• KSBB Journal
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• v.19 no.5
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• pp.381-384
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• 2004

The antimicrobial and antioxidative activities were investigated to confirm the utility of wood vinegar. Antimicrobial activity was performed by paper disc method and liquid culture. The growth inhibition was observed in all microbial species at a dose of as low as 25 $\mu$m of wood vinegar by paper disc method. Also, in liquid culture, S. cerevisiae and P. aeruginosa were more inhibited the growth than others in the concentration of $2\%$ (v/v). For measuring of antioxidative activity, wood vinegar was fractionated with acidic, phenolic, basic and neutral fraction; and their antioxidant activities were measured by the radical scavenging effect on DPPH radical. In four fractions, phenolic fraction showed high antioxidative activity.

• Microbiology and Biotechnology Letters
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• v.23 no.4
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• pp.405-410
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• 1995

In order to screen dextranase with high dextranolytic activity from microbial origins, dextranase producing fungal isolates were isolated from soil of the Taeion area. 197 strains with dextranolytic activities were isolated, out of which 3 strains with high dextranolytic activities were selected in the first screening. A strain (GR-98) with a best dextranolytic activity was selected in the second screening. The strain was identified to be similiar Aspergillus ustus by the morphological and cultural characteristics. The optimum culture temperature and initial pH for the dextranase production of the strain was 30$\circ$C and 7.0, respectively. The optimum culture medium was composed of 2% dextran, 0.3% KNO$_{3}$, 0.05% K$_{2}$HPO$_{4}$, 0.02% MgSO$_{4}$-7H$_{2}$O, 0.05% KC1, and 2.5 $\mu$g/ml pyridoxamine, and the enzyme production was maximum when the strain was subcultured at 30$\circ$C for 7 days.

• Microbiology and Biotechnology Letters
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• v.27 no.1
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• pp.35-40
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• 1999

Alternan known as a kind of dextran is a linear and cyclic polysaccharide which is synthesized with sucrose by alternaansucrase (EC2.4.1.140) of Leuconostoc mesenteroides. But this polysaccharide is different from dextran in its structure and other properties. For the purpose of applying alternan for the food, cosmetic, and pharmaceutical industries, we isolated an excellent alternan-porducing strain, Leu. mesenteroides CBI-110. The optimum culture conditions were studied to improve the yield, and the activity of alternansucrase was increased up to 33U/ml in the optimum culture media. The concentrations of $Mn^{2+}$ and $Cu^{2+}$ ions were 0.01% and 0.03%, respectively, for the effective production of alternan. Finally, we obtained 25.6g/L of alternan.

• Korean Journal of Organic Agriculture
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• v.8 no.1
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• pp.79-88
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• 1999

In order top investigate the growth of water dropwort grown by sandculture irrigated with recirculated tilapia aquaculture water, these experiments were carried out. Fish(tilapia) production and biofiltration provided by sand cultured water dropwort(Oenanthe stolonifera DC.) were linked in a closed system of recirculation water. Water dropwort was irrigated with water drawn from the tilapia tank and drainage from sand beds was returned to the fish tank. The temperature, pH and EC of tilapia culture water were stable. The growth of water dropwort grown by sandculture with aquaculture water was normal. Microbial activity of the biofilterbed irrigated by tilapia rearing water was higher than that of biofilterbed irrigated by tapwater. The feasibility of an integrated, recirculatory system for concurrent production of water dropwort and fish with no additional fertilization application was demonstrated.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.6
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• pp.797-802
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• 2001

Two strains of rumen fungi (Piromyces rhizinflata B157, Orpinomyces joyonii SG4) and three strains of rumen cellulolytic bacteria (Ruminococcus albus B199, Ruminococcus flavefaciens FD1 and Fibrobacter succinogenes S85) were used as mono-cultures or combinationally arranged as co- and sequential-cultures to assess the relative contributions and interactions between rumen fungi and cellulolytic bacteria on rice straw degradation. The rates of dry matter degradation of co-cultures were similar to those of corresponding bacterial mono-cultures. Compared to corresponding sequential-cultures, the degradation of rice straw was reduced in all co-cultures (P<0.01). Regardless of the microbial species, the cellulolytic bacteria seemed to inhibit the degradation of rice straw by rumen fungi. The high efficiency of fungal cellulolysis seems to affect bacterial degradation rates.

• Journal of Microbiology and Biotechnology
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• v.23 no.8
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• pp.1140-1146
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• 2013

Bioelectrochemical systems (BESs) have been suggested as a new technology for wastewater treatment while accomplishing energy and chemical generation. This study describes the performance of BESs based on mixed culture that are capable of reducing carbon dioxide to acetate. The cathode potential was a critical factor that affected the performance of the BESs. The rate of acetate production increased as the electrode potential became more negative, from 0.38 mM $d^{-1}$ (-900 mV vs. Ag/AgCl) to 2.35 mM $d^{-1}$ (-1,100 mV), while the electron recovery efficiency of carbon dioxide reduction to acetate increased from 53.6% to 89.5%. The microbial population was dominated by relatives of Acetobacterium woodii when a methanogenic inhibitor was added to the BESs initially.

• Journal of Microbiology and Biotechnology
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• v.1 no.3
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• pp.202-206
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• 1991

To produce acetoin as a precursor of the tetramethylpyrazine flavor compound from citrate by Lactococcus lactis ssp. lactis biovar. diacetilactis FC1, fermentation factors such as inital pH of culture media, temperature, concentration of Na-citrate, thiamin-HC1 and sugars were examined. The best acetoin production was achieved with initial pH in the culture media of 5.5, fermentation temperature of $34^{\circ}C$, Na-citrate concentration of 3%, addition of thiamin-HC1 at 2 mg/l and galactose as a carbon source. When fermentation was carried out under the optimum conditions, the exhaustion of Na-citrate and the production of acetoin took simultaneously and acetoin reached the maximum content, 80 mmole/l after 20 hours.

• Journal of Microbiology and Biotechnology
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• v.1 no.4
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• pp.281-284
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• 1991

To investigate the optimum conditions for the production of ammonia as a precursor of tetramethylpyrazine flavor compound from arginine by Lactococcus lactis ssp. lactis biovar. diacetilactis FC1, fermentation factors such as initial pH of culture media, fermentation temperature, concentration of arginine-HC1, and sugars were examined. The optimum conditions were initial pH 5.5 of the culture media, fermentation temperature of $34^{\circ}C$, 6% (w/v) of arginine-HC1, and 1% (w/v) of galactose as a carbon source. Under the optimum fermentation conditions, 40 mmole/l of ammonia was produced after 40 h.

• International Journal of Advanced Culture Technology
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• v.8 no.3
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• pp.211-215
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• 2020

Currently, most of the chlorine dioxide gas is processed at the beginning of storage or distribution. It has the disadvantage of not being able to continuously process gas since there is no system that can continuously process it during the distribution process. Therefore, in order to minimize changes in freshness and quality during the distribution process of agrifood, there is a need for a sustained-release chlorine dioxide gas treatment technology that can be continuously released. Therefore, in this study, the film to be used was examined so that the chlorine dioxide gas can be continuously released for a certain period of time, the concentration of the reactant and the viscosity at the time of the reaction were determined, and a chlorine dioxide gas gel pack was manufactured using this optimal condition. In addition, the gel pack was used to measure the amount of chlorine dioxide gas released and the sterilization effect of food poisoning bacteria.

• Korean Journal of Microbiology
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• v.30 no.1
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• pp.65-69
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• 1992

It is proposed the polyacrylamide gel, instead of agar, could be used for the solid cultures of microorganisms including Streptomyces strains. Polymerization and gellation of 5% acrylamide solution were done by autoclaving for 5 min at 121.deg.C and no hindered by the addition of nutrient-rich media. In particular, pH buffer solution suitable for corresponding microorganisms must be used in the preparation of culture media. Comparing with agar, it was discussed that polycrylamide gel had many advantages such as gellation within the wide range of strong acid Carbon and Nitrogen sources, requirement tests of growth factors and minerals, sterization at high temperature, diffusion assays of products depending on the pore size of gel, and stability and standarization of microbial cultures.