• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.247-250
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• 2000

Extracellular polysaccharide was produced by Pseudomonas elodea ATCC 31461 under aerobic condition. Nitrogen sources in medium affected cell growth and production of exopolymer. Ammonium nitrate limitation was found to be essential for higher production of exopolymer. Conversion rate of exopolymer from glucose under ammonium nitrate limitation was about 5 times higher than with ammonium nitrate.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.334-337
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• 2000

Extracellular polysaccharide was produced by Pseudomonas elodea NK-2000 under nitrogen limitation and aerobic condition, The effect of agiatation speed on cell growth and production of exopolymer was investigated. The agitation speed of 7.5 L fermentor ranged from 200 to 500 rpm. Production of exopolymer increased with higher agitation speed. Maximal cell growth and production of exopolymer from 2% glucose were 3.35 g/l and 3.80 g/l, respectively when agitation speed was 400 rpm.

• Journal of Microbiology and Biotechnology
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• v.14 no.1
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• pp.15-21
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• 2004

The immunomodulating activities and chemical characteristics of a water-soluble exopolymer from submerged mycelial culture of Phellinus pini were studied. Anticomplementary activity of this polymer was found to be $73.2\%$, and its activation system occurred through both classical and alternative pathways, where the classical pathway was detected to be the major one by crossed immunoelectrophoresis. Nitric oxide (NO) release ability and acid phosphatase activity of macrophage were increased by 1.6-fold ($100{\mu}g/ml$) and 3.4-fold ($500{\mu}g/ml$), respectively, and splenocyte proliferation in mixed lymphocyte reaction (MLR) was also increased by 2.6-fold ($200{\mu}g/ml$), compared to the control. The molecular weight of this polymer, determined by HPLC, was under 5 kDa. Total sugar and protein contents were 89.7 and 10.3%, respectively. Both sugar and amino acid compositions of the exopolymer were also analyzed.

• Journal of Korean Society of Environmental Engineers
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• v.36 no.7
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• pp.492-497
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• 2014

This study investigated removal characteristics of organic matters in pretreatment and reverse osmosis (RO) membrane processes for seawater desalination. Also, the influence of the changes in characteristics of organic matters on the membrane fouling was assessed. The pretreatment processes included dual media filtration (DMF), pressurized membrane filtration (MF), and submerged membrane filtration (SMF). Turbidity, UV absorption at 254 nm, dissolved organic carbon, size exclusion chromatography (SEC), fluorescence excitation emission matrix (FEEM), and transparent exopolymer particles (TEP) in raw and processed waters were analyzed. Ions and minerals were not removed by any pretreatment process tested, but were removed over 99% through the RO membrane process. Hydrophobic organics, which can play major role in organic membrane fouling, were relatively readily removed compared with hydrophilic ones. Membrane based pretreatment such as MF and SMF exhibited better removals of organics than conventional DMF. As the levels of organics in pretreated water decreased, the silt density index (SDI) decreased. MF treated water exhibited the lowest SDI value; this is possibly due to the lowest TEP ($0.1-0.4{\mu}m$) concentrations.

• Proceedings of the Korean Society of Life Science Conference
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• 2000.09a
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• pp.30-30
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• 2000

• Journal of Microbiology and Biotechnology
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• v.16 no.12
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• pp.1954-1960
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• 2006

The effects of the exopolymers of Aureobasidium pullulans SM-2001 containing $\beta$-1,3/1,6-glucan on formalin-induced chronic inflammation were observed. Doses of 62.5, 125, and 250 mg/kg of the exopolymers were orally administered once a day for 10 days to formalin-induced chronic inflammatory mice (0.02 ml of 3.75% formalin was subaponeurotically injected into the left hind paw), and then the bilateral hind-paw thickness and volume were measured daily, while the paw wet-weight, histological profiles, and histomorphometrical analyses were conducted at termination. The results were compared with those for diclofenac, indomethacin, and dexamethasone (intraperitoneally injected) 15 mg/kg-dosed groups. All the animals were sacrificed 10 days after dosing. As a result of the formalin injection, a marked increase in the difference between the intact and formalin-induced paw thickness and volume was detected in the formalin-injected control compared with that in the intact control with time, plus at the time of sacrifice, the difference in the paw wet-weights was also dramatically increased. In a histological and histomorphometrical analysis, severe histological profiles of chronic inflammation were detected in the formalin-injected control with a marked increase in the thickness of the skin of the dorsum pedis. However, these formalin-induced chronic inflammatory changes were significantly and dose-dependently decreased by the exopolymer treatment. In conclusion, the exopolymer treatment inhibited the chronic inflammatory response induced by formalin injection in the mice. However, somewhat low efficacies were detected compared with those for the diclofenac-, indomethacin-, and dexamethasone-treated groups.

• KSBB Journal
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• v.17 no.4
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• pp.376-380
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• 2002

Production of the exopolymer by Aureobasidium pullulans SM-2001, UV induced mutant of A. pullulans ATCC 42023, was investigated. The exopolymer produced by A. pullulans SM-2001 was confirmed to be ${\beta}$-1,3-linked homoglucans containing a few ${\beta}$-1,6-linked single glucosyl branches(${\beta}$-1,3/1,6-glucan) with the nuclear magnetic resonance(NMR) spectrum. The average molecular weight of ${\beta}$-1,3/1,6-glucan produced by A. pullulans SM-2001 was about 2.6 ${\times}$ 10$\^$5/ by the gel permeation chromatographic analysis. Sucrose was known to be better carbon source for the production of ${\beta}$ -1,3/1,6-glucan than other tested carbon sources in this study. Maximal conversion rate of ${\beta}$-1,3/1,6-glucan was about 50% when the carbon source was 0.5%(w/v) sucrose.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.17 no.2
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• pp.33-44
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• 2012

Transparent exopolymer particles (TEP) are formed by aggregation of polysaccharide products excreted by phytoplankton and have sticky character like gel. They play important role in the production of marine snow in water column. To study the distribution pattern of TEP concentration and its role in carbon cycle in the surface ocean, we measured pH, Total alkalinity (TA), and chlorophyll-a in addition to physical characteristics of seawater within the surface water column. TEP concentrations ranged from nearly undetectable values to $338{\mu}g\;Xeq\;l^{-1}$. They were considerably lower than previously reported values from costal sites, but showed similar values observed in other oceanic region during phytoplankton bloom periods. The spatial distribution of TEP concentrations were similar to those of chlorophyll-a, which indicate that the production of TEP were closely related to phytoplankton. Calculated total dissolved inorganic carbon ($TCO_2$) from the pH and TA was normalized to 35 psu of salinity ($NTCO_2$) and showed negative linear relationship with temperature. Biological drawdown of $NTCO_2$ ($NTCO_{2bio}$) was estimated from the difference between theoretical $NTCO_2$ values and observed $NTCO_2$. In the warm region located south of $40^{\circ}N$ along the $132.5^{\circ}N$ meridional lines, $NTCO_{2bio}$ showed negative value and TEP concentrations were high. This suggested that negative $NTCO_{2bio}$ may be attributed to the biological processes. At the stations located between 44 and $46^{\circ}N$, TEP concentrations showed high concentration at the chlorophyll-a maximum layer within the water column while they showed low concentration in the surface layer. Carbon content of TEP constituted about 40% of $NTCO_{2bio}$ at the chlorophylla maximum layer. In this study, we could not observe any positive and negative relationship between TEP concentration and $NTCO_2$ or pH. It is obvious that we should consider the importance of TEP in the biological carbon cycling processes within surface layer.

• Proceedings of the Korean Society of Life Science Conference
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• 2001.02a
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• pp.58-58
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• 2001

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.342-345
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• 2000

Effect of volcanic ash on cell growth of Aspergillus sp. and production of exopolymers by Agrobacterium sp. and Aureobasidium pullualns was investigated. The volcanic ash contained various mineral salts such as $SiO_2$, $Al_2O_3$, CaO, $K_2O$. Maximal cell growth of Aspergillus sp. was obtained when 0.3% volcanic ash was added to medium. Cell growth of Aspergillus sp. increased with higher concentration of volcanic ash in medium. Amount of cell growth with 0.3 % volcanic ash was 6.7 times higher than that without volcanic ash. Volcanic ash also stimulated production of exopolymer as well as cell growth. Production of curdlan with 0.1% volcanic ash was 12.40 g/l whereas that without volcanic ash was 9.15 g/l. Production of pullulan with volcanic ash was also higher than that without volcanic ash.