• Journal of Microbiology
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• v.42 no.1
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• pp.51-55
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• 2004

The influence of feedstock amino acids, salt, carbon and nitrogen sources on glutathione production by Saccharomyces cerevisiae FF -8 was investigated. Glucose, yeast extract, KH$_2$PO$_4$, and L-cysteine were found to be suitable feedstock. Highest glutathione production was obtained after cultivation with shaking for 72 h in a medium containing glucose 3.0% (w/v), yeast extract 3.0%, KH$_2$PO$_4$ 0.06% and L-cysteine 0.06%. The glutathione concentration achieved using this medium increased 2.27-fold to 204 mg/l compared to YM basal medium.

• Korean Journal of Plant Resources
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• v.17 no.1
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• pp.7-13
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• 2004

We have investigated the optimal conditions for the growth and ginsenoside production in adventitious root of “Chunpoong” (Panax ginseng C.A. Meyer). Ginseng adventitous roots induced from the embryo of “Chunpoong” were cultured in various plant media supplemented with several growth hormones. The best growth rate and high ginsenoside contents were obtained in B5 medium supplemented with IBA (2 mg/L) and kinetin (0.1 mg/L). The supplement of 2.5 mM KH$_2$PO$_4$ was good for high growth rate of the adventitious roots, but the accumulation of ginsenosides was increased by reducing the KH$_2$PO$_4$ concentration to 1.25 mM. We have established the effective liquid culture system for the optimal growth and ginsenoside production of “Chunpoong” adventitious roots.

• Journal of the Korea Institute of Building Construction
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• v.17 no.3
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• pp.211-217
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• 2017

The objective of this study is to seek a reliable mixture proportion for magnesium potassium phosphate composite(MKPC) mortars with a near-neutral pH value (below 9.5) and a relatively good compressive strength exceeding 30MPa. The main parameter selected was the molar ratios($M_{mp}$) of $MgO-to-KH_2PO_4$ which varied from 30.4 to 3.4. The setting time of the MKPC mortars tended to shorten with a decrease in $M_{mp}$ value. With regard to the strength development ratio normalized by the 28-day strength, the ranges measured in the mortars with an $M_{mp}$ below 7.9 were 50~61% at 1 day and 60~73% at 3 days, indicating a highly rapid early-strength development. With a decrease in $M_{mp}$, the formation of struvite-K crystal identified as a primary hydration product increased, which led to the decrease of the macro-capillary pores in micro-structures. For achieving the targeted requirements for pH value and compressive strength, the $M_{mp}$ needs to be selected as below 5.1.

• Korean Journal of Microbiology
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• v.32 no.3
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• pp.182-185
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• 1994

Effects of nitrogen and carbon sources on the decolorization rate of poly R-478 dye by a white rot basidiomycete Coriorus versicolor IFO 30388 were examined. The fungus exhibited 87.2% of decolorization rate when it was cultured in the state of stationary in a nitrogen-limited medium (pH 4.5) which contained 2.0% glucose, 0.04% ammonium tartrate, 0.02% poly R-478 dye, 2% $KH_2PO_4$, 0.5% $MgSO_4{\cdot}7H_2O$, 0.1% $CaCl_2{\cdot}2H_2O$, 0.002% thiamine-HCl and 10 mM 2,2 dimethylsuccinate (sodium) at $28^{\circ}C$ for 10 days. Decolorization of the dye occurred in the presence of nitrogen source in the medium and decolorization rate increased rapidly after depletion of $NH_4^+$ from the medium.

• Korean Journal of Food Science and Technology
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• v.21 no.5
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• pp.619-623
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• 1989

The cultural condition of Pseudomonas mendocina for polysaccharide production was examined. The optimal medium contains following composition per liter of distilled water: Sucrose 23.75g, $(NH_4)_2SO_4$ 1.57g, Yeast extract 0.5g, $KH_2PO_4\;2.9g,\;MgSO_4.\;7H_2O\;1.0g,\;CaCO_3$ 2.5g. The optimum temperature and pH were $30^{\circ}C$ and 6.5. At the condition. Ps mendocina produced 5.98g/l of polysaccharide. The culture viscosity after 3 days was 191mPa.s at $70sec^{-1}$. The product yield $(Y_{p/s})$ and specific productivity $(Q_p)$ were 25.18% and 32.83mg/g-cell/h.

• Microbiology and Biotechnology Letters
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• v.24 no.4
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• pp.507-511
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• 1996

Medium optimization for xylitol production from xylose by Candida parapsilosis ATCC 22019 mutant was performed. Effect of various nitrogen sources on xylitol production was investigatied. Of inorganic nitrogenous compounds, ammonium sulfate was effective for xylitol production and yeast extract was the most suitable orangic nitrogen nutrient for enhancement of xylitol production. Effect of inorganic salts such as KH$_{2}$PO$_{4}$ and MgSO$_{4}$-7H$_{2}$0 on xylitol production was also studied. Optimal medium was selected as xylose of 50 g/l, yeast extract of 5 g/l, (NH4$_{4}$)$_{2}$SO$_{4}$ of 5 g/l, KH$_{2}$PO$_{4}$ of 5 g/l, MgSO$_{4}$-7H$_{2}$O of 0.2 g/l. In a fermentor by using the optimal medium, a final xylitol concentration of 37 g/l could be obtained from 50 g/l of xylose with a xylitol yield of 74% and a xylitol productivity of 0.58 g/1-hr. At 300 g/l xylose, fermentation was also carried out and then a final xylitol concentration of 242 g/l was obtained at 272 hours. It was corresponding to xylitol yield of 80.7% and xylitol productivity of 0.58 g/1-hr.

• Journal of Life Science
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• v.13 no.4
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• pp.498-504
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• 2003

This Study was carried out to investigate the optimal mycelial growth of Pholiota nameko. The optimal medium for the mycelial growth was ME medium. The optimal temperature and pH were $25^{\circ}C$$\pm$1 and 5.5, respectively. The modified optimal medium compositions were glucose 3% (w/v), malt extract 0.25% (w/v), yeast extract 0.25% (w/v), $KH_2PO_4$ 0.046% (w/v), $K_2HPO_4$ 0.1% (w/v), $MgSO_4$ㆍ$7H_2O$ 0.05% (w/v). From the result of experiments on the optimal temperature, pH and nutritional requirements, the mycelial growth of modified optimal medium was higher than that of ME medium.

• The Korean Journal of Mycology
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• v.22 no.4
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• pp.286-297
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• 1994

The optimum nutritional and cultural conditions of polygalacturonase by Ganoderma lucidum in liquid culture were studied. The optimal temperature, pH, and the duration of culture for production of the enzyme was $30^{\circ}C$, 5.5 and 14 days, respectively. The maximal production of the enzyme was obtained in a synthetic medium containing 10 g of pectin, 10 g of soluble starch, 1 g of yeast extract, 2 g of peptone, 1 g of phenylalanine, 2 g of $KH_2PO_4$, 0.2 g of $MgSO_4{\cdot}7H_2O$, 0.05 g of $CaCI_2$ and 100 g of $thiamin{\cdot}HCI$ in 1000 ml of distilled water.

• Microbiology and Biotechnology Letters
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• v.34 no.2
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• pp.150-157
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• 2006

Bacillus sp. SMMJ-2 producing extracellular keratinolytic protease was isolated from the Swedish soils. The optimal culture conditions for production of keratinolytic protease by Bacillus sp. SMMJ-2 were investigated. The optimal medium compositions for the keratinolytic protease production were 0.7% $K_2HPO_4$, 0.2% $KH_2PO_4$, 1.0% fructose,1.2% soybean meal (roasted), and 0.01% $Na_2CO_3$. Optimal initial pH and temperature for the production of keratinolytic protease were 7.0 and 30$^{\circ}C$, respectively. The keratinolytic protease production showed a maximum of 105 units/ml/min after 72 hours cultivation under the optimal culture conditions.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.378-381
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• 2001

In the batch culture experiments, the addition of $MnSO_4$, was examined in flask culture, and then the optimal amounts of $MnSO_4$ was investigated in 2.5- L jar-fermenter. As a results, 0.005% $MnSO_4$ was found to enhance the ARA yield of 1.14- fold. Also the addition of $KH_2PO_4_4$ was investigated in 2.5-L jar-fermenter and the ARA yield was enhanced 1.20-fold. Fed batch culture study shown a relatively high productivity of cell mass (62.1 g/L) and ARA content (12.0 g/L) when 14% ammonia solution were alternatively used to control the pH and nitrogen source in the cultivation period.