• Journal of Microbiology
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• v.42 no.4
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• pp.305-314
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• 2004

An exopolysaccharide-producing microalgal dinoflagellate was isolated from a red-tide bloom and des­ignated strain KG03. A bacteria-free culture of strain KG03 was achieved using a modified wash with phototaxis and antibiotic treatment. Combined treatment with neomycin and cephalosporin was the most effective for eliminating the bacteria associated with the microalgae. Strain KG03 was identified as Gyrodinium impudicum by analyzing the ITS regions of the 5.8S rDNA, 18S rDNA, morphological phenotype and fatty acid composition. The exopolysaccharide production and cell growth in a 300-ml photobioreactor were increased 2.7- and 2.4-fold, respectively, compared with that in a flask culture at the first isolation step.

• Journal of Life Science
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• v.15 no.1 s.68
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• pp.15-20
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• 2005

The unstructured model was tested to describe mycelial growth, exopolysaccharide formation, and substrate consumption in submerged mycelial culture of Paeeiliomyees tenuipes C240. The Logistic equation for mycelial growth, the Luedeking-Piret equation for exopolysaccharide formation, and Luedeking­Piret-like equations for glucose consumptions were successfully incorporated into the model. The value of the key kinetic constants were: maximum specific growth rate ${\mu}m,\;0.7281\;h^{-1};$ growth­associated constant for exopolysaccharide production $(\alpha),\;0.1743g(g\;cells)^{-1}$; non-growth associated constant for exopolysaccharide production $(\beta),\;0.0019g(g\;cells)^{-1}\;;$ maintenance coefficient $(m_s),\;0.0572g\;(g\;cells)^{-1}$. When compared with batch experimental data, the model successfully provided a reasonable description for each parameter during the entire growth phase. The model showed that the production of exopolysaccharide in P. tenuipes C240 was growth-associated. The model tested in the present study can be applied to the design, scale-up, and control of fermentation process for other kinds of basidiomycetes or ascomycetes.

• KSBB Journal
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• v.20 no.1 s.90
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• pp.26-33
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• 2005

The effects of carbon sources for exopolysaccharide production during batch cultivation of an Enterobacter sp. isolated from the composter were investigated. The highest amount of exopolysaccharide was obtained when lactose was used as carbon source. Lactose in medium was converted into glucose and galactose. Glucose was metabolized fast and was completely consumed, but about $20\%$ of lactose was accumulated as galactose. On the other hand, enzyme activity was about $350\~450$ unit with the increase of lactose concentration. Thus, it was considered that the exopolysaccharide might be produced in the course of that lactose was hydrolyzed into glucose and galactose by $\beta-galactosidase$ with respect to that enzyme activity on lactose hydrolysis was accorded to the exopolysaccharide production. When glucose and galactose were added to lactose medium, respectively, it could be considered that glucose was as a repressor and galactose was as a inducer for $\beta-galactosidase$ synthesis even though the mechanisms were not elucidated. The increase of lactose concentration was almost ineffective to the specific growth rate $(0.133\~0.151\;hr^[-1})$ but showed the difference in the biomass content. The higher carbon source concentration, the more residual sugar remained. It was assumed that the optimum lactose concentration for exopolysaccharide production was $30\~70g/L.$ On the other hand, it was considered that the nitrogen acted as growth limiting nutrients to the cell growth. In the cases of 30 and 70 g/L of the fixed carbon concentrations, the increase of the nitrogen sources concentration caused a remarkable increase within the range of $0.059\~0.225\;hr^{-1}$ and $0.141\~0.237hr^{-1}$ of the specific growth rate, respectively, while there was no significant difference in biomass.

• KSBB Journal
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• v.10 no.4
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• pp.441-448
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• 1995

Optimized fermentation medium and cultural conditions for the production or exopolysaccharide KS-1 with Bacillus polymyxa KS-1 was following as; 30g g1ucose, 2.59g yeast extract, $2.5g KH_2PO_4, 0.5g NaCl, 0.3g MgSO_4.7H_20, 0.1g CaC0_3 0.05g, FeSO_4.7H_2O, and 0.05g MnS0_4 . 4H_20in 1 liter distilled water. The exopolysaccharide production was influenced by the by the temperature and pH, the optimal conditions for the production of exopolysaccharide KS-1 seemed to be $30^{\circ}C$ and pH 7.0, respectively. About $10.3g/\ell$ of maximum exopolysaccharide was obtained al the initial pH 7.0, $30^{\circ}C$, 2vvm of aeration rate and 400 rpm of impeller speed in a jar fermentor.

• Journal of Industrial Technology
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• v.24 no.B
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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.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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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 the Korean Society of Food Science and Nutrition
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• v.25 no.1
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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.

• Journal of Microbiology and Biotechnology
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• v.17 no.1
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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.

• KSBB Journal
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• v.16 no.6
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• pp.554-561
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• 2001

Immunostimulating exopolysaccharides with anticancer activity produced by Enterobacter sp. SSYL(KCTC 0687BP), isolated from Chinese elm(Ulmus sp.) were investigated. The exopolysaccharide contains molecular weight 100,000 to 1,000,000 Da and total carbohydrates 43.0 to 70.8%, total uronic acid 7.1 7o 12.4%, and total proteins 15.4 to 20.6%. Compositions and contents of sugars in the exopolysaccharides are 10-30% glucose, less than 1% fructose, 10-15% galactose, 8-12% fucose, and 40-70% glucuronic acid. The anticancer immunostimulating activities were examined and proved with regard to both in vitro and in vivo bioassays. In vivo assay, the glycoprotein at the concentration of 0.3 mg/kg showed the best result that median survival time in creased to ca. 138.1% in contrast to control groups.

• Journal of Microbiology and Biotechnology
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• v.31 no.8
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• pp.1144-1153
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• 2021

A released exopolysaccharide (rEPS)-producing strain (LM187) with good acid resistance, bile salt resistance, and cholesterol-lowering properties was isolated from Sichuan paocai and identified as Leuconostoc mesenteroides subsp. mesenteroides. The purified rEPS, designated as rEPS414, had a uniform molecular weight of 7.757 × 10⁵ Da. Analysis of the monosaccharide composition revealed that the molecule was mainly composed of glucose. The Fourier transform-infrared spectrum showed that rEPS414 contained both α-type and β-type glycosidic bonds. ¹H and ¹³C nuclear magnetic resonance spectra analysis showed that the purified rEPS contained arabinose, galactose, and rhamnose, but less uronic acid. Scanning electron microscopy demonstrated that the exopolysaccharide displayed a large number of scattered, fluffy, porous cellular network flake structures. In addition, rEPS414 exhibited strong in vitro antioxidant activity. These results showed that strain LM187 and its rEPS are promising probiotics with broad prospects in industry.