• Microbiology and Biotechnology Letters
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• v.17 no.3
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• pp.178-182
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• 1989

A gene coding for a xylanase of thermophilic alkalophilic Bacillus sp. K-17 was cloned in Escherichia coli C600 with pBR322. Plasmid pAXl13 was isolated from a transformant producing xylanase, and the xylanase gene was located in a 4.3 Kb HindIII fragment. Biotinylated pAXl13 hybridized to a 4.3 Kb HindIII fragment from chromosomal DNA of thermophilic alkalophilic Bacillus sp. K-17. The xylanase activity was observed in the extracellular curture fluid of E. coli carrying pAXl13. The pAXl13-encoded xylanase had the same enzymatic properties as those of xylanase I produced by thermophilic alkalophilic Bacillus sp. K-17.

• Microbiology and Biotechnology Letters
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• v.17 no.2
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• pp.85-87
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• 1989

Cultural conditions for the formation of extracellular xylanase by Candida sp. X-6-41 were investigated. The xylanase was not produced in culture medium containing polypeptone or yeast extract as a nitrogen source, respectively, whereas the enzyme w8s produced in chemically defined medium containing (NH$_4$)$_2$SO$_4$as a sole nitrogen source. The xylanase production was affected by the amino acids such as isoleucine and tryptophan. The enzyme production of the strain was completely inhibited by the addition of isoleucine in the culture medium, but enhanced by tryptophan below the concentration of 25$\mu$g/$m\ell$.

• Microbiology and Biotechnology Letters
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• v.30 no.2
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• pp.123-128
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• 2002

A bacterium producing the extracellular xylanase was isolated from soil and has been identified as a Bacillus sp. strain. The isolate, named Bacillus sp. AMX-4, was shown to be similar to B. subtilis strain on the basis of its chemical compositions. The xylanase of culture supernatant was most active at 50℃ and pH 6.0. The additional carbon sources including monosaccharides, disaccharides, wheat bran, and rice straw increased the enzyme productivity. Especially, the maximum xylanase productivity was reached 29.2 units/ml in LB medium supplemented with 1.5％ (w/v) xylose, which was 16-folds more than that in LB medium. As the results of investigating the effects of xylose on cell growth and xylanase productivity of Bacillus sp. AMX-4, increase of xylanase production was owing to the induction of xylanase biosynthesis. It was also found that the enzyme production was in association with the growth of Bacillus sp. AMX-4.

• 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 the Korean Graphic Arts Communication Society
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• v.26 no.1
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• pp.17-28
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• 2008

The wood-pulp is treated with the three enzymes; Endo-xylanase, exo-xylanase and acetyl-esterase. The maximum value of relative activity appeared 0.95 in acetyl-esterase at $40^{\circ}C$, 0.9 in exo-xylanase at $40^{\circ}C$, and 0.8 in endo-xylanase at $50^{\circ}C$, respectively. And it has measured 0.8 in endo-xylanase, 0.95 in acetyl-esterase at pH 6 and 0.9 in exo-xylanase at pH 5, while the maximum value of relative activity does not rely on reaction time for three enzymes treatment, and the value was about 0.9, respectively. We have watched that decreased Kappa number and increased brightness. And it turned out that the three enzyme produced a lot of reducing sugar with wood-pulp treatment.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.1
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• pp.66-74
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• 2005

Three experiments were conducted to study the property of xylanase and the effects of xylanase in wheat-based diets on growth performance of broilers, respectively. Experiment 1 was performed in vitro to evaluate the effect of different pH and temperature on xylanase activity, and to evaluate the enzymic stability under different conditions. The results indicated that the optimum temperature and pH for xylanase activity were $50^{\circ}C$ and 4.5, respectively. The activity of enzyme solution was reduced rapidly after the treatment of water bath above $60^{\circ}C$ for 10 min. The enzyme was relatively stable at pH 3.5 to 8.0 and deteriorated when incubated at pH below 3.5. In Experiment 2, a total of 378 d-old male Arbor Acres broilers were randomly distributed to 7 different treatments with 6 replicates (9 birds) in each treatment. The treatments were as follows: (1) corn based diet (CS), (2) wheat based diet (WS), (3) WS+ 0.05% xylanase, (4) WS+0.15% xylanase, (5) WS+0.25% xylanase, (6) WS+0.35% xylanase, (7) WS+0.45% xylanase. The results showed that the body weight and feed/gain ratio of the broilers fed wheat-based diets have been significantly improved (p<0.05) compared to that fed corn-based diet in the first 3 wk. With regard to the wheat-based diets, the xylanase supplementation had a tendency to improve the growth performance in first 3 wk. After 3 wk, no significant difference (p>0.05) was found among all these different treatments. The supplementation of xylanase and the type of diets did not affect the feed intake but increased the concentration of triglyceride in serum. In Experiment 3, a total of 360 d-old male Arbor Acres broilers were assigned to 30 groups with 12 birds in each group randomly. These groups were then randomly distributed to 5 different treatments with 6 replicates within each treatment. The broilers of each treatment were fed one of the diets as follows: (1) Corn based diet, (2) White wheat based diet (WW) (3) White wheat based diet+0.25% xylanase, (4) Red wheat based diet, (5) Red wheat based diet+0.25% xylanase. The results showed that the body weight and feed/gain ratio had been significantly improved (p<0.05) by xylanase supplementation in the first 2 or 3 wk. The effect of xylanase in red wheat diet is a little higher than that used in white wheat diet. From the results of the present experiments, it can be concluded that the supplementation of Aspergillar xylanase can improve the performance of the broilers fed the wheat-based diet.

• Journal of Microbiology and Biotechnology
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• v.25 no.12
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• pp.2016-2023
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• 2015

Xylanase plays important roles in a broad range of industrial production as a biocatalyst, and its applications commonly require immobilization on supports to enhance its stability. Aluminum hydroxide, a carrier material with high surface area, has the advantages of simple and low-cost preparation and resistance to biodegradation, and can be potentially used as a proper support for xylanase immobilization. In this work, xylanase from Thermomyces lanuginosus was immobilized on two types of aluminum hydroxide particles (gibbsite and amorphous Al(OH)₃) through adsorption, and the properties of the adsorbed enzymes were studied. Both particles had considerable adsorptive capacity and affinity for xylanase. Xylanase retained 75% and 64% of the original catalytic activities after adsorption to gibbsite and amorphous Al(OH)₃. Both the adsorptions improved pH and thermal stability, lowered activation energy, and extended lifespan of the immobilized enzyme, as compared with the free enzyme. Xylanase adsorbed on gibbsite and amorphous Al(OH)₃ retained 71% and 64% of its initial activity, respectively, after being recycled five times. These results indicated that aluminum hydroxides served as good supports for xylanase immobilization. Therefore, the adsorption of xylanase on aluminum hydroxide particles has promising potential for practical production.

• Korean journal of food and cookery science
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• v.31 no.1
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• pp.18-25
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• 2015

This study investigated the baking properties of sorghum with the addition of xylanase or Pentopan, which is a baking additive containing xylanase. The control bread was made with a 30% substitution for wheat flour and the optimum level of enzyme addition was 0.75 mg/g flour for Pentopan and 5 mg/g flour for xylanase. The water binding capacity of wheat flour increased with the addition of sorghum, but decreased with the addition of either xylanase or Pentopan. The resistance of dough increased while extensibility decreased with the addition of sorghum; however, resistance decreased while extensibility increased with the addition of the enzyme. Specific volume of bread decreased significantly with the addition of sorghum. However, the specific volume was significantly recovered with the addition of enzyme. Crumb firmness was higher in the sorghum-added sample, but crumb firmness of the bread decreased with the addition of the enzyme. The crumb firmness of bread with added xylanase decreased significantly in 24 hours. These results demonstrated that adding sorghum with either xylanase or Pentopan that included xylanase increased specific volume and decreased crumb firmness whereas sorghum decreased the quality of fermented bread when added to wheat flour. The firmness rate of fermented bread particularly decreased with the addition of pure xylanase.

• 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.32 no.1
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• pp.22-28
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• 2004

A new moderate thermophilic bacterial strain DG-22 which produces thermostable xylanase was isolated from a timber yard soil in Kyungju, Korea. On the basis of morphological, biochemical and phylogenetic studies 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. No cellulase activity was detected. The temperature and pH for optimum activity were 8$0^{\circ}C$ and 5.0-5.5, respectively. The crude xylanase was stable at $60^{\circ}C$ and retained 60% of initial activity after 2h at $70^{\circ}C$. Zymogram analysis of the culture supernatant showed two xylanase active bands with molecular masses of 22 and 30 kDa.