• Microbiology and Biotechnology Letters
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• v.23 no.4
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• pp.439-445
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• 1995

Identification of Actinomycetes isolate strain SH-8002, a producer of ACE inhibitor, based on procedures employed in the international Streptomyces project. The strain, designated as SH-8002, was identified as Streptomyces zoamyceticus SH-8002 based on its morphological, physiological, biochemical and chemotaxonomic characteristics. The ACE inhibitor produced by the strain was highly achieved in fermentation medium condition that was 1% soluble starch, 0.5% tryptone, 0.2% K$_{2}$HPO$_{4}$, 0.2% CaCO$_{3}$, 0.1% NaCl, pH 8.0 at 30$\circ$C for 144 hrs.

• Journal of the East Asian Society of Dietary Life
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• v.14 no.5
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• pp.508-512
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• 2004

In other to produce vinegar using Schizandra chinensis Ballon(omija), acetic acid bacteria(AAB) were selected from several conventional vinegars, and total 30 acetic acid bacterial strains were isolated. Among the isolated strains, a strain was selected from medium containing omija juice which showed the highest productivity of acetic acid. The strain was identified as Acetobacter sp. C5-1b. Optimum conditions for acetic acid production of Acetabacter sp. C5-1b were involved with 30t: of fermentation temperature and shaking culture. The acidity of culture medium was reached to 5.3% after 8 days shaking cultivation at 30℃.

• Proceedings of the Microbiological Society of Korea Conference
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• 2009.05a
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• pp.78-78
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• 2009

$^1H$ NMR spectroscopy coupled with multivariate statistical analysis was used for the first time to investigate metabolic changes in musts during alcoholic fermentation and wines during ageing. Three Saccharomyces cerevisiae yeast strains (RC-212, KIV-1116 and KUBY-501) were also evaluated for their impacts on the metabolic changes in must and wine. Pattern recognition (PR) methods, including PCA, PLS-DA and OPLS-DA scores plots, showed clear differences for metabolites among musts or wines for each fermentation stage up to 6 months. Metabolites responsible for the differentiation were identified to valine, 2,3-butanediol (2,3-BD), pyruvate, succinate, proline, citrate, glycerol, malate, tartarate, glucose, N-methylnicotinic acid (NMNA), and polyphenol compounds. PCA scores plots showed continuous movements away from days 1 to 8 in all musts for all yeast strains, indicating continuous and active fermentation. During alcoholic fermentation, highest levels of 2,3-BD, succinate and glycerol were found in musts with the KIV-1116 strain, which showed the fastest fermentation or highest fermentative activity of the 3 strains, whereas the KUBY-501 strain showed the slowest fermentative activity. This study highlights the applicability of NMR-based metabolomics for monitoring wine fermentation and evaluating the fermentative characteristics of yeast strains.

• Korean Journal of Microbiology
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• v.37 no.4
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• pp.299-304
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• 2001

Teicoplanin is a kind of glycopeptide antibiotics produced by Actinoplanes teichomyceticus, and used in the clinical antibiotic such as vancomycin against methicillin-resistant Stabphylococcus aureus (MRSA). Actino planes teichomyceticus ATCC 31121 was mutated with UV to obtain a superior mutant strain with increased level of teicoplanin production. In this investigation, lethal curve was obtained and the optimal condition to induce mutagenesis was determined to isolate the desirable mutant strain. It was also confirmed that teicoplanin activities by agar diffusion method was compared with the parent strain. One mutant strain, T991014-1 with the highest productivity, was finally selected, and was characterized through the various tests such as amylase activity, protease activity, halotolerance, antibiotic resistance, autotoxicity, and productivity. Ad fermentation characteristics of the mutant strain were also studied.

• Journal of Microbiology and Biotechnology
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• v.5 no.5
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• pp.297-301
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• 1995

An anthracycline antibiotic, aclacinomycin A (aclarubicin), was produced from a mutant strain of Streptomyces lavendofoliae. The mutant strain which showed a 4-fold higher productivity of aclacinomycin A compared with the parent strain was also found to produce a significantly higher amount of aclacinomycin A than the reported production strain, Streptomyces galilaeus. The aclacinomycin A was produced up to 125 mg/l using potato starch and soybean meal as carbon and nitrogen sources, respectively, on a 3 liter scale fermentation in a 5 liter jar fermentor. The mutant strain also produced significant amount of aclacinomycins Band Y. Aclacinomycin A was isolated from the culture broth by solvent extractions and further purified by silica gel column chromatography. The yield of aclacinomycin A with over 99$%$ purity was found to be over 60$%$ starting from 3 liters of culture broth.

• Journal of Microbiology and Biotechnology
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• v.2 no.4
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• pp.288-292
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• 1992

Kinetics of anaerobic ethanol fermentation by Clostridium thermohydrosulfuricum were investigated for the one-step production of ethanol from starch. A mutant strain with a high ethanol yield was induced from C. thermohydrosulfuricum. The mutant, designated as ME4, produced anaerobically 6.1 g/l of ethanol, 3.1 g/l of lactate and 0.1 g/l of acetate from 20 g/l of starch at $68^{\circ}C.

• Korean Journal of Food Science and Technology
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• v.30 no.4
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• pp.924-933
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• 1998

Kochujang, fermented hot pepper-soybean paste, was prepared by two common varieties of red pepper and natural fermented (NF) or pure cultured (PC) meju (soybean mass that is soaked, steamed, mashed and fermented by natural microflora or pure strain) and monitored their taste related component, enzyme activity and microflora during fermentation at $25^{\circ}C$ for 120 days for confirming possibility of kochujang fermentation control. The reducing sugars, amino type nitrogen (reference quality factor) and amino acid content in PC kochujang were 11.4%, 0.58% and 1,372.9 mg% respectively, 7.1%, 0.42% and 1,038.7 mg% in NF kochujang. It is concerned higher ${\alpha}-{\;}and{\;}{\beta}-{\;}amylase$ and, acid and neutral protease in PC kochujang during fermentation. The meju fermented by selected pure strain (A. oryzae CBU) can be applied to produced better quality of kochujang instead of natural meju.

• Journal of Microbiology and Biotechnology
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• v.29 no.4
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• pp.617-624
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• 2019

Bacterial nanocellulose (BNC) which is generally synthesized by several species of bacteria has a wide variety of industrial uses, particularly in the food and material industries. However, the low levels of BNC production during the fermentation process should be overcome to reduce its production cost. Therefore, in this study, we screened and identified a new cellulose-producing bacterium, optimized production of the cellulose, and investigated the morphological properties of the cellulosic materials. Out of 147 bacterial isolates from ripened fruits and traditional vinegars, strain SFCB22-18 showed the highest capacity for BNC production and was identified as Komagataeibacter sp. based on 16S rRNA sequence analysis. During 6-week fermentation of the strain using an optimized medium containing 3.0% glucose, 2.5% yeast extract, 0.24% acetic acid, 0.27% $Na_2HPO_4$, and 0.5% ethanol at $30^{\circ}C$, about 5 g/l of cellulosic material was produced. Both imaging and IR analysis proved that the produced cellulose would be nanoscale bacterial cellulose.

• Journal of Life Science
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• v.25 no.11
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• pp.1290-1297
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• 2015

Studies of the inactivation of a gene encoding pyruvate decarboxylase, pdc, in an ethanol-producing bacterium, Zymomonas mobilis, identified a mutant strain with 50% reduced PDC activity. To evaluate the possibility of a carbon-flux shift from an ethanol pathway toward higher value fermentation products, including pyruvate, succinate, and lactate, fermentation studies were carried out. Despite attempts to silence pdc expression in the wild-type strain ZM4 using cat-inserted pdc and pdc-deleted homologs by electroporation, the strain isolated showed partial gene activation. Fermentation experiments with the PDC mutant strain showed that the reduced expression level of PDC activity resulted in decreased rates of substrate uptake and ethanol production, together with increased pyruvate accumulation of 2.5 g l^-1 , although lactate and succinate concentrations were not significantly enhanced in these modified strains. Despite numerous attempts, no strains were isolated in which complete pdc inactivation occurred. This result indicates that the ethanol fermentation pathway of this bacterium is totally dependent on the activity of the PDC enzyme. To ensure a redox balance of intracellular NAD and NADH levels, other enzymes, such as lactate dehydrogenase for lactate, and enzymes involved in the production of succinic acid, such as pyruvate dehydrogenase (PDH) and malic enzymes, may be needed for their increased end-product production.

• Korean Journal of Agricultural Science
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• v.4 no.2
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• pp.173-177
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• 1977

These experiments were conducted to investigate the formation of organic acid and ethanol during fermentation by three yeast strains. One of these was industrial strain (No.7) from Japan, and the others were wild types (No. 47, No. 239) isolated from Takju-mash and Strawbery, respectively. Conditions of fermentation were varied by differing the supply of oxygen (air), and by using different fermentation media The results obtained were as follows: 1) All the yeast strains produced higher amount of total organic acid and ethanol under the conditions which were aerobic, i.e. the flasks were opened during fermentation, than in case of using the flasks with fermentation bung. 2) Organic acid and ethanol were produced rapidly in the mash medium than in the semi-synthetic medium, i.e. total amount of organic acid and ethanol was maximized in a short time in the mash medium. 3) On the mash medium, the highest amount of organic acid was obtained by the strain No. 239, the next by No. 7 and the lowest by No. 47. Ethanol was produced on this medium with decreacing order of No. 47, No. 239, and No. 7. 4) The strain No. 239 was proved to be a powerful organic acid producer, yielding higher amount of organic acid especially under the aerobic conditions. 5) Above results suggests that the strain No. 239 could be of useful in alcoholic drink industry, due to its powerful ethanol-producing characteristic accompaning with high yielding of organic acids.