• 산업식품공학
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• 제14권3호
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• pp.263-270
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• 2010

Xylanase를 생산하는 호알칼리성 균주를 토양으로부터 분리하여 동정하였다. 토양으로부터 분리한 호알칼리성 균주 3000여종 중 xylanase 활성이 가장 높은 균주인 strain DK-2386 균주를 선별하였다. Gram 염색과 SEM을 통한 형태학적 특성을 관찰하였으며, Methods for General and Molecular Bacteriology와 Bergey's manual of systematic bacteriology, 그리고 Biochemical tests for identification of medical bacteria에 준하여 생화학적 특성을 확인한 결과 배양액의 색은 붉은 빛을 나타내었으며, Gram양성 간균, 내생포자형성, catalase 양성, oxidase 양성, 혐기성 양성, glucose로부터 gas 형성 양성, casein 가수분해 양성, starch 가수분해 양성, CMC 가수분해 양성, xylan 가수분해 양성, nitrate 환원능 양성이며 10% NaCl 농도에서도 생육하는 것을 확인하였다. 균체의 지방산 조성 분석 결과 $C_{15:0\;ISO}$ 27.35%와 $C_{15:0\;ANTEISO}$ 31.54%, $C_{16:0}$ 9.70%로 이루어져 Bacillus속으로 동정되었으며, 16S rDNA 염기서열 분석결과 B. agaradhaerens와 100%의 유사성을 갖는 것을 확인하였다. (사)한국종균협회로부터 분양받은 Bacillus agaradhaerens 40952, B. alcalophilus와 strain DK-2386 균주사이의 생화학적 특성을 비교한 결과 B. agaradhaerens와 속과 종이 같으나 미세하게 특성이 다른 균주로 판단되어 B. agarad haerens DK-2386이라 명명하였다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 춘계학술발표대회
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• pp.562-565
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• 2000

pH 및 온도에 동시에 민감한 하이드로젤을 maleilated chitosan과 N-isopropylacrylamide를 이용하여 합성하였으며, 합성된 하이드로젤은 NIPAAm의 양에 관계없이 비슷한 pH 민감성을 나타내었으며 부피상 전이온도는 모두 NIPAAm의 LCST의 온도인 $32^{\circ}C$부근에서 나타났다. 반면에 MC의 양을 소량 첨가한 하이드로젤은 그만큼 pH의 민감성이 떨어졌다. lysozyme에 의한 MC의 생분해는 2시간이내에 80%가 분해되었다. 또한 indomethacin을 이용한 약물방출 실험에서는 제조된 하이드젤이 방출제어형 약물전달체로서 좋은 결과를 보인 제형으로 관찰되었다.

• Toxicological Research
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• 제15권1호
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• pp.47-53
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• 1999

The effects of methidathion on humoral immune response were studied in BALB/c mice. 0.5 or 5.0 mg/kg/day methidathion were administered orally for 14 days. The parameters examined to assess apparent toxicity of methidathion included changes of body weight, relative weight of spleen, thymus, sidney and liver, and viable spllenic cell numbers. To evaluate the humoral immune response, thymus, kidney and liver, and viable splenic cell numbers. To evaluate the humoral immune resopnse, the plaque forming cell(PFC) responses sheep the red blood cells (SRBC) and the lovels of serum IgG to hen egg lysozyme (HEL) were determined. No alterations were observed in changes of body weights, relative organ weights and the numbers of viable splenocytes by exposure to any dose of methidathion. At the dose of 0.5mg/kg only PFC response was decreased, whereas both PFC response and the level of serum IgG were decreased significantly at the dose of 5.0 mg/kg. These results indicate that exposure to methidathion may cause sup[pression of humoral immune reponse in mice without overt changed in lymphoid organ weight or viability of splenocytes.

• BMB Reports
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• 제34권4호
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• pp.310-315
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• 2001

The uneven distribution of acidic and basic chitinases in different parts of rice seed, and also the characterization of hull-specific chitinases, are reported here. After extraction of chitinases from polished rice, bran, and rice hulls, the chitinases were separated into acidic and basic fractions, according to their behavior on an anion exchanger column. Both fractions from different parts of rice seed showed characteristic activity bands on SDS-PAGE that contained 0.01% glycol chitin. The basic chitinases from rice hulls were further purified using chitin affinity chromatography. The chitinase, specific to rice hulls (RHBC), was 88-fold purified with a 1.3% yield. RHBC has an apparent molecular weight of 22.2 kDa on SDS-PAGE. The optimal pH and temperature were 4.0 and $35^{\circ}C$, respectively. With [$^3H$]chitin as a substrate, RHBC has $V_{max}$ of 13.51 mg/mg protein/hr and $K_m$ of 1.36 mg/ml. This enzyme was an endochitinase devoid of ${\beta}$-1,3-glucanase, lysozyme, and chitosanase activities.

• Fisheries and Aquatic Sciences
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• 제20권6호
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• pp.11.1-11.8
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• 2017

Juvenile black sea bream, Acanthopagrus schlegelii, were exposed to waterborne zinc (Zn) at concentrations of 0, 200, and $400{\mu}g/L$, at temperatures of 18 or $26^{\circ}C$ for 4 weeks. Superoxide dismutase (SOD) activities in the liver and gill of A. schlegelii significantly increased following exposure to waterborne Zn. Significant reduction in glutathione S-transferase (GST) activity in the liver and gill was observed following exposure to waterborne Zn. Glutathione (GSH) concentrations in the liver and gill also significantly decreased following exposure to waterborne Zn. Phagocytosis and lysozyme in the plasma and kidney were significantly increased following exposure to waterborne Zn. High water temperature increased alterations in the antioxidant and immune responses. The results of the present study suggest that waterborne Zn induced significant alterations in oxidative stress, increased immune responses and high temperature that trigger Zn toxicity.

• 한국미생물·생명공학회지
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• 제22권2호
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• pp.143-151
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• 1994

In the course of the study on strain inprovement by protoplast fusion, Lactobacillus acidophilus 88 protoplasts production and regeneration conditions were investigated. This strain produced a bacteriocin that revealed strong inhibitory activity against various indicator strains, especially L. helveticus CNRZ 1096. Protoplasts of L. acidophilus 88 strains were very efficiently obtained by treatment with 125 $\mu $g/ml lysozyme in a protoplast forming buffer containing 20 mM N-2 hydroxy-ethtl-piperazine-N'-2-ethane-sulfonic acid(HEPES, pH 7.0) and 1M sucrose at 37$\circ $C for 30 min. Hovever, treatment with mutanolysin was not effective for the production of L. acidophilus 88 protoplasts under the same conditions. High protoplast yield was obtained form the cells at the middle to late logarithmic growth phase in the de Man, Rogosa and Sharpe(MRS) medium. Regeneration was efficiently accomplished with the MRS medium containing 10% sucrose.

• 약학회지
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• 제37권2호
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• pp.149-157
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• 1993

Protein methylase inhibitor which is a modulator of biological methylation has been purified and characterized from porcine liver soluble fraction by cell fractionation, Sephadex G25 chromatography, reverse phase HPLC, size exclusion HPLC. The results are summarized as follows. 1) The purified inhibitor shows apparent homogeneity, as judged by HPLC. 2) A molecular weight of the purified inhibitor which is composed of 18 amino acid residues is about 1,400 daltons. 3) A single absorption peak of ultraviolet spectrum was observed at 260nm. 4) The inhibitor was not inactivated by heating at $100^{\circ}C$ until 60min. and its activity was not influenced by treatment with digestive enzymes, such as trypsin, pepsin, pronase, chymotrypin, lysozyme, DNase, and RNase. 5) The purified inhibitor inhibited protein rnethylase I, II, III and phospholipid methyltransferase activities. 6) The purified inhibitor inhibited noncompetitively protein methylase II from porcine liver, spleen, and testis. 7) The $K_{i}$ values for protein methylase II from porcine liver, spleen, and testis were 300nM, 250nM, 297nM, respectively.

• Bulletin of the Korean Chemical Society
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• 제25권12호
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• pp.1917-1923
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• 2004

Although the proteolytic activity of the Cu(II) complex of cyclen (Cyc) is greatly enhanced upon attachment to a cross-linked polystyrene (PS), the Cu(II)Cyc-containing PS derivatives reported previously hydrolyzed only a very limited number of proteins. The PS-based artificial metalloproteases can overcome thermal, mechanical, and chemical instabilities of natural proteases, but the narrow substrate selectivity of the artificial metalloproteases limits their industrial application. In the present study, artificial metalloproteases exhibiting broad substrate selectivity were synthesized by attaching Cu(II)Cyc to a PS derivative using linkers with various structures in an attempt to facilitate the interaction of various protein substrates with the PS surface. The new artificial metalloproteases hydrolyzed all of the four protein substrates (albumin, myoglobin, ${\gamma}$-globulin, and lysozyme) examined, manifesting $k_{cat}/K_m$ values of 28-1500 $h_{-1}M_{-1}$ at 50 $^{\circ}C$. The improvement in substrate selectivity is attributed to steric and/or polar interaction between the bound protein and the PS surface as well as the hydrophobicity of the microenvironment of the catalytic centers.

• Preventive Nutrition and Food Science
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• 제2권2호
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• pp.101-108
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• 1997

A lactic acid bacterium LAB3113, isolated from traditionally fermented Kimchi was found to produce bacteriocin whose activity was very specific toward lactobacilli and not effective against any other bacteria. Lactobacilli affected by the inhibitory substance included Lactobacillus delbrueckii-lactis, L. johnsonii, L. gsseri, and L. curvatus. Based upon biochemical and physiological characteristics, LAB3113 was classified as Lactococcus lactis, and its bacteriocin was named as lactococcin K3113. Lactococcus lactis. LAB3113 produced bacteriocin at th early stage of growth and the concentration of the bacteriocin did not decrease even after alt stationalry phase. Optimal temperature of bacteriocin production was $25^{\circ}C$ at the initial pH 7.0. Partially purified lactococcin K3113 was completely inactivated by protease, but not affected by lipase, lysozyme and RNase. The bacteriocin was very heat-stable even after autoclaving for 20 min. It was also stable in pH changes, an was not affected by th presence of solvents. lacotococcin K3113 appeared to act in bactericidal mode against L. delbrueckii-lactis ATCC4797. Molecular weight of lactococcin K3113 was calibrated as 10,500 dal by SDS-PAGE an activity staining. Lactococcus lactis LAB3113 had four residential plasmids of 3.7kb, 11.2kb, 15.5kb, and 48kh in molecular sizes. Plasmid profile analysis of mutant strain revealed that 15.5 kb plasmid was re-sponsible for the production of lactococcin K3113 and its immunity to the bacteriocin.

• 한국양식학회:학술대회논문집
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• 한국양식학회 2003년도 추계학술발표대회 논문요약집
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• pp.68-69
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• 2003

The present study was conducted to investigate the effects of dietary supplementation of $\beta$-1,3 glucan and feed stimulants(BAISM) as a feed additive for juvenile olive flounder (Paralichthys olivaceus). Eight experimental diets supplemented with $\beta$-1,3 glucan and feed stimulants at 0%, $\beta$-1,3 glucan 0.05% ＋ Baism 0.45%, $\beta$-1,3 glucan 0.05% ＋ Baism 0.95%, $\beta$-1,3 glucan 0.10% ＋ Baism 0.90%, $\beta$-1,3 glucan 0.10% ＋ Baism 1.90%, $\beta$-1,3 glucan 0.15% ＋ Baism 1.35%, $\beta$-1,3 glucan 0.15% ＋ Baism 2.85% and $\beta$-1,3 glucan 0.30% ＋ Baism 2.70% of diets as a dry-matter(DM) basis were prepared. Three replicate groups of fish averaging 9.2 $\pm$ 0.1g (Mean $\pm$ SD) were randomly distributed in each aquarium as a group of 15 fish and fed one of eight experimental diets for seven weeks. After the feeding trial, $\beta$-1,3 glucan 0.10% ＋ Baism 0.90%, $\beta$-1,3 glucan 0.10% ＋ Baism 1.90% diets had a higher weight gain (WG), feed efficiency(FE), specific growth rate(SGR) and protein efficiency ratio(PER) than did fish fed 0%, $\beta$-1,3 glucan 0.05% ＋ Baism 0.45%, $\beta$-1,3 glucan 0.05% ＋ Baism 0.95%, $\beta$-1,3 glucan 0.15% ＋ Baism 2.85% and $\beta$-1,3 glucan 0.30% ＋ Baism 2.70% (P<0.05). however, there was no significant difference among fish fed $\beta$-1,3 glucan 0.05% ＋ Baism 0.45%, $\beta$-1,3 glucan 0.05% ＋ Baism 0.95%, $\beta$-1,3 glucan 0.15% ＋ Baism 2.85% and $\beta$-1,3 glucan 0.30% ＋ Baism 2.70%(P>0.05). and $\beta$-1,3 glucan 0.10% ＋ Baism 0.90% diets had a higher peak value of CL(Chemiluminescence) and lysozyme activity, than did fish fed the other diets (P<0.05). These results indicated that dietary sipplementation of $\beta$-1, 3 glucan and Baism affected growth, feed efficiency, specific growth rate, protein efficiency ratio, Peak value of CL and Lysozyme activity, and the optimum dietary supplementation level of $\beta$-1, 3 glucan and Baism as a feed additive could be approximately $\beta$-1, 3 glucan 0.10% ＋ Baism 0.90% of diet in juvenile olive flounder (Paralichthys olivaceus).