• The Korean Journal of Food And Nutrition
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• v.13 no.2
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• pp.171-175
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• 2000

Microbial proteases have certain unique characteristics, and are now widely used in food, leather, detergent, and pharmaceutical industries. Thermophilic Actinomyces producing the protease was isolated from soil in Wonju city. This strain was able to grow and produce protease at the culture temperature of 50$^{\circ}C$. The maximum protease production was obtained when 0.5% soluble starch and 0.4% yeast extract were used as carbon and nitrogen source, respectively. The other culture condition for the maximal productivity of the protease was 0.1% K2HPO4, and 0.05% CaCl2 at initial pH 8.0 for 48 hours.

• KSBB Journal
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• v.16 no.2
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• pp.207-211
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• 2001

Statistical experimental design methods were employed to select the cultivation factors influencing latic acid production during the fermentation of kitchen refuses. Working volume and pH swings were identified as the main factors affecting lactic acid production. Optimum pH swing was pH 7.8 and working volume was 125 mL in a 250 mL flask. Under optimum condition, lactic acid was produced at 21.8 g/L, which was 6.2 times higher than produced during uncontrolled fermentation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.5
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• pp.856-862
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• 1994

In salt-preserved foods of every kinds, it was examined the growth condition of halophilic bacteria that induced a change of colour, taste, nutritive substance, a production condition of enzyme and a character of crude enzyme. Used bacteria is H. halobium a kind of extremely halophilic bacteria, and the required of optimum culture needed a quite long time of crude enzyme production is 168 hours. Optimum pH is about 7-7.5, so the traditional food of such neutrality pH as soybean paste and soy sauce particularly come into trouble because the growth can flourish in neutrality or alkaliescence, and the crude enzyme also appeared that best activation between pH 6 and pH 8. The optimum temperature is about 37$^{\circ}C$, the optimum temperature of enzyme is about 40 $^{\circ}C$ and the temperature stability is settled for 15 minutes and it is completely inactivated at 10 minutes. In the influence of each metal ion, Fe++ and Mn++ a stimulated the growth of H.halobium and the activation of enzyme, Cu++ and Zn++ were identified that made the growth and the activation of enzyme inhibit.

• Microbiology and Biotechnology Letters
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• v.17 no.5
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• pp.468-474
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• 1989

The cultural condition for polysaccharide production by Pseudomonus detafietdii was studied. The optimal medium contains the following composition per liter of distilled water: glucose (25g/$\ell$), peptone (2.06g/$\ell$), KH$_2$PO$_4$(2g/$\ell$), MgSO$_4$.7$H_2O$ (2g/$\ell$), yeast extract (0.5g/$\ell$), CaCO$_3$(2.5g/$\ell$). The temperature and pH optimum were 3$0^{\circ}C$ and 6.5. The agitation speed was 300 rpm. 5.91g of polysaccharide was produced at the condition in flask culture.

• Plant Resources
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• v.5 no.1
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• pp.78-85
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• 2002

The material of Rhodiola sachatinensis collected from an alpine region of the west-northern China. For analysing the effect, 1 used Rhodiola sachatinensis's rhizome and cultivated callus. In EtOAc, BuOH, $H_2O$ separation the plant showed strong antioxidative activity, but not in Hexane. The radical scavenging effect of EtOAc(RC$_{50}$,35(g), BuOH(RC$_{50}$, 43(g), H$_2$0(RC$_{50}$, 50(g) fraction and MeOH extract(RC$_{50}$, 50(g) of the Rhodiola sachatinensis was comparable to that of synthetic antioxidant BHA(RC$_{50}$, 14(g) and $\alpha$-Tocopherol(RC$_{50}$, 12(g). Total amino acid concentration of plant of In nature condition were 18,009ppm, and major components were arginine, glutamic acid, aspartic acid and valine. The ratio of essential/total amino acid on plant of In nature condition was 46.93%. Total amino acid concentration of callus of In vitro condition were 32,435ppm, and major components were valine, histidine, lysine and leucine. The ratio of essential/total amino acid on callus of In vitro condition was 56.07%. was 56.07%.

• 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.

• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.393-397
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• 2003

P. aeruginosa F722 produces biosurfactant (BS) while degrading hydrocarbons. BS production was 0.78 $g/{\ell}$ on the C-medium. However, BS production increased by 1.66 $g/{\ell}$ on the condition of 0.05% (w/v) $NH_4Cl+0.1%$ (w/v) yeast extract and 3.0% (w/v) glucose, which was proved to be advantageous to BS production. In the condition of aeration of 1.0 liter per minute (LPM), BS production was increased 20% (1.94 $g/{\ell}$)more than 1.66 $g/{\ell}$ produced when the air was not supplied. Moreover, the velocity of glucose degradation at both of log and stationary growth phases increased from 0.25 and 0.18 $h^{-1}$ to 0.33 and 0.29 $h^{-1}$ respectively when the air was supplied. Besides, BS activity was more stabilized on the condition of air supply.

• Journal of Life Science
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• v.18 no.10
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• pp.1410-1414
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• 2008

This study was carried out to develop a vinegar by an onion juice. Onions are considered to be a promising source of the vinegar because these are rich in sugars, amino acids and various nutrients. An Acetobacter for an acetic acid fermentation was isolated and used from vinegars produced by industrial goods or from matured Kimchi. When supplemented with 2-8% ethanol into an onionic juice medium, the highest production of the acetic acid was observed at 9 days by addition of 4% ethanol. Optimum temperature and aeration for acetic acid production were exhibited at $30^{\circ}C$ and 200 rpm, respectively. A flask containing larger air-contact surface region for fermentation was produced the more acetic acid than that of a test tube. Taken all these together, an optimum condition for the acetic acid fermentation was over 9 days at $30^{\circ}C$, 200 rpm with 5% alcohol and 2% initial acidity. When fermented by the upper condition, the final product contains 5.2% total acidity and less than 1% ethanol. These are suitable for conditions of fruit vinegar notified by the Ministry of Commerce, Industry and Energy.

• Journal of Microbiology and Biotechnology
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• v.30 no.8
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• pp.1235-1243
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• 2020

The use of microalgal biomass as feedstock for biofuels has been discussed for decades as it provides a sustainable approach to producing fuels for the future. Nonetheless, its feasibility has not been established yet and various aspects of biomass applications such as CO₂ biofixation should also be explored. Therefore, in this study, the CO₂ biofixation and lipid/carbohydrate production potential of Chlorella sp. ABC-001 were examined under various nitrogen concentrations. The highest biomass productivity and CO₂ biofixation rate of 0.422 g/l/d and 0.683 g/l/d, respectively, were achieved under a nitrogen-rich condition (15 mM nitrate). Carbohydrate content was generally proportional to initial nitrate concentration and showed the highest value of 41.5% with 15 mM. However, lipid content showed an inverse relationship with nitrogen supplementation and showed the highest value of 47.4% with 2.5 mM. In consideration as feedstock for biofuels (bioethanol, biodiesel, and biogas), the sum of carbohydrate and lipid contents were examined and the highest value of 79.6% was achieved under low nitrogen condition (2.5 mM). For lipid-based biofuel production, low nitrogen supplementation should be pursued. However, considering the lower feasibility of biodiesel, pursuing CO₂ biofixation and the production of carbohydrate-based fuels under nitrogen-rich condition might be more rational. Thus, nitrogen status as a cultivation strategy must be optimized according to the objective, and this was confirmed with the promising alga Chlorella sp. ABC-001.

• Journal of Korean Society of Environmental Engineers
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• v.37 no.6
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• pp.363-370
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• 2015

The production of polyhydroxyalkanoates (PHAs) using Sequencing Batch Reactor (SBR) was investigated. The experiments were performed in two fabricated SBRs (4 L) of different oxidation state. Synthetic wastewater was used as substrate, using C/N/P ratio of 42:10:1. SBR 1 and SBR 2 were operated in aerobic dynamic feeding (ADF) and anaerobic/oxic dynamic feeding (AODF) condition, respectively. ADF provide feast and famine in aerobic condition, while AODF in anaerobic/oxic condition. PHAs production was found high in AODF than AOF. Maximum PHAs content of 40.0% (w/w)of biomass were produced in AODF mode. Produced PHAs structural and thermal property were good.