• 한국미생물·생명공학회지
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• 제30권3호
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• pp.264-269
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• 2002

Zoogloea ramigera l15SLR로부터 zooglan다당류의 생산을 위한 최적조건에 관한 연구를 수행하였다 탄소원으로 2.5%의 glucose와 lactose를 이용하였을 때 각각 10.7, 10.5 g/L의 다당류를 생산하였으며 , galactose, white sugar, brown sugar의 경우는 각각 6.4, 6.7, 8.7 g/L의 다당류 생산 을 보였다. 2.5% glucose가 첨가된 제한배지에서 종균 배양액(TSB 배지)을 7ml 이상 접종함으로서 종균 1 ml를 접종 하석 생산된 다당류(2.37 gt) 보다 약 4배의 높은 다당류 생산(10.28 g/L)을 보였다. 종균 배양액을 5 ml이상 접종시에 배양 36시간 이후부터 다당류를 생산하였으며 48시간 배양시에 10g/L이상의 다당류 생산이 가능하였다. 탄소원으로서 또한, 종균 배양액의 흡광도가 1.0~l.7일 경우에 10g/L 이상의 다당류를 생산하였으며, 이 범위를 벗어나는 경우에는 다당류 생산이 저해되었다. 배양액에 rifampicin첨가는 12 g/L이상의 다당류 생산을 보였으며, 다당류 분자량은 1.367$\times$106(g/mol)로서 rifampicin을 가하지 경우 1.711$\times$106(g/mol)와 약간의 차이를 보였다.

• Journal of Microbiology and Biotechnology
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• 제18권1호
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• pp.67-73
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• 2008

The potential of the exopolysaccharide (EPS) from a Serratia sp. strain Gsm01 as an antiviral agent against a yellow strain of Cucumber mosaic virus (CMV-Y) was evaluated in tobacco plants (Nicotiana tabacum cv. Xanthi-nc). The spray treatment of plants using an EPS preparation, 72h before CMV-Y inoculation, protected them against symptom appearance. Fifteen days after challenge inoculation with CMV-Y, 33.33% of plants showed mosaic symptoms in EPS-treated plants compared with 100% in the control plants. The EPS-treated plants, which showed mosaic symptoms, appeared three days later than the controls. The enzyme-linked immunosorbent assay (ELISA) and reverse transcriptase polymerase chain reaction (RT-PCR) analyses of the leaves of the protected plants revealed that the EPS treatment affected virus accumulation in those plants. Analysis of phenylalanine ammonia lyase, peroxidase, and phenols in protected plants revealed enhanced accumulation of these substances. The pathogenesis-related (PR) genes expression represented by PR-lb was increased in EPS-treated plants. This is the first report of a systemic induction of protection triggered by EPS produced by Serratia sp. against CMV-Y.

• Journal of Microbiology and Biotechnology
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• 제28권8호
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• pp.1282-1292
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• 2018

The exopolysaccharide (EPS) produced by Bacillus amyloliquefaciens GSBa-1 was isolated and purified by ethanol precipitation, and DEAE-cellulose and Sepharose CL-6B chromatographies. The molecular mass of the purified EPS was determined to be 54 kDa. Monosaccharide analysis showed that the EPS was composed of predominantly glucose, and it was further confirmed by NMR spectroscopy to be ${\alpha}-glucan$ that consisted of a trisaccharide repeating unit with possible presence of two ${\alpha}-(1{\rightarrow}3)$ and one ${\alpha}-(1{\rightarrow}6)$ glucosidic linkages. Microstructural analysis showed that the EPS appeared as ellipsoid or globose with a smooth surface. The EPS had a degradation temperature at $240^{\circ}C$. Furthermore, the EPS had strong DPPH and hydroxyl radical scavenging activities, and moderate superoxidant anion scavenging and metal ion-chelating activities. This is the first characterization of a glucan produced by B. amyloliquefaciens with strong antioxidant activity. The results of this study suggest the potential of the EPS from B. amyloliquefaciens GSBa-1 to serve as a natural antioxidant for application in functional products.

• Journal of Microbiology and Biotechnology
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• 제6권5호
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• pp.321-325
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• 1996

Mutants having altered levels and/or types of EPS in exopolysaccharide biosynthesis were isolated after NTG mutagenesis of Zoogloea ramigera 115SLR. Mutant candidates were classfied with five groups based on the observed characteristics for EPS biosynthesis pattern. The recombinant plasmids pLEX3BS and pLEX3BM were constructed from pEX3B which was previously isolated from genomic DNA of Z. ramigera 115SLR. Plasmid pLEX3BM with a 7.8 kb insert DNA contains an additional 1.8kb DNA fragment which is not present in pLEX3BS containing 13 kb insert DNA. Plasmid pLEX3BM was able to complement the mutation responsible for the changes in morphology of Z. ramigera 115SLR. However, the complementation of EPS negative mutant strains was not successful with pLEX3BM. Plasmid pLEX3BS on the other hand complemented the mutation responsible for the loss of EPS biosynthesis, resulting in the restoration of Z. ramigera 115SLR phenotype. But this plasmid was not able to complement the morphological mutant strain, Z. ramigera 115SLR.

• 미생물학회지
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• 제45권4호
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• pp.324-331
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• 2009

능이버섯(Sarcodon aspratus)의 무름병소에서 분리한 MK1 균주는 절대호기성 타가영양 세균으로 거식세포의 활성을 유도하는 균체외다당류를 다량 생산한다. MK1의 최적 성장 조건과 MK1이 생산하는 균체외다당류의 몇가지 물리적 성질을 알아보았다. MK1은 glucose, galactose, fructose, sucrose를 탄소원으로 잘 이용하나 MK1의 lactose 이용은 다소 저조하였다. 한편 potato starch와 dextrin을 이용하지 못하였다. MK1은 pH 7.0, $30^{\circ}C$, 200 rpm, 2% glucose, 0.05~0.2% $(NH_4)_2SO_4$에서 최적 성장을 보였다. 최적 성장조건에서 얻은 균체외다당류($EPS_{opt}$)는 탄소(37.1%), 질소(2.2%), 산소(49.3%), 수소(6.4%)로 구성되었으며, 황(S)은 검출되지 않았다. 그리고 아미노당과 산성 당을 함유한 이종다당류로 여겨지며, SDS-polyacrylamide gel elctrophoresis로 분석한 $EPS_{opt}$의 분자량은 14.8~47.9 kDa였다. Glucose 배지에서 생산된 균체외다당류($EPS_{glu}$)의 점도를 측정한 바, pH 6.0과 7.5에서 얻은 것들(0.1 g/ml)의 상대 점도($\acute{\eta}_{rel}$)는 각각 1.23과 1.39이었다. 또한 형태 또는 질감에도 차이가 있었는데, 배지의 pH가 낮을수록 미세결정형을, pH가 높아질수록 끈끈한 질감을 보였다. 따라서 배지 pH가 균체외다당류의 물리적 성질에 영향을 주는 것으로 사료된다.

• Journal of Microbiology and Biotechnology
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• 제14권4호
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• pp.872-876
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• 2004

The plant pathogen Erwinia pyrifoliae was infected with bacteriophage PEa1(h), which produced a translucent halo plaque when grown on a lawn of E. pyrifoliae. To investigate the function of an exopolysaccharide (EPS)-depolymerase in the growth of E. pyrifoliae, an EPS-depolymerase gene was synthesized using the PCR method and sequenced. The synthesized gene was then transferred to E. pyrifoliae. The transformed E. pyrifoliae did not produce any ooze, and its growth was inhibited. However, the EPS-depolymerase did not appear to induce cell death. Accordingly, the present results suggest that an EPS-depolymerase may be effective in inhibiting the cell growth or infection of the pathogen E. pyrifoliae.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 춘계학술발표대회
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• pp.211-214
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• 2000

Marine Microorganism strain 96CJ10356 produced extracellular polysaccharide (EPS-R) accompanied with cell growth. To improve the production of EPS-R, the effect of aeration rate was tested in a 5-liter jar fermentor with STN medium. The production of EPS-R was increased with aeration rate and after 72 hour cultivation, 12.20 g/l of EPS-R was obtained with an aeration rate of 1.5 vvm and the apparent viscosity was measured to be about 1000 cp with culture broth.

• Journal of Microbiology
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• 제40권4호
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• pp.260-266
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• 2002

Bacterial strains were isolated from biofilms formed on glass slides submerged in seawater in Dae-Ho Dike. Eight strains showing fast attaching ability were selected and identified. Their exopolysaccharide (EPS)-producing ability and EPS properties were characterized. Based on Microlog System, 4 among the 8 strains were identified as Micrococcus luteus and the rest were Bacillus thuringiensis, Bacillus megaterium,, Staphylococcus saprophyticus and Agrobacterium vitis. A, vitis was reidentified as Sulfitobacter pontiacus based on 16S rDNA sequence data. The amount of water-soluble EPS produced by the 8 strains ranged from 0.114 to 1.329 g$.$l$\^$-1/ and the productivity was negatively correlated with the cell biomass. The molecular weight of the produced EPS ranged from 0.38 to 25.19$\times$10$\^$4/ Da. Glucose and galactose were ubiquitous sugar components. Mannose, ribose, and xylose were also major sugar components. The molecular weight and composition of the EPS showed strain-specific variation.

• Journal of Microbiology and Biotechnology
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• 제9권6호
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• pp.820-825
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• 1999

A bacterial strain WN9, which produced a new type of extracellular polysaccharide, was isolated from soil samples. By morphological, physiological, biochemical, and phylogenetic studies, strain WN9 was identified as a Paenibacillus sp. and it was named as Paenibacillus sp. WN9, which produced a high molecular extracellular polysaccharide from glucose. The molecular weight of the exopolysaccharide (EPS-WN9) was estimated to be about 31.5 mega-Da. The FT-IR spectrum of EPS-WN9 revealed typical characteristics of polysaccharides. EPS- WN9 consisted of D-glucose and D-mannose with a molar ratio of 1:1.4 being identified as a neutral sugar component. The acidic component of EPS- WN9 was tyrosine. Rheological analysis of EPS- WN9 revealed that the pseudoplastic property and its apparent viscosity remained stable at various temperatures and pHs.

• 생명과학회지
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• 제25권6호
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• pp.709-714
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• 2015

본 연구에서는 다양한 식품원으로부터 7종류의 프로바이오틱스를 분리하여 16S rDNA 염기서열 분석을 통해 동정하였으며, 그 결과 Bacillus sp.와 Lactobacillus sp.로 확인되었다. 먼저 LPS로 활성화 된 RAW 264.7 세포주에 7종의 균주 배양액을 처리한 후, nitric oxide (NO) 생성을 측정하였다. 처리한 균주의 배양액 중 Bacillus sp. FG-1과 Lactobacillus sp. FG-6 균주의 배양액 처리군에서 현저하게 NO 생성이 저해되었다. 또한, 이들의 처리에 의해 COX-2, iNOS 그리고 TNF-α와 같은 pro-inflammatory 유전자의 발현이 감소되었다. 균주가 생산하는 여러 물질중 exopolysaccharide (EPS)가 항염증 활성과 관련이 있는지를 검증하기 위하여 두 균주로부터 EPS를 분리하여, 이들이 NO 생성에 미치는 영향을 연구하였다. 그 결과, 두 균주가 생산하는 EPS가 NO 생성을 농도의존적으로 저해하였고, pro-inflammatory 유전자의 발현도 현저하게 감소시켰다. 이러한 연구결과는 EPS가 프로바이오틱스가 생산하는 여러 물질 중 항염증 활성의 핵심물질 중의 하나가 될 수 있음을 시사한다.