• 한국미생물·생명공학회지
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• 제23권3호
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• pp.269-274
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• 1995

For the screening of a new functional exopolysaccharide, sugar composition and rheological properties of exopolysaccharide produced from Xanthomonas sp. EPS-1 were investigated. The average molecular weight of exopolysaccharide was determined to be approximately 2.l $\times$ 10$^{6}$ dalton. The new exopolysaccharide EPS-1 was composed of mannose, glucose, galactose and gluco- samine. IR analysis showed that the exopolysaccharide EPS-1 was assumed to be polymer with carbohydrates. NMR analysis showed that exopolysaccharide EPS-1 was presumed to be 4 units of sugar and trace of CH$_{3}$ group. Exopolysaccharide EPS-1 solution showed a characteristic of non-Newtonian fluid properties. At the concentration of 1.0%, the consistency index and the flow behavior index were shown at 10.8352 poise-sec and 0.4419, respectively. All dispersions were pseudoplastic fluids described accurately by Power-law model. Exopolysaccharide EPS-1 was highly viscous at low concentration, with good stability over a wide range of pH 5 to 13. The excellent compatibility of exopolysaccharide EPS-1 was represented with salts such as sodium chloride.

• 한국식품영양과학회지
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• 제25권1호
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• pp.53-57
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• 1996

Xanthomonas sp. EPS-1으로부터 생산된 다당류 EPS-1 용액의 농도가 0.04(g/dl)일 때, 비점도는 0.137, 환원 점도는 3.425, 상대점도는 1.137, 고유점도는 3.209임을 알 수 있었다. 겉보기 점도는 온도상슴에 따라 낮아졌으나 다시 온도를 증가하였을때는 서서히 증가하였다. 열처리 후에도 물성은 거의 변화지 않았으며, 응집성은 좋지 않았으나 locust bean gum과의 혼합효과는 우수하였다.

• 산업기술연구
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• 제24권B호
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• pp.171-176
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• 2004

The effects of agitation and aeration for exopolysaccharide(EPS) production through batch cultivation of an Enterobacter sp. isolated from the composter were investigated. During the EPS fermentation under conditions of constant agitation speed from 200 to 900 rpm and constant aeration rate of 0.5-2.5 vvm, the low yields of EPS(4.8-5.2g/L) was observed as the viscosity increase of culture broth. With the stepwise increases in agitation speed and aeration rate, the EPS production and the viscosity of EPS were increased 1.3~1.4 times and 2.3~3.6 times higher than those of the fixed conditions, respectively. Therefore, these stepwise increases were considered as the key operating parameters for enhancing EPS production. The max. EPS(6.8g/L) and viscosity(14,000cp) were obtained when the agitation speed was increased from 300 to 900 rpm for 54hrs at 1.5 vvm.

• IMMUNE NETWORK
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• 제10권6호
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• pp.230-238
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• 2010

Background: The MK1 strain, a novel bacterial isolate from soft-rotten tissue of the Neungee mushroom, produces copious amounts of exopolysaccharide (EPS) in a dextrose minimal medium. This study examined the molecular characteristics and immunomodulatory activity of MK1 EPS. Methods: The EPS in the culture supernatant was purified by cold ethanol precipitation, and characterized by SDS- PAGE/silver staining and Bio-HPLC. The immunomodulatory activities of the EPS were examined using the mouse monocytic cell line, RAW 264.7 cells. Results: The molecular weights of the purified EPS were rather heterogeneous, ranging from 10.6 to 55 kDa. The EPS was composed of glucose, rhamnose, mannose, galactose, and glucosamine at an approximate molar ratio of 1.00 : 0.8 : 0.71 : 0.29 : 0.21. EPS activated the RAW cells to produce cytokines, such as TNF-${\alpha}$ and IL-$1{\beta}$, and nitric oxide (NO). EPS also induced the expression of co-stimulatory molecules, such as B7-1, B7-2 and ICAM-1, and increased the phagocytic activity. The macrophage-activating activity of EPS was not due to endotoxin contamination because the treatment of EPS with polymyin B did not reduce the macrophage-activating activity. Conclusion: The EPS produced from the MK1 strain exerts macrophage-activating activity.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2001년도 추계학술발표대회
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• pp.808-811
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• 2001

The rheological properties of exopolysaccharide(EPS-R) produced by marine bacteria Hahella chjuensis KCTC 2395 was investigated. EPS-R solution showed a characteristic non-Newtonian behavior fluid properties. In aqueose dispersions of EPS-R 1%, consistency index(K) and flow behavior index(n) were 1,410 cp and 0.73. EPS-R solution was pseudoplastic fluid by power-low model. Rheological propertie of EPS-R was found to be influenced by the concentration of salt, pH, temperature and ionic compounds.

• Journal of Microbiology and Biotechnology
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• 제17권1호
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• pp.44-51
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• 2007

Marine bacterial strains were isolated trom coastal regions of Goa and screened for the strains that produce the highest amount of mucous expolysaccharide (EPS). Our screening resulted in the identification of the strain Vibrio furnissii VB0S3 (hereafter called VB0S3), as it produced the highest EPS in batch cultures during the late logarithmic growth phase. The isolate was identified as VB0S3 based on morphological and biochemical properties. Growth and EPS production were studied in mineral salts medium supplemented with NaCl (1.5%) and glucose (0.2%). The exopolymer was recovered from the culture supernatant by using three volumes of cold ethanol precipitation and dialysis procedure. Chemical analyses of EPS revealed that it is primarily composed of neutral sugars, uronic acids, and proteins. Fourier-transform infrared (FT-IR) spectroscopy revealed the presence of carboxyl, hydroxyl, and amide groups, which correspond to a typical heteropolymeric polysaccharide, and the EPS also possessed good emulsification activity. The gas chromatographic analysis of an alditol-acetate derivatized sample of EPS revealed that it was mainly composed of galactose and glucose. Minor components found were mannose, rhamnose, fucose, ribose, arabinose, and xylose. EPS was readily isolated from culture supernatants, which suggests that the EPS was a slime-like exopolysaccharide. This is the first report of exopolysaccharide characterization that describes the isolation and characterization of an EPS expressed by Vibrio surnissii strain VB0S3. The results of the study contribute significantly and go a long way towards an understanding of the correlation between growth and EPS production, chemical composition, and industrial applications of the exopolysaccharide in environmental biotechnology and bioremediation.

• 한국미생물·생명공학회지
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• 제46권1호
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• pp.9-17
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• 2018

The aims of this work were to characterize and determine bioactivities of crude exopolysaccharide (EPS) extract from Bacillus tequilensis PS21 isolated from milk kefir from Kampaeng Petch, Thailand. B. tequilensis PS21 produced 112.1 mg dried EPS/l from initial 80 g/l lactose in modified TSB media at 52 h, with EPS product yield of 8.9 mg EPS/g lactose and specific product yield of 0.3 mg EPS/mg biomass. The FTIR result confirmed EPS to be a protein-bound polysaccharide and SEM analysis showed the morphology to be a grainy appearance with an uneven surface, covered with pores. HPLC analysis determined EPS as a heteropolysaccharide consisting of five sugar units with the following molar ratios; xylose (17.65), glucose (2.54), ribose (1.83), rhamnose (1.23), and galactose (1). Chemical components of this EPS were predominantly carbohydrate at 697.8 mg/g EPS (65%), protein 361.4 mg/g EPS (34%), and nucleic acid 12.5 mg/g EPS (1%). The EPS demonstrated antioxidant activities at 57.5% DPPH scavenging activity, $37.2{\mu}M\;Fe(II)/mg$ EPS and $34.9{\mu}M\;TEAC\;{\mu}M/mg$ EPS using DPPH, FRAP and ABTS assays, respectively. EPS also exhibited anti-tyrosinase activity at 34.9% inhibition. This work represents the first finding of EPS produced by Bacillus sp. from Thai milk kefir which shows potential applications in the production of antioxidant functional foods and whitening cosmetics. However, optimization of EPS production for industrial exploitation requires further study to ascertain the economic potential.

• KSBB Journal
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• 제17권2호
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• pp.169-175
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• 2002

원유로부터 다당류를 생산하는 유산균을 분리, 선발하여 균의 배양조건을 조사하고 Lactobacillus ssp. SCU-M으로 동정, 명명된 최적배지의 탄소원은 galactose 1.5% 첨가시 553 mg/L의 EPS를 생성하였으며 whey의 이용성 검토를 위한 deproteinized whey와 lactic acidified whey를 탄소원으로 사용하였을 때 각각 639, 550 mg/L를 생성하였다. 질소원으로 yeast extract 1.5%, peptone 0.5%를 첨가한 경우 934 mg/L, 미량성분으로 , 0.15% $K_2$HPO, 0.15% 첨가시 1,076 mg/L의 다당 생산성을 나타내었다. 따라서 이들 결과를 종합하여 galactose 1.50%, yeast extract 1.00%, peptone 0.25%, MgSO$_4$, 7$H_2O$ 0.15%, $K_2$HPO$_4$0.15%, tween 80, 0.10%를 적정 배지로 하여 PH 6.5, 배양온도 37$^{\circ}C$에서 배양시 1,680 mg/L의 EPS를 생성하였다.

• 미생물학회지
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• 제46권3호
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• pp.278-285
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• 2010

국내에 자생하는 당귀, 삽주, 쇠무릎, 지모, 황기의 근권토양내 EPS 생성균주의 분포율을 조사한 결과 당귀로부터 분리된 균주의 56%가 EPS 생성 균주로 가장 높은 분포율을 나타내었다. 또한, 당귀 근계 (근권, 근면, 근 내부) 내 EPS 생성 세균의 밀도를 측정한 결과, 근권 토양 내에는 $9.0{\times}10^6$ CFU/$g{\cdot}soil$, 근면에는 $7.0{\times}10^6$ CFU/$g{\cdot}soil$, 그리고, 근 내부에는 $1.4{\times}10^3$ CFU/$g{\cdot}soil$로 확인되어, 다수의 EPS 생성 세균이 분포하고 있음이 확인되었다. 당귀 근권으로부터 분리된 EPS 생성세균은 Alphaproteobacteria (4 strains), Betaproteobacteria (6 strains), Firmicutes (2 strains), Actinobacteria (3 strains), 그리고 Bacteroidetes (1 strain) 계통군에 속하는 균주였다. 근면으로 부터 분리된 EPS 생성세균은 Alphaproteobacteria (7 strains), Betaproteobacteria (3 strains), Actinobacteria (2 strains), Bacteroidetes (3 strains), 그리고 Acidobacteria (1 strain) 계통군으로 나타났으며, 근 내부에서 분리된 EPS 생성세균은 모두 Bacteroidetes 계통군 Chitinophaga에 속하는 특징을 나타내었다. 약초 근권토양으로부터 분리된 EPS 생성세균 112균주중에서 Burkholderia caribiensis DR14 (1,547 mpa.s), Terriglobus sp. DRP35균주(2,136 mpa.s), Rhizobium hainanense SAP110균주(1,680 mpa.s)를 최우수 EPS 생성 균주로 선발하였다. 분리 정제된 EPS를 Bio-LC로 분석한 결과 glucose, galactose, mannose의 중성당과, galactosamine, glucosamine의 아미노당이 나타났다. 특히 Rhizobium hainanense SAP110 균주는 주요 중성당으로 glucose (60-89%)를 그리고 주요 아미노당으로 glucosamine (8.5%)을 생성하는 특징을 나타내었다.

• 한국미생물·생명공학회지
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• 제23권3호
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• pp.263-268
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• 1995

A screening was performed to isolate exoploysaccharide-producing microorganisms, which synthesized specific exopolysaccharide for the substitutive of commercial polysaccharides, from natural sources. Soil bacterium, one of 378 mucoid isolates, was finally selected as potential producer of polysaccharides which made the culture broth very viscous and thus examined in detail for optimal medium composition. Isolated strain was identified as Xanthomonas sp. EPS- 1 from the results of morphological and biochemical characteristics. The composition of optimal medium for exopolysaccharide production was as follows: 50 g sucrose, 1.5 g peptone, 2 g KH$_{2}$PO$_{4}$, 2 g MgSO$_{4}$, -7H$_{2}$O, 3 g NaCl, 0.05 g CaCO$_{3}$, 0.07 g FeSO$_{4}$-7H$_{2}$O and 0.05 g MnSO$_{4}$-7H$_{2}$O in 1 liter of distilled water. From the experiments of temperature and pH dependence, the optimal conditions for exopolysaccharide biosynthesis seemed to be 30$\circ$C and 8.0, respectively. About 14.9 gram of maximum exopolysaccharide per liter was obtained at the initial pH 8.0, 30$\circ$C and 250 rpm in a flask culture. The exopolysaccharide EPS-1 had such potential as an emulsifying agent and a gelling agent in comparision with commercial exopolysaccharide.