran by the culture filtrate because the wheat bran contained more arabinoxylan than the rice bran. Hence, xylanase and mannanase produced by B. subtilis YB-30 have a potential use as feed additive enzymes.

• Microbiology and Biotechnology Letters
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• v.20 no.5
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• pp.559-564
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• 1992

To increase the efficency of utilizing cellulosic biomass, a potent xylanase producing bacteria was isolated and identified as Bacillus sp. N-25. Extracellular xylanase from Bacillus sp. N-25 was partially purified by ammonium sulfate precipitation, DEAE-Sephadex A-25 and Sephadex G-IOO column chromatographies. The xylanase was single fraction on chromatography and was true xylanase without cellulase activity. The enzyme was stable at pH 6-8 and 80% activity was remained at $50^{\circ}C$ for 30 min, but was inhibited by $Hg^{2+}$, $Ag^{2+}$, and $Mn^{2+}$. From the fact that the major end product was xylose, we suggested that the enzyme is an exo-xylanase which may be a prime candidate for industrial use.

• Journal of Animal Science and Technology
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• v.51 no.5
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• pp.427-432
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• 2009

This study was undertaken to screen a high xylanase and mannanase producing microbes. In the first experiment, screening was undertaken against 50 samples of microorganisms having xylanase and mannanase activities from soil and fallen leaves. The screening process has focused on picking out fungi having high xylanase and mannanase activities under the solid-state fermentation. The xylanase and mannanase activities of 6 screened microbes were 0.9~1.6 unit/mL and 0.2~0.4 unit/mL, respectively, under the submerged fermentation condition. However, under the solid-state fermentation, xylanase and mannanase activities were 103.7~220.0 unit/g and 20.1~40.3 unit/g, respectively. Finally one microbe (E-3) was selected and its xylanase and mannanase activities were 197.3 unit/g and 39.9 unit/g, respectively. The morphological and molecular biological classification of E-3 showed 99% homology with the Aspergillus niger.

• The Korean Journal of Food And Nutrition
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• v.10 no.3
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• pp.344-349
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• 1997

A strain of Bacillus sp. DSNC 101, isolated from soil, produced up to 305.0 units/ml of xylanase when grown on te medium containing 2.0% xylan, 2.0% yeast extract and 0.4% K2HPO4. The strain produced xylanase in the presence of xylan, soluble starch, rice straw, Avicel, maltose, and lactose as a sole carbon source, but the enzyme was not synthesized in the presence of xylose, glucose or arabinose. The crude xylanase preparation did not show hydrolytic activity towards cellulosic substrates and PNPX, a chromogenic substrate for $\beta$-xylosidase. The temperature and pH optima for the xylanase production were 4$0^{\circ}C$ and 8.0, respectively. Xylanase synthesis was repressed by glucose, but not by xylose. The hydrolysis products of xylan catalyzed with the culture filtrate were xylooligosaccharides such as xylobiose and xylotriose but xylose was not detected by tin layer chromatography.

• Journal of Microbiology and Biotechnology
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• v.20 no.10
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• pp.1415-1423
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• 2010

An extracellular xylanase was purified to homogeneity by sequential chromatography of Fomitopsis pinicola culture supernatants on a DEAE-Sepharose column, a gel filtration column, and then on a MonoQ column with fast protein liquid chromatography. The relative molecular mass of the F. pinicola xylanase was determined to be 58 kDa by sodium dodecyl sulfate polyacrylamide gel electrophoresis and by size-exclusion chromatography, indicating that the enzyme is a monomer. The hydrolytic activity of the xylanase had a pH optimum of 4.5 and a temperature optimum of $70^{\circ}C$. The enzyme showed a $t_{1/2}$ value of 33 h at $70^{\circ}C$ and catalytic efficiency ($k_{cat}=77.4\;s^{-1}$, $k_{cat}/K_m$=22.7 mg/ml/s) for oatspelt xylan. Its internal amino acid sequences showed a significant homology with hydrolases from glycoside hydrolase (GH) family 10, indicating that the F. pinicola xylanase is a member of GH family 10.

• Journal of Microbiology and Biotechnology
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• v.17 no.11
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• pp.1811-1817
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• 2007

Extracellular enzymes from Lentinus edodes M290 on normal woods (Quercus mongolica) and waste logs from oak mushroom production were comparatively investigated. Endoglucanase, cellobiohydrolase, ${\beta}$-glucosidase, and xylanase activities were higher on waste mushroom logs than on normal woods after 1. edodes M290 inoculation. Xylanase activity was especially different, with a three times higher activity on waste mushroom logs. When the waste mushroom logs were used as a carbon source, a new 35 kDa protein appeared. After the purification, the optimal pH and temperature for xylanase activity were determined to be 4.0 and $50^{\circ}C$, respectively. More than 50% of the optimal xylanase activity was retained when the temperature was increased from 20 to $60^{\circ}C$, after a 240 min reaction. At $40^{\circ}C$, the xylanase maintained 93% of the optimal activity, after a 240 min reaction. The purified xylanase showed a very high homology to the xylanase family 10 from Aspergillus terreus by LC/MS-MS analysis. The highest Xcorr (1.737) was obtained from the peptide KWI SQGIPIDGIG SQTHLGSGGS WTVK originated from Aspergillus terreus, indicating that the 35 kDa protein was xylanase. This protein showed low homology to a previously reported L. edodes xylanase sequence.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.9
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• pp.1288-1295
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• 2009

The study was conducted to investigate the effects of different levels of xylanase on performance, blood parameters, intestinal morphology, microflora and digestive enzyme activities of broilers. The wheat-based diets were supplemented with 0, 500, 1,000, 5,000 U/kg xylanase. Xylanase supplementation significantly (p<0.05) improved the feed:gain ratio of broilers from 1 to 21 d and 1 to 42 d. Supplementing 500 U/kg and 1,000 U/kg xylanase improved (p<0.05) the villus height and the ratio of villus height to crypt depth in the small intestine. Excess supplementation of xylanase (5,000 U/kg) increased the villus height in the ileum (p<0.01) and the ratio of villus height to crypt depth in the duodenum and ileum (p<0.05). The microflora in the ileum and caecum, digestive enzyme activities in the small intestine and the concentrations of serum glucose, uric acid, insulin and IGF-I were not affected by the supplementation of xylanase. Excess level of xylanase (5,000 U/kg) had a tendency to induce the multiplication of E. coli and total aerobes. The results suggested that supplementing 500 U/kg and 1,000 U/kg xylanase was beneficial for broilers and excess xylanase supplementation resulted in no further improvement or negative effects.