• 한국수산과학회지
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• 제47권1호
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• pp.31-38
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• 2014

Docosahexaenoic acid (DHA, 22:6n-3) and ecosapentaenoic acid (20:5n-3) have attracted increasing attention since the first epidemiological report on the importance of n-3 essential fatty acids. It is thought that DHA has important functions in brain and retinal tissues. Thraustochytrids, a group of marine protists, are capable of heterotrophic growth, and are potential omega-3 producers for industrial use, especially the members of the Schizochytrium and Thraustochytrium genera. The aims of this work were to isolate, identify and screen thraustochytrids from 17 different locations. Twenty-three isolates were screened for biomass, total fatty acid (TFA) and DHA content. Analysis of the fatty acid methyl esters revealed four distinct clusters biomass ranged from $8.68-9.36gL^{-1}$, and lipid and DHA contents ranged from $3.11-4.10gL^{-1}$ and $1.05-1.93gL^{-1}$ biomass, respectively. B-12 isolates were screened for biomass ($9.36gL^{-1}$), TFA ($4.10gL^{-1}$) and DHA (47.01%, w/w) content. C-6 isolates were also screened for biomass ($8.92gL^{-1}$), TFA ($3.30gL^{-1}$) and DHA (49.41%, w/w) content. The 18S rRNA gene sequencing results identified Schizochytrium mangrovei as B-12 and Crypthecodium cohnii as C-6.

• Biotechnology and Bioprocess Engineering:BBE
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• 제5권3호
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• pp.181-185
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• 2000

A marine microorganism, strain 96CJ10356 produced exopolysaccharide, designated as EPS-R. To optimize culmize culture conditions for the production of EPS-R, carbon and nitrogen sources, mineral salts, temperature, and pH were exmined. From this study, STN medium for the production of EPS-R was suggested as follows; sucrose 20g, typtone 10g, NaCl 10g, MgSO45g, CaCl21g, KH2PO4 76mg, K2HPO4 83mg, FeCl2 5mg, MnCl2 1mg, NaMoO4 1mg, and ZnCl2 1mg per liter at pH 7.0. About 9.23g/L of EPS-R was obtained from STN medium after cultivation for 120h at $25^{\circ}C$ in a 5-liter jar fermentor with an aearation rate of 0.17 vvm. Apparent viscosity and flocculation activity of the culture broth were increased with the production of EPS-R and the maximal values were 415 cP and 1400 unit/mL against 0.5% activated carbon, respectively.

• 한국수산과학회지
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• 제47권2호
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• pp.144-153
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• 2014

Both docosahexaenoic acid (DHA, 22:6n-3) and eicosapentaenoic acid (EPA, 20:5n-3) have attracted increasing attention since the first epidemiological report on the importance of n-3 essential fatty acids. Lipids in microbial cells play various biological roles and, consequently, much research has been carried out on their role in cell physiology. The lipid composition of microorganisms can exhibit considerable variations depending on environment. The effects of culture conditions, temperature (15, 20, 24, 28, 32 and $36^{\circ}C$), salinity (10, 20, 30, 40 and 50 psu), pH (pH5, 6, 7, 8 and 9), rotation speeds (50, 100, 150 and 200 rpm), carbon sources, nitrogen sources and C/N ratio on the production of docosahexaenoic acid, fatty-acid profiles, and acids secreted to the broth culture by the oleaginous microorganism, Schizochytrium mangrovei (KCTC 11117BP), were studied. Temperature (initially $28^{\circ}C$), salinity (20 psu), pH (pH7), rotation speeds (100 rpm), organism fatty acids, and secreted acids in the broth were varied during cultivation of S. mangrovei. At pH 7.0, S. mangrovei was able to accumulate lipids up to 40% of its biomass, with 13% (w/w) DHA content. The monosaccharides glucose and fructose, and yeast extract were suitable carbon and nitrogen sources, respectively. The primary omega-3 polyunsaturated fatty acid produced was docosahexaenoic acid.

• Fisheries and Aquatic Sciences
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• 제17권2호
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• pp.215-222
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• 2014

To explore marine microorganisms with medical potential, we isolated and identified marine bacteria from floats, marine algae, animals, and sponges collected from Jeju Island, Korea. We isolated and identified 21 different strains from the marine samples by 16S rRNA analysis, cultured them in marine broth, and extracted them with ethyl acetate (EtOAc) to collect secondary metabolite fractions. Next, we evaluated their anti-oxidative and anti-inflammatory effects. Among the 21 strains, the secondary metabolite fraction of Bacillus badius had both strong antioxidant and anti-inflammatory activity, and thus was selected for further experiments. An antioxidant compound detected from the secondary metabolite fraction of B. badius was purified by preparative centrifugal partition chromatography (n-hexane:EtOAc:methanol:water, 4:6:4:6, v/v), and identified as diolmycin A2. Additionally, diolmycin A2 strongly inhibited nitric oxide production. Thus, we successfully identified a significant bioactive compound from B. badius among the bacterial strains collected from Jeju Island.

• 생명과학회지
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• 제21권8호
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• pp.1083-1093
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• 2011

왕겨를 기질로 사용하여 carboxymethylcellualse (CMCase)를 생산하는 미생물을 해수에서 분리하였으며 16S rDNA의 염기서열을 분석하여 동정한 결과, Bacillus lichemiformis로 확인되었다. CMCase를 생산하기 위한 최적의 탄소원과 질소원은 왕겨와 암모니움 나이트레이트이었다. 통계학적인 방법인 response surface method (RSM)을 사용하여 CMCase를 생산하기 위한 조건을 최적화하였다. 통계학적인 분석 결과, 왕겨가 균체의 생육에 미치는 영향이 가장 높았으며, 왕겨와 배지의 초기 pH가 CMCase 생산에 미치는 영향이 높았다. Design Expert Software를 사용하여 결과를 분석한 결과, 균체의 생장에 최적인 조건은 48.7 g/l 왕겨, 1.8 g/l 암모니움 나이트레이트, 배지의 초기 pH 6.8 및 배양온도 35.7$^{\circ}C$이었으나, CMCase의 생산에 최적인 조건은 43.2 g/l 왕겨, 1.1 g/l 암모니움 나이트레이트, 배지의 초기 pH 6.8 및 배양온도 35.7$^{\circ}C$이었다. 최적화된 조건에서 왕겨를 기질로 사용하여 B. lincheniformis LBH-52가 생산하는 CMCase는 79.6 U/ml이었다. 본 연구를 통하여 왕겨와 암모니움 나이트레이트를 CMCase를 생산하는 기질로 개발하였으며, 해수에서 분리한 미생물을 사용하여 생산기간을 3일로 단축하였다.

• Journal of Microbiology and Biotechnology
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• 제22권10호
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• pp.1412-1422
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• 2012

The aim of this work was to establish the optimal conditions for production of carboxymethylcellulase (CMCase) by a newly isolated marine bacterium using response surface methodology (RSM). A microorganism producing CMCase, isolated from seawater, was identified as Cellulophaga lytica based 16S rDNA sequencing and the neighborjoining method. The optimal conditions of rice bran, ammonium chloride, and initial pH of the medium for cell growth were 100.0 g/l, 5.00 g/l, and 7.0, respectively, whereas those for production of CMCase were 79.9 g/l, 8.52 g/l, and 6.1. The optimal concentrations of $K_2HPO_4$, NaCl, $MgSO_4{\cdot}7H_2O$, and $(NH_4)_2SO_4$ for cell growth were 6.25, 0.62, 0.28, and 0.42 g/l, respectively, whereas those for production of CMCase were 3.72, 0.54, 0.70, and 0.34 g/l. The optimal temperature for cell growth and the CMCase production by C. lytica LBH-14 were $35^{\circ}C$ and $25^{\circ}C$, respectively. The maximal production of CMCase under optimized condition for 3 days was 110.8 U/ml, which was 5.3 times higher than that before optimization. In this study, rice bran and ammonium chloride were developed as carbon and nitrogen sources for the production of CMCase by C. lytica LBH-14. The time for production of CMCase by a newly isolated marine bacterium with submerged fermentations reduced to 3 days, which resulted in enhanced productivity of CMCase and a decrease in its production cost.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 춘계학술발표대회
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• pp.137-140
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• 2000

Marine microorganism strain 96CJ10356 produced exopolysaccharides, designated as EPS-R. To optimize culture conditions for the production of EPS-R, carbon, nitrogen, mineral salt, temperature, and pH were examined. STN medium was suggested as follow; sucrose 20, tryptone 10, NaCl 10, $MgSO_4$ 5, $CaCl_2$ 1, $KH_2PO_4$ 0.0076, $K_2HPO_4$ 0.0083, $FeCl_2$ 0.005, $MnCl_2$ 0.001, $NaMoO_4$ 0.001, $ZnCl_2$ 0.001 (g/1) and pH 7.0 About 9.23 g/l of EPS-R was obtained from the STN medium after cultivation for 120 h at $25^{\circ}C$ in 5-liter jar fermentor with an aeration rate of 0.17 vvm. Apparent viscosity and flocculation activity of the culture broth were increased with the production of the EPS-R and the maximal values were reached to 415 cp and 1400 units/ml against 0.5 % activated carbon, respectively.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2017년도 공동학술발표회
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• pp.188-188
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• 2017

• Applied Biological Chemistry
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• 제36권1호
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• pp.45-50
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• 1993

생선 시료로부터 대두유를 배지원으로 $10^{\circ}C$에서 증식배양하고, 조효소액의 효소활성을 조사하여 대두유 응고활성이 높고 단백질 분해활성이 낮은 호냉성 세균을 최종 선발하여 Pseudomonas sp.로 잠정 동정하였다. 조효소액의 대두유 응고활성은 $20{\sim}60^{\circ}C$에서 관찰되었고 최적온도는 $40^{\circ}C$였으며, 단백질 분해활성의 최적온도는 $40^{\circ}C$였고 $30^{\circ}C$이하 및 $60^{\circ}C$ 이상에서는 단백질 분해활성이 나타나지 않았다. 조효소의 활성은 pH$5.8{\sim}7.3$ 범위에서 pH가 증가함에 따라 감소되었다.

• 환경생물
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• 제21권4호
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• pp.405-409
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• 2003

To study the tolerant capacity of anaerobic granular sludge (AGS) to oxygen using semi -dynamic batch experiment, the aerating time, pH of the basal media, reductive inorganic materials, microorganism, and microorganism metabolite were investigated. When the aerating time was higher or lower than 0.5 h, the producing gas activity of sludge was lower than that of the control. The oxygen tolerance of the experimental sludge was the highest at the initial pH 7.2. The producing gas activity of sludge I was higher than that of sludge II. And storage at $4^{\circ}C$ can low the lose of the oxygen tolerance capacity of granular sludge. The producing gas activity of sludge was the highest when KI was added. The growth of aerobic microorganisms and some metabolite could increase the producing gas activity of granular sludge.