• Biotechnology and Bioprocess Engineering:BBE
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• v.9 no.5
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• pp.405-413
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• 2004

The rheological properties of an exopolysaccharide, EPS-R, produced by the marine bacterium Hahella chejuensis strain 96CJ 10356 were investigated. The $E_{24}$ of $0.5\%$ EPS-R was $89.2\%$, which was higher than that observed in commercial polysaccharides such as xanthan gum ($67.8\%$), gellan gum ($2.01\%$) or sodium alginate ($1.02\%$). Glucose and galactose are the main Sugars in EPS-R, with a molar ratio of ${\~}1:6.8$, xylose and ribose are minor sugar components. The average molecular mass, as determined by gel filtration chromatography, was $2.2{\times}10^3$ KDa, The intrinsic viscosities of EPS-R were calculated to be 16.5 and 15.9 dL/g using the Huggins and Kraemer equations, respectively, with a 2.3 dL/g overlap. In terms of rigidity, the conformation of EPS-R was similar to that of caboxymethyl cellulose ($5.0{\times}10^{-2}$). The rheological behavior of EPS-R dispersion indicated that the formation of a structure intermediate between that of a random-coil polysaccharide and a weak gel. The aqueous dispersion of EPS-R at concentrations ranging from 0.25 to $1.0\%$ (w/w) showed a marked shear-thinning property in accordance with Power-law behavior. In aqueous dispersions of $1.0\%$ EPS-R, the consistency index (K) and flow behavior index (n) were 1,410 and 0.73, respectively. EPS-R was Stable to pH and salts.

• Food Science of Animal Resources
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• v.26 no.4
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• pp.532-539
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• 2006

This study was conducted to evaluate the inhibitory effects of exopolysaccharide(EPS) produced by Streptococcus thermophilus BODY1 on rotavirus(RV). EPS was isolated from a commercial lactic acid bacteria, Str. thermophilus BODY1. The results obtained were as follows : At 0.1% of EPS, inhibitory effects of EPS on the MA-104 cell using MTT assay were, $Wa\;51.58{\pm}8.08%,\;KU \;63.09{\pm}7.58%,\;S2\;51.23{\pm}5.43%,\;YO\; 51.45{\pm}5.67%,\;K-21\;52.84{\pm}5.49%,\;NCDV\;57.50{\pm}10.85%,\;UK\;51.64{\pm}4.74%,\;KK3\;54.53{\pm}8.44%,\;JBR\;58.67{\pm}7.51%,\;S97\;50.63{\pm}5.17%,\;OSU\;55.48{\pm}5.75%,\;and\;RRV\;54.36{\pm}8.72%$, respectively. At 0.1/128%, the effects were $Wa\;5.5{\pm}6.45%,\;KU\;10.33{\pm}8.39%,\;S2\;0.98{\pm}8.39%,\;YO\;4.25{\pm}2.86%,\;K-21\;4.25{\pm}6.60%,\;NCDV\;4.01{\pm}4.12%,\;UK\;6.55{\pm}7.09%,\;KK3\;5.19{\pm}4.86%,\;JBR\;11.11{\pm}8.11%,\;S97\;6.75{\pm}6.95%,\;OSU\;10.14{\pm}8.54%,\;and\;RRV\;3.66{\pm}8.57%$, respectively. These results indicate that EPS have inhibitory effects on various serotype and sources of RV from different animals.

• Journal of Mushroom
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• v.6 no.1
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• pp.27-31
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• 2008

The optimization of submerged culture conditions for mycelial growth and exopolysaccharide (EPS) production in an edible mushroom Tremella fuciformis were studied in shake flasks and bioreactors. The temperature of $28^{\circ}C$ and pH 8 in the beginning of fermentation in agitated flasks was the most efficient condition to obtain maximum mycelial biomass and EPS. The optimal medium constituents were as follows (g l-1): glucose 20, tryptone 2, $KH_2PO_4$ 0.46, $K_2HPO_4$ 1 and $MgSO_4H_2O$ 0.5. The fungus was cultivated under various agitation and aeration conditions in a 5L stirred-tank bioreactor. The maximum cell mass and EPS production were obtained at a relatively high agitation speed of 200 rpm and at an aeration rate of 2 vvm. The flow behavior of the fermentation broth was Newtonian and the maximum apparent viscosity (35 cP) was observed at a highly aerated condition (2 vvm). The EPS productivity in an airlift reactor was higher than that in the stirred-tank reactor. The EPS was protein-bound polysaccharides consisted of mainly mannose, xylose, and fructose. The molecular weights of EPS were determined to be $1.3{\sim}1.5{\times}10^6$.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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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.

• 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.

• KSBB Journal
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• v.24 no.3
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• pp.303-311
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• 2009

A scaling up study for the exopolysaccharide (EPS) production by submerged culture of Ganoderma lucidum was carried out in jar fermenter systems (2.6, 20 and 75 L) under bi-staged pH process. Profiles of dissolved oxygen (DO) and volumetric coefficient of oxygen transfer ($k_La$) as a function of operating variables (agitation speed and aeration rate) was investigated, and a correlation between $k_La$ and operating variables was analysed statistically. Under bi-staged pH process, no limitation of DO was observed at agitation speeds tested in the range of 200 and 600 rpm, and the highest EPS production was obtained at the level of DO of $40{\sim}80%$. From the regression analysis, the relation between $k_La$, gas velocity (Vs), stirrer speed (N) and impeller diameter (Di) could be expressed as : $$k_La=0.555{\times}Vs^{0.42}{\times}(N^3{\times}Di^2)^{0.33}\;(R^2=0.925,\;p<0.05)$$ It was found that under 2.6 L jar fermenter, the optimum agitation speed and aeration rate was 400 rpm and 1 vvm, respectively, obtaining the EPS production of 15.43 g/L. Under the submerged cultivation of G. lucidum in jar fermenters of $2.6{\sim}75\;L$, the similar EPS yields at each fermenter were achieved during scaling up based on $k_La$, and $k_La$ value for maximum EPS production was $85.4{\pm}26.70\;h^{-1}$.

• Journal of Microbiology and Biotechnology
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• v.21 no.10
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• pp.1036-1042
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• 2011

The exopolysaccharide botryosphaeran ($EPS_{GLC}$; a ($1{\rightarrow}3$)($1{\rightarrow}6$)-${\beta}$-D-glucan from Botryosphaeria rhodina MAMB-05) was sulfonated to produce a water-soluble fraction ($EPS_{GLC}$-S) using pyridine and chlorosulfonic acid in formamid. This procedure was then repeated twice to produce another fraction ($EPS_{GLC}$-RS) with a higher degree of substitution (DS, 1.64). The purity of each botryosphaeran sample (unsulfonated and sulfonated) was assessed by gel filtration chromatography (Sepharose CL-4B), where each polysaccharide was eluted as a single symmetrical peak. The structures of the sulfonated and re-sulfonated botryosphaerans were investigated using ultraviolet-visible (UV-Vis), Fourier-transform infrared (FT-IR), and $^{13}C$ nuclear magnetic resonance ($^{13}C$ NMR) spectroscopies. $EPS_{GLC}$ and $EPS_{GLC}$-RS were also assayed for anticoagulation activity, and $EPS_{GLC}$-RS was identified as an anticoagulant.

• Microbiology and Biotechnology Letters
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• v.51 no.2
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• pp.157-166
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• 2023

Three lactic acid bacteria (LAB) producing exopolysaccharides (EPSs) were isolated from Pa (green onion)-kimchi, and identified as Weissella confusa (SKP 173), Weissella cibaria (SKP 182), and Leuconostoc citreum (SKP 281), respectively by 16S rRNA gene sequencing. The yields of EPS were 21.27, 18.53, and 15.4 g/l for EPS from SKP 173, 182, and 281, respectively when grown in MRS broth containing sucrose (5%, w/v). Total sugar contents were 64.39, 62.84, and 65.16% (w/w) for EPS from SKP 173, 182, and 281, respectively while the protein contents were 0.33, 0.31, and 0.25% (w/w), respectively. EPSs from W. confusa SKP 173 and W. cibaria SKP 182 contained glucose only but EPS from L. citreum SKP 281 contained glucose and glucitol. Viscosities of the 2% (w/w) freeze-dried EPS solution were 9.60, 8.00, and 8.20 centipoise (cP) for EPS from SKP 173, 182, and 281, respectively. Viscosities of culture grown in MRS broth with 5% sucrose (no glucose) were 92.98, 57.19, and 18.8 cP, respectively. The average molecular weights of EPSs were larger than 2 × 10⁷ Da. Fourier transform infrared spectroscopy (FT-IR) analyses of EPSs showed typical carbohydrate peaks, suggesting that the EPSs consisted of pyranose saccharides with α-(1,6) and α-(1,3) glycosidic linkages. L. citreim SKP 281 was used as the starter for yogurt fermentation, and EPS production was confirmed.

• Journal of Microbiology and Biotechnology
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• v.16 no.8
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• pp.1240-1247
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• 2006

The present study investigated the influence of the aeration rate and agitation intensity on the production of the mycelial biomass and antioxidative exopolysaccharide (EPS) in Ganoderma resinaceum. In submerged cultures with varying agitation speeds and aeration rates in a stirred-tank reactor, the maximum mycelial biomass and maximum EPS concentration were achieved at 50 rpm and 300 rpm, respectively. Under varying aeration rates, the highest amount of mycelial biomass (18.1 g/l) was accumulated at the lowest aeration rate (0.5 vvm) and the maximum EPS production (3.0 g/l) obtained at 1.0 vvm. A compositional analysis revealed that the five different EPSs were protein-bound heteropolysaccharides, consisting of 87.17-89.22% carbohydrates and 10.78-12.83% proteins. The culture conditions had a striking affect on the carbohydrate composition of the EPS, resulting in different antioxidative activities. All the EPSs showed strong scavenging activities against superoxide and 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radicals, whereas no clear trend in antioxidative activity was observed against hydroxyl radicals and lipid peroxides. Although the precise reason for this difference is still unclear, the high glucose moiety of EPS is probably linked to its broad spectrum of antioxidative activity.

• Journal of Microbiology and Biotechnology
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• v.21 no.11
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• pp.1174-1178
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• 2011

Exopolysaccharides (EPSs) are microbial polysaccharides that are released outside of the bacterial cell wall. There have been few studies on EPS-producing lactic acid bacteria that can enhance macrophage activity and the underlying signaling mechanism for cytokine expression. In the current study, EPS-overproducing Lactobacillus (L.) paracasei KB28 was isolated from kimchi and cultivated in conditioned media containing glucose, sucrose, and lactose. The whole bacterial cells were obtained with their EPS being attached, and the cytokine-inducing activities of these cells were investigated. Gas chromatography analysis showed the presence of glucose, galactose, mannose, xylose, arabinose, and rhamnose in EPS composition. EPS-producing L. paracasei KB28 induced the expression of tumor necrosis factor (TNF)-${\alpha}$, interleukin (IL)-6, and IL-12 in mouse macrophages. This strain also caused the degradation of $I{\kappa}B{\alpha}$ and phosphorylation of the major MAPKs: Jun N-terminal kinase (JNK), p38, and extracellular signal-regulated kinase (ERK)1/2. The use of pharmacological inhibitors showed that different signaling pathways were involved in the induction of TNF-${\alpha}$, IL-6 and IL-12 by L. paracasei KB28. Our results provide information for a better understanding of the molecular mechanisms of the immunomodulatory effect of food-derived EPS-producing lactic acid bacteria.