• Journal of Korean Society of Environmental Engineers
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• v.31 no.12
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• pp.1075-1080
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• 2009

The partial lipid degradation with the saturation of double-bond at the acidogenesis stage is known to help subsequent methanogenesis during anaerobic digestion. Acidogenic reactions in an anaerobic sequencing batch reactor (ASBR) and a continuously stirred tank reactor (CSTR) were carried out to compare their performances. A mixture of two unsaturated (oleate and linoleate) and two saturated (palmitate and stearate) long-chain fatty acids (LCFAs) was used as a model substrate. Biomass retention in the ASBR contributed to the enhanced performance at hydraulic retention time (HRT) below 15 hr. Biomass retention in the ASBR contributed to the enhanced performance compared to CSTR even at shorter HRT. ASBR would be a proper reactor configuration for the acidogenesis of lipid-containing wastewater.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.275-278
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• 2000

Bacillus polyfermenticus SCD which is commonly called as 'Bispan strain' has been appropriately used for the treatment of long-term intestinal disorders, since the live strains in the form of active endospores can successfully reach the target intestine. The goal of this study were to get the novel bispan mutant strain and to get higher spore number of bispan mutant in submerged fermentation. Bispan mutant KD21 was obtained using NTG mutagenesis of bispan strain, and bispan mutant was cultivated in 5 L jar fermenter. In this study, productivity and sporulation rate of the bispan mutant KD2l showed approximately 77% increase when compared with bispan strain.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.239-242
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• 2000

Experimental studies on the effects of impeller to provide the microbial transglutaminase derived from Streptoverticillium mobaraense have been conducted. The optimal production medium was determined by latin-square design, and the effects of aeration and agitation were observed by using different sizes and shapes of impellers for the poduction of transglutaminase. The effects of pH and temperature were also evaluated for the production of transglutaminase in flasks. As a result, pH is more effective than temperature for both enzyme production and growth of the microorganism. The peak enzyme activity for transglutaminase in fermenter was 0.7 U/mL, but this was still well below the avereage enzyme activity, 1,3 U/mL, obtained in flask runs.

• Microbiology and Biotechnology Letters
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• v.24 no.6
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• pp.756-762
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• 1996

In order to develop the method for mass production of natural food colorant from Monascus anka, optimum cultivation conditions for producing red and yellow pigments by cultiva- ting the mold in a jar fermenter and their color characteristics were investigated. The mold produced red and yellow pigments both intracellularly and extracellularly. These pigments showed unique light absorption characteristics with maximum absorption of 494, 380, 506, and 388 nm for extracellular red pigment (ERP), extracellular yellow pigment (EYP), intracellular red pigment (IRP), and intracellular yellow pigment (IYP), respectively. Optimum conditions for producing red pigments were found to be temperature 30$\circ$C, initial pH 6.0, rice powder 3-5%, peptone 0.05%, magnesium sulfate 0.25%, aeration rate 0.1 vvm. Optimum temperature for producing yellow pigments was around 35$\circ$C which is higher than that of producing red pigments. The initial pH and rice powder concentration for producing yellow pigments were the same as those of producing red pigments. The higher concentration of nitrogen source and inorganic salt, aeration rate, the more the yellow pigments were produced. The optimum agitation speed was 100 - 300 rpm for pigment production.

• Journal of Animal Environmental Science
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• v.2 no.2
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• pp.123-133
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• 1996

Recently, a greater interest has been placed on the methods of acration control for management of maloders during composting. This study was performed to evaluate the influence of the intermittent aeration method on the composting temperature and chemical components. Combinatoins of cattle manure and rice hulls were placed on a batch composter(3,150-L size) practically designed. The chemical properties of the produced compost were suitable for plant growth, when composting temperature was maintained in the range from 45 to $66^{\circ}C$ for 42 days. It should be noted that cooling effect of intake air was not significant because air temperature was as high as $30^{\circ}C$. Heat and aeration loss from the composter did not affect biomass decomposition by microbes during composting. Mixtures of materials with C/N ratios higher than 30 required longer composting period.

• Journal of Biosystems Engineering
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• v.29 no.6 s.107
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• pp.508-514
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• 2004

This study was conducted to investigate the influences of aeration rates and temperatures on phosphorus transformation in the manure during treatment of swine manure in 15.3L batch reactor. The total phosphorus of raw manure was composed of $91.5\%$ of inorganic phosphorus and $8.5\%$ of organic phosphorus. During the experiment, inorganic phosphorus decreased from $91.5\%\;(385.7\;mg/L)\;to\;25.8-42.7\%\;(108.8-179.8\;mg/L)$ while organic phosphorus increased from $8.5\%\;(35.6\;mg/L)\;to\;57.3-74.2\%\;(241.5-312.5\;mg/L)$. The organic phosphorus was increased by the possible transformation of soluble inorganic phosphorus to poly-phosphate by the microbial uptake. However, soluble inorganic phosphorus was not decreased much during the experiment because the insoluble inorganic phosphorus was transferred to soluble inorganic phosphorus offsetting the microbial uptake. There was no significant difference in soluble inorganic proportion variance during the experiment among treatments for three liquid temperatures and three aeration levels. In terms of phosphorus transformation in the manure and energy consumption required for aeration, lower aeration was desirable fur the manure treatment.

• KSBB Journal
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• v.8 no.4
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• pp.336-340
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• 1993

Zoogloea ramigera 115, well known type of bacteria to produce slime in sewage plants, was selected for biopolymer production. The extracted biopolymer showed high uptake capacity of metals such as cadmium and zinc. Especially the fermentor broth itself showed high adsorption of metal and could be used a biosorbent without an additional separation process. Biopolymer was immobilized into beads of calcium alginate and used in a packed bed reactor for the purpose of valued metals recovery. The biopolymer showed high removal efficiencies of 80% or greater for Cu, Cd, Mn and Zn, and high stability in sorption-desorption-resorption experiments. The immobilized biopolymer systems were found to be comparable to other metal removal systems such as ion exchange resins and to be of potential industrial application value.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.279-282
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• 2000

The effect of three antifoam agents: PPG(polypropylene glycol), PEG(polyethylene glycol) and CA-110(aquous emulsion with 16% silicon oil component), was examined on the lincomycin production during cultivation of S. lincolnensis. Both PEG and PPG were effective in foam depressing during the flask cultures. As a result, the lincomycin production was enhanced upto about 400 mg/L in a optimized medium (OP-1) containing PEG or PPG. In contrast, the effect of antifoam agents in flasks was not remarkable for the various initial concentrations ranging from 0.5 g/L to 5 g/L with the basic medium(UP-1). But the lincomycin production in small fermentor showed the great different results in comparison with that in flasks under the same conditions. The lincomycin productions in small fermentor were 325 mg/L and 130 mg/L respectively for the following initial PPG concentrations, 0.5 g/L and 1 g/L.

• KSBB Journal
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• v.20 no.6
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• pp.443-446
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• 2005

Hydrogen fermentation from food waste was attempted at different hydraulic retention time(HRT, 18-42 h). A continuous reactor fed with ground, alkali-treated and diluted food waste(average VS 4.4%) exhibited stable hydrogen production during 126 days. Hydrogen production depended on HRT, resulting in the maximum values of 25.8 mL $H_2/g\;VS_{added}$, 0.36 mol $H_2/mol\;hexose_{added}$ and 0.91 L $H_2/L/d$ at HRT 30 h. n-Butyrate and isopropanol production increased with hydrogen production increased, while acetate production decreased. The fermentation efficiency ranged from 53.3 to 65.7%, which implied that hydrogen fermentation would substitute conventional acidogenesis of food waste.

• KSBB Journal
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• v.10 no.4
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• pp.441-448
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• 1995

Optimized fermentation medium and cultural conditions for the production or exopolysaccharide KS-1 with Bacillus polymyxa KS-1 was following as; 30g g1ucose, 2.59g yeast extract, $2.5g KH_2PO_4, 0.5g NaCl, 0.3g MgSO_4.7H_20, 0.1g CaC0_3 0.05g, FeSO_4.7H_2O, and 0.05g MnS0_4 . 4H_20in 1 liter distilled water. The exopolysaccharide production was influenced by the by the temperature and pH, the optimal conditions for the production of exopolysaccharide KS-1 seemed to be $30^{\circ}C$ and pH 7.0, respectively. About $10.3g/\ell$ of maximum exopolysaccharide was obtained al the initial pH 7.0, $30^{\circ}C$, 2vvm of aeration rate and 400 rpm of impeller speed in a jar fermentor.