• Microbiology and Biotechnology Letters
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• v.26 no.3
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• pp.244-249
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• 1998

An extracellular polysaccharide, methylan, was produced under the specific conditions by Methylobacterium organophilum from methanol. The specific growth rate of cells was approximately constant regardless of C/N ratio and the specific product yield was maximum at a C/N ratio of 30. Methylan production was suppressed by the deficiency of mineral ions such as Mn$^{++}$ or Fe$^{++}$ ion. The optimal pH for cell growth and methylan production was 7. Whereas the optimal temperature for cell growth was found to be 37$^{\circ}C$, that for methylan production was 3$0^{\circ}C$. The methanol concentration above 4% completely inhibited the cell growth. The initial methanol concentration for the maximal production of methylan was 0.5% (v/v) and above this concentration, methylan production was markedly inhibited. To overcome the substrate toxicity and inhibition for both cell growth and methylan production, a fed-bach culture of intermittent feeding within 5 g/l methanol was conducted under the optimal culture condition. Methylan production of was stimulated by nitrogen limitation and methylan was accumulated up to 8.7 g/1 and cell mass also increased up to 12.4 g/l.

• Journal of Korea Foundry Society
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• v.20 no.2
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• pp.97-103
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• 2000

In this study, a design of experiment, Taguchi method, was applied to optimize gating system design of escalator step die casting parts. Six shape factors which affect filling sequence of melt are adopted and divided into two levels respectively. Initial feeding differences of melt which were calculated by using S/N(signal-to-noise) ratio in each condition were demonstrated with the simulation of Flow-3D software program. Variations of S/N ratio according to shape factors were obtained and the optimal condition of gating system could also be obtained. It could be found that width of gate, contact angle of gate, thickness of runner are more effective factors on the filling sequence of melt than the others in this case of escalator step die casting parts. It showed that the economical gating system and sound filling sequence of melt were obtained by using Taguchi method.

• Journal of Korean Society on Water Environment
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• v.21 no.3
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• pp.284-288
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• 2005

In this study, photochemical advanced oxidation processes (AOPs) utilizing the Photo Fenton reaction ($Fe^{2+}+H_2O_2+UV$) were investigated in lab-scale experiments for the treatment of livestock wastewater. For the experimets, the livestock wastewater was pretreated by coagulation with $3,000mg/L\;FeCl_3$. The optimal conditions for Photo-Fenton processes were determined: pH was 5, the concentration of ferrous ion (Fe II) was 0.01 M. The concentration of hydrogen peroxide was 0.1 M, and molar ratio ($Fe^{2+}/H_2O_2$) was 0.1. The optimal reaction time was 80 min. Under the optimal condition of Photo-Fenton process, chemical oxygen demand (COD), color and fecal coliform removal efficiencies were about 79, 70, and 99.4%, respectively and sludge production was 7.5 mL from 100 mL of solution.

• Journal of Microbiology and Biotechnology
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• v.1 no.4
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• pp.288-292
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• 1991

The aim of the current study is to evaluate the effects of medium compositions on the production of protease inhibitor in Streptomyces sp. SMF13. The production of protease inhibitor was counter-currently linked to extra-cellular protease, which were regulated by the culture conditions. Nitrogen source was the most critical ingredient affecting the production of protease inhibitor and protease. Carbon source was an important factor to determine the culture pH which affected very clearly the formation of protease and protease inhibitor. Inorganic phosphate inhibited the protease inhibitor production which was linked to the cell growth rate, although the optimal conditions for the production of protease inhibitor were not favouring to the cell growth.

• Applied Biological Chemistry
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• v.46 no.4
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• pp.348-352
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• 2003

In this study, strain of high-producing intracellular glutathione was isolated from Korean traditional rice wine. The isolated strain was identified as Saccharomyces cerevisiae based on the morphological, physiological and biochemical characteristics, and was designated as FF-8. The optimal condition for glutathione production by Saccharomyces cerevisiae FF-8 was obtained after cultivation with shaking for 72 hours in the YM medium. The optimal temperature, shaking rate and initial pH for the glutathione production were $30^{\circ}C$, 100 rpm and pH 6.0, respectively. The dry cell weight and glutathione concentration produced by Saccharomyces cerevisiae FF-8 were 5.2 g/l and 72.0 mg/l, respectively, under the optimal culture condition.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.4
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• pp.493-498
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• 2006

The optimal culture conditions of Monascus purpureus MMK2 for production of red pigment were investigated in submerged culture. Monascus purpureus MMK2 showed a maximal production of red pigment in the medium containing of 3.0% wheat flour, $0.15%\;NaNO_3,\;0.25%\;Na_2HPO_4\;12H_2O$ and $0.15%\;MgSO_4\;7H_2O$. The optimal culture conditions of temperature and initial pH were $30^{\circ}C$ and 6.5, respectively. The red pigment production reached to a maximal level at 7th day of cultivation.

• Microbiology and Biotechnology Letters
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• v.34 no.3
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• pp.250-256
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• 2006

The optimum cultural conditions for production of Monascus natural pigment by Monascus purpureus MK2 were investigated in submerged culture. This strain was showed the maximum production of monascus natural pigment in the optimal medium of 3.0% wheat flour, 0.15% $NaNO_3$, 0.2% $K_{2}HPO_4$ and 0.05% $MgSO_4{\cdot}7H_{2}O$, at pH 7.0. The maximum production of this pigment was achieved at $30^{\circ}C$ for 7 day cultivation under 130 rpm shaking. At optimal condition, Monascus purpureus MK2 produced 29.10, 36.84 and 48.92 units of yellow, orange and red pigment, respectively.

• Korean Journal of Pharmacognosy
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• v.27 no.4
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• pp.289-294
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• 1996

In previous paper, we described the induced callus of Corydalis remota contains a significant amount of alkaloids. This study describes an optimal condition to maximize alkaloid production. The suspension cultures maintained alkaloid production ability after fifth subculture and a small amount of alkaloid seemed to be released out of cells. The yields of alkaloid by cultured cells was varied depending on the concentrations of NAA, carbon sources and phosphate ion and depending on the vitamin combinations and concentrations. Biosynthetic precursor and an elicitor treatment also affected the total alkaloid yield of the cultures. The optimal conditions for alkaloid production were as follows: 1) MS basal salt containing 30 g/l of glucose, 1.0 mg/l of NAA, and vitamins of LS medium should be used. 2) The culture should be treated with tyrosine 20 mg/l, and yeast extract 1.5 ml/l after the culture reached a stationary phase of growth. Five alkaloids were isolated from the cultures and they were characterized. The spectral data unambiguously revealed that the isolated compounds were dihydrosanguinarine, protopine. tetrahydropalmatine, allocyptopine and ambinine, respectively.

• Microbiology and Biotechnology Letters
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• v.20 no.2
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• pp.183-189
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• 1992

Cultural conditions of Lactococcus sp. 1112-1, a bacteriocin producing strain, were studied for enhancing its production with regard to environmental and nutritional factors. Optimal compositions of culture medium for bacteriocin production were glucose 20 g/l as carbon source, casein acid hydrolyzate 15 g/l as nitrogen source, and sodium acetate 3 g/l, ammonium citrate 2 g/l as morganic salt with other basal components. The optimal pH of medium and fermentation temperature were 6.2 and $35^{\circ}C$, respectively. This strain required exclusively riboflavin and pantothenic acid for growth and bacteriocin production. In a 1l batch culture, stationary phase emerged after 8.5 hours of fermentation when 1.81 g/l of biomass was accumulated. The maximum antimicrobial activity was 3,894 IU/ml after 12 hours.

• Food Science and Preservation
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• v.11 no.1
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• pp.111-116
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• 2004

The optimum cultural conditions for production of red pigment from Monascus rubber KCTC 6122 is liquid culture were studied. Monascus robber KCTC 6122 was shown to give the maximum production of red pigment in the medium containing 4％ rice powder, 0.2％ NaNO$_3$, 0.3％ Na$_2$HP0$_4$ and 0.15％ MgSO$_4$. The optimum culture conditions, temperature, initial pH and shaking speed were 30$^{\circ}C$, 6.5 and 150 rpm, respectively. The red pigment production reached a maximum level at 8days of cultivation.