• Microbiology and Biotechnology Letters
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• v.24 no.3
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• pp.274-281
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• 1996

A bacterium producing Cyclodextrin Glucanotransferase (CGTase) and Cyclodextrinase (CDase) was isolated from soil, and named as Bacillus stearothermophilus KJ16. The growth of the isolated strain occurred in two steps, and syntheses of CGTase and CDase were dependedt on the growth cycle of the cell. CGTase was constitutively synthesized during the 1st growing phase, while CDase was synthesized inducibly during the 2nd growing phase. When the midium pH was controlled at 7.0 the maximum enzyme activities of CGTase and CDase were increased by 12-fold (1300 mU/ml) and 2-fold (225 mU/ml), respectively, compared with the pH-uncontrolled batch culture. The CGTase of the isolate converted soluble starch to CDs with the ratio of $\alpha$-CD:$\beta$-CD:$\gamma$-CD=42:46:12 at $55^{\circ}C$.The optimal pH and temperature of CGTase were 6.0 and $60^{\circ}C$, respectively and the optimal pH and temperature of CDase were 6.0 and $55^{\circ}C$. The molecular weights of the purified CGTase and CDase were estimated to be 65, 000 and 68, 000 dalton, respectively. Among several substrates, $\gamma$-CD was most rapidly hydrolyzed by the purified CDase.

• 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 Microbiology and Biotechnology
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• v.20 no.2
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• pp.410-414
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• 2010

A bacterial strain, 13-$25^T$ with xylanolytic activity isolated from a single soil sample, was characterized with respect to its phenetic and phylogenetic characteristics. The cells of the isolate are Gram-staining variable rods, but spore formation was not observed. This strain is catalase- and oxidase-positive, and able to degrade starch and xylan. The predominant fatty acids are anteiso-$C_{15:0}$, $C_{16:0}$, and iso-$C_{16:0}$. The major respiratory quinone is menaquinone 7(MK-7), with a polar lipid profile consistent with the genus Cohnella. The DNA G+C content is 54.3 mol%. The 168 rRNA gene sequence analysis indicates that this organism belongs to the genus Cohnella, with Cohnella panacarvi as the closest phylogenetic neighbor. Low levels of 168 rRNA gene sequence similarity (<97.0%) with respect to other taxa with published names and the identification of distinctive phenetic features in the isolate indicate that the strain 13-$25^T$ represents a novel species of the genus Cohnella, for which the name Cohnella damensis sp. novo is proposed. The type strain is 13-$25^T$ (=CCTCC AB $208103^T$=KCTC $13422^T$).

• Korean Journal of Agricultural Science
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• v.37 no.3
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• pp.387-392
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• 2010

This studies were carried out to assess fermentation properties of amylase activity and added rice yogurt of Enterococcus faecium KHM-11 isolated from Korean human milk. The amylase activity of Enterococcus faecium KHM-11 was above 23 units. Characterization of carbohydrate fermentation of Enterococcus faecium KHM-11 has D-ribose, D-lactose, L-arabinose and starch. Titratable acidity and viable count of lactic acid bacteria of 4% rice yogurt was higher compared to the 0%. Therefore we were discussed Enterococcus faecium KHM-11 is suitable microorganism for fermented milk added rice powder. Hydrolysates of sugars of fermented milk with 4% rice powder cultured Enterococcus faecium KHM-11 were analyzed by TLC and HPLC. Hydrolysates of lactose and galactose were revealed and hydrolysates of glucose was not revealed in results of TLC and HPLC.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.1
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• pp.51-56
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• 1998

A bacteium, KP-6408, capable of hydrolyzing fibrin was isolated from Chungkook-jang, which was possibly identified as a strain of Bacillus sp. The effects of culture condition and medium composition on the enzyme production were investigated. Among nitrogen sources tested, yeast extract was the most effective for the enzyme production, and the level of the concentration for the optimal enzyme production was 0.2%(w/v). For carbon sources, glucose was the best for the enzyme production with the level of 2.0%(w/v). The enzyme was maximally produced by cultivating the enzyme production with the level of 2.0%(w/v). The enzyme was maximally produced by cultivating the organism at the liquid medium of the initial pH 8.0 and temperature of 4$0^{\circ}C$. In Chungkook-jang fermentation, the enzyme was maximally produced when incubated at 35$^{\circ}C$ for 24 hrs using soybean as a solid medium. The addition of various rice starch to the soybean in Chungkook-jang fermentation lowered the enzyme production.

• YAKHAK HOEJI
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• v.37 no.4
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• pp.389-396
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• 1993

An Actinomycetes strain JB isolated from Mt. Hanla had a strong antimicrobial activity against gram positive bacteria and tumor cell growth inhibition. Especially, it couldn't degrade starch and casein as organic compounds. It was resist on lincomycin and rifampicin. The spore mass of strain JB which was arethrospore was white. DAP of the cell wall was L, L-DAP. Antimicrobial material was heat stable, dissolved in ethyl acetate, and not dissolved in butanol. In the pressnce of 0.1% phenol and 4% sodium chloride, strain JB could grow, but it didn't growth at below $10^{\circ}C$. Strain JB didn't use dextran, sodium acetate and sodium citrate as sole carbon source and L-cystein and L-thereonine as nitrogen source. The filtered broth of strain JB had the antimicrobial activity against gram positive bacteria, especially Staphylococcus aureus (ATCC 65389) and the growth inhibition of tumor cell line.

• Korean Journal of Food Science and Technology
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• v.54 no.4
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• pp.377-385
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• 2022

This study examined the dietary fiber content of potato and physicochemical characteristics of potato starch isolated from various cultivars. The total dietary fiber content of the Arirang1ho cultivar was 6.30%, which was higher than that of other cultivars. The amylose content ranged from 36.76-55.75%, with Sooseon having the highest amylose content. Analysis of the degree of amylopectin polymerization revealed that all cultivars had a high proportion of DP (degree of polymerization) 13-24. The phosphate content ranged from 45.90-84.23 mg/100 g, with Arirang1ho having the highest and Eunseon having the lowest phosphate content. The resistant starch content ranged from 58.94-79.87%. Geumseon showed the highest breakdown in the range of 587.45-1,129.72 RVU (rapid viscosity unit). Sooseon had the lowest gelatinization enthalpy value for potato starch in the range of 5.54-7.64 J/g. These results provide basic data for the use of potatoes in industrial applications.

• 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.

• Microbiology and Biotechnology Letters
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• v.17 no.2
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• pp.142-147
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• 1989

Six plasmids of B. thuringiensis serovar. kurstaki HD73 were detected, with approximate sizes of 7.4, 7.8, 8.1, 11.3, and 75 Kb, as well as a low copied plasmid of similar length to 75 Kb. Partially cured mutants from B. thuringiensis HD73 were obtained either by the treatment of the curing agent, ethidium bromide(0.02 $\mu\textrm{g}$/$m\ell$) or by spontaneous curing, Acrystalliferous mutants(Cry$^-$) were identified by microscopic observation and immunoblotting with polyclonal antibody against 133 KD deltaendotoxin of HD73. Ten Cry$^-$ mutants were found to be lack of 75 Kb plasmid. These results implicated that this plasmid was associated with delta-endotoxin production, After isolating the mutants, we streaked them on potato dextrose agar, spizizen casamino acid glucose, starch agar, and nutrient agar. Only on starch agar medium did morphologies of Cry$^-$ appear translucent and light greyish. On the other hand, the mutants of B. thuringiensis isolated from Korean soil, designated KBS722, were obtained by the treatment of novobiocin (3 $\mu\textrm{g}$/$m\ell$). Acrystalliferous mutants of KBS722 were less translucent than HD73 mutants' only on nutrient agar medium. Compared the plasmid profile of the mutants with delta-endotoxin production, the results seemed to indicate that the insecticidal protein gene of B. thuringiensis isolates KBS722 located on about 225 Kb plasmid DNA.

• Journal of Animal Science and Technology
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• v.48 no.3
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• pp.415-424
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• 2006

The purpose of this study was to investigate the fungal growth and enzyme production under different carbohydrate substrate conditions. The anaerobic fungus Neocallimastix sp. NLRI-3 isolated from the rumen of Korean native goat was incubated with different carbohydrate media containing 0.2% of glucose, starch, rice straw, filter paper, carboxymethyl cellulose(CMC), Sigmacell cellulose, xylan or xylose, respectively. The culture head gas production was the highest in the culture of filter paper medium, and the lowest in the culture of CMC medium at 96h incubation (P<0.05). The fungal zoospore production reached peak at 72h incubation, and its number was the highest in rice straw medium among the treatments (P<0.05). At 96h incubation, carboxymethyl cellulase(CMCase) activity was the highest in the culture of filter paper medium and the lowest in the culture of starch medium (P<0.05). While xylanase activity was the highest in the culture of rice straw medium and the lowest in the culture of xylose medium(P<0.05) at 72h incubation. There were no differences in culture supernatant protein expression among the treatments. However, the patterns of enzyme expression were different among the treatments with zymogram analysis. Six CMCases and 4 xylanase were detected from the results of zymogram analysis. Therefore the present study indicating that the fungal enzyme expression could be stimulated with insoluble substrates in the culture medium.