• Korean Journal of Veterinary Research
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• v.27 no.2
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• pp.191-200
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• 1987

Attempts were to produce porcine leukocyte interferon(PorLeIF) and porcine immune interferon (PorIIF) in the culture of porcine leukocytes. The interferons produced were tested for antiviral activity against vesicular stomatitis virus on poreine-derived PK(15) cells, human-derived FL cells, and Korean native black goat-derived BGK cells. The results were summarized as follws: 1. In the isolation of porcine leukocytes, the mean isolation rate by the buffy coat separation method (28.7%) was higher than that by the hydroxyethyl starch-RBC sedimentation method (9.2%). 2. When NDV(BI)-induced PorLeIFs were assyed on PK(15) cells and FL cells, the mean titers were 129 IU/ml and 72 IU/ml respectively, being 55.8% of the activity in homologous species system expressed in heterologous system. 3. The activities of PHA P-induced PorIIFs were 197 IU/ml on PK (15) cells and no activity on human FL cells. The mean antiviral activity of PorIIF was 1.5 times that of PorLeIF in PK (15) cells. 4. The cytopathic effect of vesicular stomatitis virus was observed in BGK cells derived from Korean native black goat kidney permitting interferon assay on the cells. While the cross-species antiviral activity of reference human ${\alpha},\;{\beta}-interferon$ was observed on the cells, PorLeIF and PorIIF did not show any activity.

• Biotechnology and Bioprocess Engineering:BBE
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• v.9 no.4
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• pp.303-308
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• 2004

We isolated a novel lactic acid bacterium from a Korean traditional fermented food, soybean paste. The newly isolated strain, dubbed RKY2, grew well on glucose, sucrose, galactose, and fructose, but it could not utilize xylose, starch, or glycerol. When the partially amplified 16S rDNA sequence (772 bp) of the strain RKY2 was compared with 10 reference strains, it was found to be most similar to Lactobacillus pentosus JCM $1588^T$, with 99.74% similarity. There-fore, the strain RKY2 was renamed Lactobacillus sp. RKY2, which has been deposited in the Korean Collection for Type Cultures as KCTC 10353BP. Lactobacillus sp. RKY2 was found to be a homofermentative lactic acid bacterium, because its end-product from glucose metabolism was found to be mainly lactic acid. It could produce more than 90 g/L of lactic acid from MRS medium supplemented with 100 g/L of glucose, with 5.2 g $L^-1$ $h^-1$ of productivity and 0.95 g/g of lactic acid yield.

• Journal of Life Science
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• v.8 no.4
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• pp.387-394
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• 1998

A thermophilic bacterium (strain DG0303) producing a thermostable $\alpha$-glucosidase was isolated from manure and identified as Bacillus sp. Strain DG0303 produced high level of $\alpha$-glucosidase compared with other thermophilic Bacillus strains. The cellular protein patterns were also compared with other Bacillus strains by sodium dodecyl sulfatepolyacrylamide gel electrophoresis(SDS-PAGE). On the basis of 16S rDNA analysis the Bacillus sp. DG0303 was found to be a member of Bacillus rDNA group 5. The optimum temperature for growth was 65$\circ$C and no growth was obtained at 40$\circ$C or 75$\circ$C. The optimum pH for growth was 5.5 to 8.5. $\alpha$-glucosidase activity was produced during growth and most activity was detected in the culture supernatant. The $\alpha$-glucosidase production was constitutive in the absence of carbohydrates. High level of enzyme activity was detected when the culture was grown on medium containing starch. Addition of glucose resulted in the repression of the $\alpha$-glucosidase production. The optimum pH and tempoerature for enzyme activity were pH 5.0 and 65$\circ$C, respectively. When analyzed by zymogram, the culture supernatant showed a single $\alpha$-glucosidase band with a molecular weight of approximately 60,000.

• Food Engineering Progress
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• v.23 no.3
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• pp.193-199
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• 2019

This study aimed to investigate the impact of protease treatments on the yield of rice starch (RST) from frozen rice flours, and to compare the physicochemical properties of RST by alkaline steeping (control) and enzymatic isolation (E-RST) methods. Although the yield of E-RST, prepared according to conditions designed by the modified 23 complete factorial design, was lower than the control, the opposite trends were observed in its purity. E-RST (RST1, isolated for 8 h at 15℃ with 0.5% protease; RST2, isolated for 24 h at 15℃ with 1.5% protease; RST3, isolated for 24 h at 15℃ with 0.5% protease) with the yields above 50% were selected. Amylose contents did not significantly differ for the control and RST2. Relative to the control, solubilities were higher for all E-RST, but swelling power did not significantly differ for E-RST except for RST1. Although all E-RST revealed higher gelatinization temperatures than the control, the reversed trends were found in the gelatinization enthalpy. The pasting viscosities of all E-RST were lower than those of the control. Consequently, the enzymatic isolation method using protease would be a more time-saving and eco-friendly way of preparing RST than the alkaline steeping method, even though its characteristics are different.

• Microbiology and Biotechnology Letters
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• v.10 no.1
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• pp.15-26
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• 1982

A potential fungal lipid producer from starch, which was identified as Muror plumbeus, was isolated from natural sources and its optimum cultivation condition for lipid production was investigated. The Mucor plumbeus FRI 0007 showed the highest felt weight and lipid content which were 2.09 $\pm$ 0.24g per 50$m\ell$ of medium and 37.43% on dry weight basis respectively after 20 days incubation on the medium containing 21% of starch as a carbon source. The urea was the best nitrogen source as compared with sodium nitrate, potassium nitrate, magnesium nitrate, ammonium nitrate and ammonium acetate and its optimum concentration was 2.14g/$\ell$, showing 2.39 $\pm$ 0.07 g felt/50$m\ell$ of medium and 50.73% lipid content on dry weight basis after 25 days incubation. Besides the starch as a carbon source and urea as a nitrogen source, the Mucor plumbeus FRI 0007 utilized ZnSO$_4$, MgSO$_4$, NaH$_2$PO$_4$, $K_2$SO$_4$and FeCl$_3$as mineral sources. However, it did not require ail the above 5 minerals in group in-dispensably for its growth and lipid accumulation. The lipid and economic coefficient of Mucor plumbeus FRI 0007 grown on the medium containing 0.44g $K_2$SO$_4$or 5.00g MgSO$_4$/$\ell$solely were 14.96 and 15.37 and 31.12 and 26.10 which was higher than those on the medium containing the above 5 minerals.

• Mycobiology
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• v.40 no.2
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• pp.94-99
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• 2012

During an investigation of fungi from an elm tree infested with bark beetles in Korea, one isolate, DUCC401, was isolated from elm wood. Based on morphological characteristics and phylogenetic analysis of the internal transcribed spacer and 28S rDNA (large subunit) sequences, the isolate, DUCC401, was identified as Mariannaea samuelsii. Mycelia of the fungus grew faster on malt extract agar than on potato dextrose agar and oatmeal agar media. Temperature and pH for optimal growth of fungal mycelia were 25oC and pH 7.0, respectively. The fungus demonstrated the capacity to degrade cellobiose, starch, and xylan. This is the first report on isolation of Mariannaea samuelsii in Korea.

• Microbiology and Biotechnology Letters
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• v.18 no.5
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• pp.443-448
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• 1990

The objective intended for this study is that of providing a fairly practical guide to the use of natural pigment in the food industry. Streptomyces isolated from soil were carried out test for the excretion of their bluish purple pigment. One strain of Streptomyces, strain KS-89 showed a high production of bluish purple pigment on the glycerol starch-glutamate medium. The morphological and physiological characteristics of the strain KS-89 were studied according to the methods of Bergey's manual, Nonomura's classification, and Ridham and Lyons classification. Based on the results obtained in these experiments, strain KS-89 was identified as Streptomyces californicus.

• Journal of Aquaculture
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• v.19 no.1
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• pp.40-46
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• 2006

Bacillus subtilis strain with highly active chitosanase was isolated from the intestine of Sebastiscus marmoratus (scorpion fish). It was named as Bacillus subtilis CH1 by morphological, biochemical and 165 rRNA gene analysis. The optimal conditions for chitosanase production were investigated. The optimum carbon and nitrogen sources for Bacillus stibtilis CH1 were 2% starch and 1% yeast extract respectively. Unlike other chitosanases, the expression of this chitosanase was not induced or slightly induced with chitosan. The chitosanase secreted into the medium were concentrated with ammonium sulfate precipitation and purified by gel permeation chromatography. The molecular weight of purified chitosanase was 30 kDa. The optimum pH and temperature of purified chitosanase were 5.5 and $60^{\circ}C$ respectively. The purified chitosanase was continuously thermostable at $40^{\circ}C$ and showed stable activity between pH 6.0 and 8.0. Chitosanase activity of Bacillus subtilis CH1 under optimum condition was 4.1 units/ml.

• Microbiology and Biotechnology Letters
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• v.20 no.1
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• pp.34-39
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• 1992

For the screening of new-functional and specific exopolysaccharide, a bacterium strain was isolated from soil through the two steps of screening. The isolated bacterium was identified as Bacillus polymyxa KS-1 according to the criteria of morphological, physiological, and chemical taxonomic analyses. The exopolysaccharide was composed of glucose:galactose: mannose and galactosamine in an approximate molar ratio of 1.00:0.36:1.02:1.10. The produced exopolysaccharide by Bacillus polymyxa KS-1 was found to be revealed new acidic polysaccharide which did not contain pentose, ketose, starch, and uronic acid.

• Microbiology and Biotechnology Letters
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• v.27 no.6
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• pp.509-514
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• 1999

Forty seven amylolytic Bifidobacterium strains were isolated on starch-containing agar medium from the faecal samples of the various age groups of Korean. From these amyloytic Bifidobacterium spp., two strains of KFRI 1535, identified temporarily as Bifidobacterium longum, and KFRI 1550, identified as Bifidobacterium breve, showed great macrophage-stimulating activity for the production of tumor necrosis factor-$\alpha$ and inteleukin-6. As the cell concentration increased the cytokine production increased, although in some strains the cytokine levels started to decline over cell concentration increased the cytokine production increased, although in some strains the cytokine levels started to decline over cell concentration of $250\mu\textrm{g}$/ml. the strains which showed high cytokine-stimulating activity generally showed greater production of nitric oxide even though differences were less between strains. Selected Bifidobacterium strains were compared for their fermentation capability in saccharified rice solution and in apple pomace mixture.