• 한국어병학회지
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• 제6권1호
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• pp.1-10
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• 1993

발병한 양식 메기로 부터 vibrio속 균주를 분리하였다. 분리된 균주는 생물학적 생화학적 특성에 기초하여 동정한 결과 V. ordalii로 동정 되었다. 분리균은 glucose, lactose, maltose 와 salicine으로 부터 산을 생산 하였으며, arabinose, galactose, inocitol과 xylose는 이용하지 못하였다. 분리된 V. ordalii를 각각 KL-1, KL-2라 명명하였다. KL-l과 KL-2는 생리학적 특성이 유사하였다. 즉, pH 5-10, NaCl 0%~6.0%에서 발육하였으며, 또한 NaCl 7.0%, pH 10이상 그리고 pH5이하에서는 발육하지 않았다. KL-1 균주를 건강한 메기에 인공 감염시킨 결과 양식장에서 발병된 증상과 동일한 출혈성 궤양이 유발되었다. 감염 24시간 후에 나타난 흙은 반점은 접종 부위 주변에서 부터 확장되기 시작했으며, 감염 120시간 후부터는 배지느러미 부위까지 궤양이 확장되었다. 각각 온도에 따른 실험에서는 $25^{\circ}C$에서 폐사율이 70%로 나타났다. 약제 감수성 시험에서 KL-1 과 KL-2 균주는 모두 GM, K, N, S와 SxT에 감수성을 나타내었으나, CF 및 $L_2$와 VA에는 저항성을 나타내었다.

• Journal of Microbiology and Biotechnology
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• 제31권2호
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• pp.272-279
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• 2021

Two genes encoding probable α-ʟ-arabinofuranosidase (E.C. 3.2.1.55) isozymes (ABFs) with 92.3% amino acid sequence identity, ABF51A and ABF51B, were found from chromosomes 3 and 5 of Saccharomycopsis fibuligera KJJ81, an amylolytic yeast isolated from Korean wheat-based nuruk, respectively. Each open reading frame consists of 1,551 nucleotides and encodes a protein of 517 amino acids with the molecular mass of approximately 59 kDa. These isozymes share approximately 49% amino acid sequence identity with eukaryotic ABFs from filamentous fungi. The corresponding genes were cloned, functionally expressed, and purified from Escherichia coli. SfABF51A and SfABF51B showed the highest activities on p-nitrophenyl arabinofuranoside at 40~45℃ and pH 7.0 in sodium phosphate buffer and at 50℃ and pH 6.0 in sodium acetate buffer, respectively. These exoacting enzymes belonging to the glycoside hydrolase (GH) family 51 could hydrolyze arabinoxylo-oligosaccharides (AXOS) and arabino-oligosaccharides (AOS) to produce only ʟ-arabinose, whereas they could hardly degrade any polymeric substrates including arabinans and arabinoxylans. The detailed product analyses revealed that both SfABF51 isozymes can catalyze the versatile hydrolysis of α-(1,2)- and α-(1,3)-ʟ-arabinofuranosidic linkages of AXOS, and α-(1,2)-, α-(1,3)-, and α-(1,5)-linkages of linear and branched AOS. On the contrary, they have much lower activity against the α-(1,2)- and α-(1,3)-double-substituted substrates than the single-substituted ones. These hydrolases could potentially play important roles in the degradation and utilization of hemicellulosic biomass by S. fibuligera.

• Mycobiology
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• 제37권4호
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• pp.286-294
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• 2009

Heteropolysaccharides isolated from liquid cultures of nine Tremella species contained 0.3 to 1.2% protein, 2.7 to 5% ash, 0.9 to 3.4% acetyl groups, 76.5 to 84.2% carbohydrates and trace amounts of starch. The polysaccharides in aqueous solution were slightly acidic (pH 5.1 to 5.6). They consisted of the following monomeric sugars: fucose, ribose, xylose, arabinose, mannose, galactose, glucose and glucuronic acid. The backbones of the polysaccharide structures consisted of $\alpha$-(1$\rightarrow$3)-links while the side chains were $\beta$-linked.

• Asian-Australasian Journal of Animal Sciences
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• 제27권6호
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• pp.855-861
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• 2014

This experiment was performed to investigate the effects of exogenous xylanase supplementation on performance, nutrient digestibility and the degradation of non-starch polysaccharides (NSP) in different sections of the gastrointestinal tract (GIT) of broilers fed wheat-based diets. A total of 120 7-day-old Arbor Acres broiler chicks were randomly allotted to two wheat-based experimental diets supplemented with 0 or 1.0 g/kg xylanase. Each treatment was composed of 6 replicates with 10 birds each. Diets were given to the birds from 7 to 21 days of age. The results showed that xylanase supplementation did not affect feed intake, but increased body weight gain of broiler at 21 day of age by 5.8% (p<0.05) and improved feed-to-gain ratio by 5.0% (p<0.05). Xylanase significantly increased (p<0.05) ileal digestibilities of crude protein (CP) by 3.5%, starch by 9.3%, soluble NSP by 43.9% and insoluble NSP by 42.2% relative to the control group, respectively. Also, compared with the control treatment, xylanase addition increased (p<0.05) total tract digestibilities of dry matter by 5.7%, CP by 4.1%, starch by 6.3%, soluble NSP by 50.8%, and had a tendency to increase (p = 0.093) insoluble NSP by 19.9%, respectively. The addition of xylanase increased the concentrations of arabinose and xylose in the digesta of gizzard, duodenum, jejunum, and ileum (p<0.05), and the order of their concentration was ileum>jejunum>duodenum>>gizzard> caecum. The supplementation of xylanse increased ileal isomaltriose concentration (p<0.05), but did not affect the concentrations of isomaltose, panose and 1-kestose in the digesta of all GIT sections. These results suggest that supplementation of xylanase to wheat-based diets cuts the arabinoxylan backbone into small fragments (mainly arabinose and xylose) in the ileum, jejunum and duodenum, and enhances digestibilites of nutrients by decreasing digesta viscosity. The release of arabinose and xylose in the small intestine may also be the important contributors to the growth-promoting effect of xylanase in broilers fed wheat-based diets.

• 한국식품조리과학회지
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• 제19권5호
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• pp.616-623
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• 2003

Bran(1∼5번)의 총 평균 $\beta$-glucan 함량은 5.52%로서 가장 높은 회수율 (48.5%)을 보인 추출 조건은 pH 10 및 45$^{\circ}C$, 다음은 pH 7 및 45$^{\circ}C$로 나타났다. 보리겨의 gum 물질은 배유 부분의 gum 물질과는 달리 상당량의 전분, 단백질이 혼입되어 있었고 정제된 $\beta$-glucan 도 단백질 및 전분 함량이 감소되긴 하였으나 호분층 안쪽의 bran 1,2,3,4에서도 $\beta$-glucan 함량이 78.2∼85.8%를 나타내어 세포벽의 peptide, arabinoxylan 등과 강하게 결합됨을 알 수 있었다. $\beta$-glucan을 이루는 구성당은 glucose가 주종이며, 그 외 arabinose, xylose, mannose, galactose였으며, 분자량은 보리겨에 따라 차이가 있으나 bran 1∼3의 경우 4.09 x $10^{5}$ 에서 4.41 x $10^{5}$ 정도의 분자량이 90% 이상을 차지하였으며, 다당 고유의 특성인 분자량의 분산성을 나타내었다. 한편 $\beta$-glucan의 구조 역시 보리겨에 따라 다소 차이가 있으나 $\beta$-(1\$\longrightarrow$3) 결합, $\beta$-(1\$\longrightarrow$4) 결합이 대부분을 차지하였고, $\beta$-glucan용액의 유동특성은 농도가 증가함에 따라 유동지수는 감소하여 의가소성이 증가하는 경향을 나타내었다.

• 한국미생물·생명공학회지
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• 제16권2호
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• pp.119-125
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• 1988

Cellulomonas sp. CS1-1 생성의 $\beta$-glucosidase는 cell-bound 효소이었으며, Avicelase와 Carboxymethyl-cellulase (CMCase)는 extracellular 효소로 존재함을 확인하였다. Cellobiose나 CMC 최소배지에서의 균의 생장은 cellobiose보다 glucose 첨가시에 현저히 증가하였다. Cellobiose나 CMC 최소배지에서의 $\beta$-glucosidase 생합성은 glucose 첨가로 현저히 억제되었으나, CMC 최소배지에 cellobiose를 첨가하였을 경우, glucose에 의한 억제 효과와는 반대로, 효소의 생성은 오히려 촉진되었다. 그 외의 탄소원에 관한 영향을 조사한 결과 CMC, 전분, maltose 등의 첨가도 glycerol, arabinose, xylose, trehalose의 첨가시 보다 효소의 생성이 증가되었다. 이상의 결과로 $\beta$-glucosidase 생합성은 glucose에 의하여 catabolite repression을 받았으며, cellobiose, CMC, starch등은 다른 당류보다 효소생성을 현저히 유도하였으므로, 이 효소는 inducible enzyme임을 알 수 있었다. 효소생성에 미치는 질소원을 조사한 결과는 yeast extract가 peptone이나 ammonium sulfate보다 효소생성을 증가시켰다. 효소의 특성을 조사한 결과, 50mM MgCl$_2$가 포함된 10mM potassium phosphate buffer (pH 7.0)에서 효소의 역가가 증가하였고, 최적 pH는 6.0이었고 최적온도는 42$^{\circ}C$ 이었다. p-nitrophenyl-$\beta$-D-glucoside의 농도에 대한 glucose의 Km값은 0.265mM 이었고 $\beta$-D(+)-glucose에 대한 Ki값은 9.0 mM 이었다.

• Asian-Australasian Journal of Animal Sciences
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• 제13권3호
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• pp.376-380
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• 2000

This study was conducted to investigate protein and carbohydrate utilization of Micrococcus varians, Staphylococcus carnosus and Staphylococcus xylosus. Sensitivity to pH, sodium chloride, potassium sorbate and sodium nitrite of these strains was also determined. In Chinese-style beaker sausage manufacturing, the growth rate of these strains during the curing period ($20^{\circ}C$ and $30^{\circ}C$) was evaluated. The results indicated that no strains could hydrolyze azo-casein and sarcoplasmic protein and only S. xylosus could hydrolyze gelatin at $30^{\circ}C$. All of these strains could oxidize and ferment fructose and mannitol. S. carnosus and S. xylosus could slightly oxidize lactose and utilize citrate. Arabinose was oxidized by S. xylosus and sorbitol was oxidized by S. carnosus. Growth of M. varians was restricted at pH 5.0 and S. carnosus and S. xylosus were restricted at pH 4.5. S. xylosus and S. carnosus were able to grow with 0.1~0.5% potassium sorbate, 50~200 ppm sodium nitrite or 1~15% sodium chloride. S. xylosus had a higher growth rate than the other strains. Staphylococcus species grew well during curing period of Chinese-style beaker sausage then followed by Micrococcaceae.

• 한국식품영양학회지
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• 제10권3호
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• pp.344-349
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• 1997

Bacillus sp. DSNC 101은 탄소원으로 2.0% oat spelts xylan, 질소원으로 2.0% yeast extract, 그리고 인산염으로 0.4% K2HPO4를 함유한 pH 8.0의 xylanase 생산 배지에서 4$0^{\circ}C$에서 3일간 배양하였을 때 305.0 unit/ml의 xylanase 활성도를 나타내었다. 본 균주는 xylan, 가용성 전분, 볏짚 분말, Avicel, maltose, 그리고 lactose를 유일한 탄소원으로 사용하였을 때 xylanase를 생산하였으나 glucose, xylose, 그리고 arabinose를 사용하였을 때는 xylanase를 생산하지 않았다. 여러 가지 기질들에 대한 배양 상징액의 분해 활성을 조사한 바, xylan 분해 활성 외에 Avicel, carboxymethyl cellulose, 그리고 전분 및 PNPX에 대한 분해 활성은 나타내지 않았다. Xylanase 합성은 glucose에 의해서는 억제되었으나 xylose에 의해서는 억제되지 않았다. 배양 상징액을 이용한 xylan 분해 산물은 xylobiose를 포함한 소당류들이었으며 xylose는 거의 생성되지 않았다.

• 한국균학회지
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• 제26권1호통권84호
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• pp.39-46
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• 1998

꽃송이 버섯의 균사생장은 $25^{\circ}C$의 온도와 pH4의 조건에서 가장 양호하였으며, Hamada 배지에서 가장 조밀한 생장을 나타낸 반면, Hoppkins 배지에서 가장 큰 직경생장을 나타내었다. Maltose, Arabinose 및 Mannitol 같은 탄소원은 꽃송이 버섯의 양호한 생장을 촉진하였다. 또한, 질소원의 하나인 Glycine도 양호한 균사생장을 나타내었다. 배지에 탄소원을 1%로 고정시킨후 C/N비를 20:1로 하였을 때, 꽃송이 버섯 균사의 생장이 가장 양호하였다. 유기산으로서 Fumaric acid와 Lactic acid의 처리를 하였을 때, 꽃송이 버섯의 생장이 좋았다.

• 한국미생물·생명공학회지
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• 제23권5호
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• pp.506-512
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• 1995

A cell aggregation factor produced by Aspergillus sp. LAM 94-142 was purified and partially characterized. The factor was purified about 15 folds from culture broth by IRA 420 and IRC 120 treatment, 1% NaCl added acetone precipitation, and Sepharose 4B column chromatography with overall yield of 48%. It was heteropolysaccharide consisted of mannose, arabinose, and glucose with a molar ratio, 31:17:2, and its molecular weight was estimated to be about 900,000 daltons by Sepharodse 4B gel filtration method. The optimum pH and temperature was 8 and 40$\circ$C, respectively. The factor was stable in pH range of 3-9 and at 100$\circ$C for 90 min. The cell aggregation activity of the factor was inhibited by the addition of Hg$^{2+}$, Fe$^{2+}$, Cu$^{2+}$, and some polypeptides such as milk casein or hemoglobin. The factor aggregated Bacillus subtilis, B. macerans, B. turingiensis, E. coli, Peudomonas aeruginosa, P. fluorescens, P. malophilia, and weakly aggregated Staphylococcus sp., Sarcina lutea, P. putida and Cryptococcus neoformnans, but it didn't aggregate various strains of Candida sp. and Saccharomyces sp.