• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2005년도 생물공학의 동향(XVII)
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• pp.495-495
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• 2005

• 한국식생활문화학회지
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• 제5권2호
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• pp.243-251
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• 1990

두릅나무 순의 saponin을 추출하여 그 구조를 밝혀 본 결과는 다음과 같다. 1. 자연산 날 것 식용적기의 crude saponin에서 aglycon으로 oleanolic acid와 hederagenin외에 1,3-methylenedioxy-3-dehydroxyoleanolic acid를 동정하였으며 당으로 ${\alpha},\;{\beta}-glucose$와 arabinose, rhamnose를 확인하였다. 2. 자연산 날 것 식용적기에 가장 많은 ‘b’ saponin(elatoside $Fh_2$)을 분리하여 동정한 결과 그 구조는 3-0-$[{\alpha}-L-arabinopyranosyl(1{\rightarrow}2)-{\beta}-D-glucopyranosyl]$-28-O-${\beta}-D-glucopyranosyl$ oleanolic acid라 추정된다.

• Journal of Microbiology and Biotechnology
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• 제6권3호
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• pp.179-183
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• 1996

Synergism among endo-xylanase, $\beta$-xylosidase, and $\alpha$-L-arabinofuranosidase from Bacillus stearothermophilus upon xylan hydrolysis was investigated by using birchwood, oat spelt, and arabinoxylan as substrates. Endo-xylanase and $\beta$-xylosidase showed the cooperative action on all three substrates tested, revealing the fact that $\beta$-xylosidase assists endo-xylanase action in xylan hydrolysis by relieving the endproduct inhibition upon endo-xylanase conferred by xylooligomers. $\alpha$-L-Arabinofuranosidase also exhibited synergic effects with endo-xylanase and $\beta$-xylosidase on oat spelt and arabinoxylan, which contained significant amounts of arabinose side chains, whereas no synergism was detected on birchwood xylan which had only trace amounts of the side chain. Thus, the hydrolysis of xylan containing arabinose side chains required $\alpha$-L-arabinofuranosidase as well as endo-xylanase and $\beta$-xylosidase for the better hydrolysis of the substrates, and these enzymes work cooperatively in order to maximize the extent and rate of xylan hydrolysis.

• Journal of Microbiology and Biotechnology
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• 제10권3호
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• pp.321-326
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• 2000

To examine the feasibility of the long-term production of the human granulocyte colony stimulating factor (hG-CSF) using the $_{L}-arabinose$ promoter system of Escherichia coli, flask relay culture and cyclic fed-batch culture were performed. In the flask relay culture, it was found that the pismid was maintained stably up to about 170 generations in an uninduced condition, whereby the cells could also maintain the capability of expressing hG-CSF expression were maintained stably up to at least 100 generations. In contrast, in the cyclid fed-batch culture, segregational plasmid instability was observed within about 4 generations after induction, even though the cell growth and hG-CSF production reached their maximum balues, 78.0 g/l of dry cell weight and 7.0 g/l of hG-CSF, respectively. It would appear that, when compared to the flask relay culture, the high-cell density and high-level expression of hG-CSF in the cyclic fed-batch cultrure led to the segregational plasmid instability; in other words, a severe metabolic burden existe on the cells due to the high-level expression of hG-CSF. Accordingly, based on these long-term cultures, the segregational and structural plasmid instability was observed and a strategy to overcome such problems could be designed.

• Journal of Microbiology and Biotechnology
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• 제18권3호
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• pp.434-442
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• 2008

We observed that an inclusion body (IB) of recombinant ${\beta}$-galactosidase that was produced by the araBAD promoter system in Escherichia coli (E. coil) showed enzyme activity. In order to improve its activity, the lowering of the transcription rate of the ${\beta}$-galactosidase structural gene was attempted through competition between an inducer (L-arabinose) and an inducer analog (D-fucose). In the deep-well microtiter plate culture and lab-scale fermentor culture, it was demonstrated that the addition of D-fucose caused an improvement in specific ${\beta}$-galactosidase production, although ${\beta}$-galactosidase was produced as an IB. In particular, the addition of D-fucose after induction led to an increase in the specific activity of ${\beta}$-galactosidase IB. Finally, we confirmed that the addition of D-fucose after induction caused changes in the structure of ${\beta}$-galactosidase IB, with higher enzyme activity. Based on these results, we expect that an improved enzyme IB will be used as a biocatalyst of the enzyme bioprocess, because an enzyme IB can be purified easily and has physical durability.

• 대한임상검사과학회지
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• 제37권1호
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• pp.27-34
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• 2005

Biochemical characteristics, enterotoxin production and antimicrobial susceptibility were determined for 30 strains of Bacillus cereus isolated from stool specimens of diarrhea patients at an university hospital in Chulabuk-do province. Positive rate for VP reaction and citrate utilization were lower, (33 % and 40 % respectively) while the rates of acid production from mannitol, arabinose, and xylose were higher (17 %, 13 % and 3 % respectively) than those obtained by other investigators. The enterotoxin gene was detected in 18 of 30 isolates (60 %) by PCR, and the toxin was detected from all of the toxin gene-positive isolates by RPLA test. The agar dilution test showed that all isolates were resistant to penicillin G and 73 % were to cephalothin, but all were susceptible to ciprofloxacin, clindamycin, erythromycin, fusidic acid, gentamicin, rifampin, teracycline and vancomycin. We conclude that B. cereus isolates producing acid from mannitol, arabinose and xylose exist, that PCR can be used to detect enterotoxin genes rapidly and accurately, and that this organism is susceptible to various antimicrobial agents though not penicillin G and cephalothin.

• 한국미생물·생명공학회지
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• 제24권3호
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• pp.336-343
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• 1996

Maximum amount of the aminopeptidase M inhibitors produced by Streptomyces griseoplanus SL20209 in 500 ml-Erlenmeyer flask was accumulated after cultivation for 3 days at 28$\circ$C, thereafter the amount of inhibitors decreased slowly with a pH change to alkaline. Arabinose, xylose, mannose and soluble starch were good carbon sources for the production of the inhibitors. On the other hand, glucose was only good for the cell growth but potently inhibited the production of inhibitors. Natural organic nitrogen sources such as soybean meal, fish meal, gluten meal and peanut powder were good for the production of inhibitors, however, soytone, peptone and inorganic nitrogens such as NH$_{4}$C1 and NH$_{4}$NO$_{3}$ were poor. Inclusion of yeast extract (0.5%, w/v) or K$_{2}$HPO$_{4}$ (0.05%) into the production medium increased the production of inhibitors by accelerating cell growth. The production of inhibitors was slightly increased on the medium containing CaCO$_{3}$ (0.3%) and zeolite (0.5%), respectively. Optimal temperature and initial pH range for the production ot inhibitors were determined to be 28$\circ$C and 6.0-7.0, respectively. Employing two improved production media consisting of 3% arabinose or soluble starch, 2.5% soybean meal, 0.5% yeast extract, 0.05% K$_{2}$HP0$_{4}$, 0.1% CaCO$_{3}$ and 0.3% zeolite (pH 6.8), 1.8-fold increase in the amount of inhibitors was achieved, comparing with the basal medium used.

• 한국미생물·생명공학회지
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• 제14권2호
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• pp.205-208
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• 1986

Bacillus thuringiensis 균주중 23 serovars의 생화학적 특성을 비교 연구하였다. 23개의 혈청성 균주는 모두 그람염색에 양성반응을 나타냈고, 내독소와 아포를 형성하며, KIA배지에서 산과 알칼리를 생산하고, 포도당배지에서 깨스를 생산하며, 전분을 가수분해하고, nitrate을 환원하나, H$_2$S 와 indole을 생산하지 않았고, 또한 lysine, ornithine, phenylalanine, malonate, lactose, dulcitol, adonitol, inositol, sorbitol, arabinose, raffinose, rhamnose, maltose, xylose을 분해치 않고, oridase를 생산하지 않았다. 18 serovars는 MR 검사에서 양성 이였고, 15 serovars는 VP검사에서 양성이였다. 4 serovars 는 citrate을 이용했다. 5 serovars는 포도당 배지에서 산을, 2 serovars는 DNase를, 15 serovars는 lecithinase를 생산했다. 12 serovars는 arginine을, 11 serovars는 sucrose를, 2 serovars는 manitol을, 9 serovars는 salicin을 분해했다. serovar tochigiensis만이 hemolysis를 하지 않았다.

• 한국식품과학회지
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• 제36권1호
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• pp.75-80
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• 2004

본 연구에서는 맛성분과 관능검사자료를 중회귀 분석하여 보리간장 맛을 평가하였다. 단순상관에서는 proline, alanine, methionine, lysine, histidine, lavulinic acid, ${\alpha}$-ketogutaric acid 및 citric acid와 관능검사 점수사이의 상관계수가 유의성이 높은 것으로 나타났으며, threonine, serine, cystein, phenylalanine, succinic acid, arabinose, xylose 및 sucrose 둥의 성분은 관능검사 점수에 거의 상관이 없는 것으로 나타났다. 하지만 단순상관분석으로는 보리간장 맛의 품질을 측정하는 것이 불가능하였다. 중회귀 분석을 실시한 결과 결정계수가 0.93 이상을 나타내어 맛성분 함량과 중회귀식을 이용하여 보리간장 맛의 93%를 추정하는 것이 가능하였다.

• 대한수의학회지
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• 제34권1호
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• pp.99-105
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• 1994

홀스타인 젖소의 분변에서 우세균종으로 분리되는 동정불능 Clostridium균주에 대해 당분해 성상검사, 생화학적 성상검사, G+C mol% 측정, 유사 균종과의 DNA-DNA hybridiazation 등을 조사한 결과, 기존의 clostridium균종과는 성상이 일치하지 않는 새로운 신균종(New Species)임이 처음으로 밝혀져, 이 균주를 Clostridium bovis로 분류, 명명하였다. 이 C. bovis는 그램 양성, 운동성의 편성 혐기성 아포형성 간균이었으며, 당분해 성상은 arabinose, xylose, glucose, mannose, fructose, galactose, sucrose, maltose, cellobiose, lactose, trehalose, melibiose, raffinose, inulin, salicin을 분해하였다. Gas chromatography를 사용하여 PYFG broth로부티의 최종대사산물(End products)를 측정한 결과, 다량의 butyric, lactic acid와 소량의 acetic, succinic acid를 생산하였다. C. bovis의 Type strain은 Catt $66^T$이며, G+C mol%는 26 mol%이 었다.