• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.735-738
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• 2001

Metabolically engineered Escherichia coli strains harboring a plasmid containing a novel artificial polyhydroxyalkanoate (PHA) operon consisting of the Aeromonas PHA biosynthesis related genes and Ralstonia eutropha reductase gene were developed for the production of poly(3-hydroxybutyrate-co-hydroxyhexanoate) [P(3HB-co-3HHx)] from dodecanoic acid. By applying stepwise reduction of dissolved oxygen concentration (DOC) during the fermentation, the final dry cell weight, PHA concentration, and PHA content of 79 g/L, 21.5 g/L, and 27.2 wt%, respectively, were obtained in 40.8 h, which resulted in the PHA productivity of 0.53 g/L/h. The 3HHx fraction slowly increased during the fed-batch culture to reach a final value of 10.8 mol%. The 3HHx fraction in the copolymer could be increased by three fold when the Aeromonas hydrophila orfl gene was co-expressed with the PHA biosynthesis genes.

• 한국생물공학회:학술대회논문집
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• 2003.10a
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• pp.324-327
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• 2003

The effects of sugar on secretion of total protein and protease into the medium were investigated in transgenic tobacco cells. The dry cell weight reached 14.62 g/L. At 60 g/L sugar and 10day, the maximum concentration tested. the total protein, protease was present in the culture medium at 68.6 mg/L, 3645 U/L.

• Journal of Plant Biology
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• v.13 no.4
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• pp.13-22
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• 1970

The rice variety, Kwanok, was reared in the water, land and salt seed beds and transplanted to the reclaimed soil area having an average of 0.48% salt content (0.67% at the end of April). The plant height of land bel seedlings at transplanting stage was short but the dry-weight/plant-height ratio was large and the rooting ability was vigorous remarkably after transplantation in the salty area. The central cylinder, vessels, sclerenchyma, endodermis and other mechanical tissues of the root of land bed seedlings were well developed while the size of cortical cell layers were small. The cytoplasm of the cortical parenchyma at the root tips seemed to be most abundant in the land bed seedlings. The formation of the aerial cavity in the cortex of primary root was rapid and it seemed that the developmental mechanism of the aerial cavity in the rice plant roots was related to the development of the lateral roots.

• Journal of Microbiology and Biotechnology
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• v.4 no.4
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• pp.338-342
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• 1994

The bacterium producing EPA was isolated from the intestines of the marine fishes. The strains were studied for their identification and their culture conditions. The selected strain was gram negative, rod(0.7 $\times$ 2.4 $\mu m$ in size) and motile with a single polar flagellum. This strain was identified as a Pseudomonas sp. on the basis of its morphological, cultural and physiological characteristics. The strain showed a maximum productivity of phospholipid at $20^{\circ}C$ after 48 hours of culture time with an initia1 pH of 7.0 in the PYM-glucose medium. Under these culture conditions, the production of phospholipid was about 0.3 mg/ml and 0.06 mg/mg dry cell weight.

• Microbiology and Biotechnology Letters
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• v.23 no.5
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• pp.531-535
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• 1995

The identification of eicosapentaenoic acid (EPA) by Pseudomonas sp. CH-414 were investigated under the optimal culture conditions. The maximum dry cell weight and phospholipid production showed about 10 mg/ml and 0.6 mg/ml, respectively, at the 48 hr cultivation. The phospholipid form produced by Pseudomonas sp. CH-414 was elucidated as a phosphatidyt ethanolamine by thin layer chromatography. EPA was contained about 15% in the. extractable lipid, and the amount of EPA was about 83 $\mu $g/ml from the culture broth. Also myristic, palmitic, palmitoleic, stearic and oleic acids were identified with gas chromatography.

• Journal of Microbiology and Biotechnology
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• v.21 no.10
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• pp.1081-1087
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• 2011

An internally radiating photobioreactor was applied for the production of astaxanthin using the unicellular green alga Haematococcus pluvialis. The cellular morphology of H. pluvialis was significantly affected by the intensity of irradiance of the photobioreactor. Small green cells were widespread under lower light intensity, whereas big reddish cells were predominant under high light intensity. For these reasons, growth reflected by cell number or dry weight varied markedly with light conditions. Even under internal illumination of the photobioreactor, light penetration was significantly decreased as algal cells grew. Therefore, we employed a multistage process by gradually increasing the internal illuminations for astaxanthin production. Our results revealed that a multistage process might be essential to the successful operation of a photobioreactor for astaxnthin production using H. pluvialis.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.3
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• pp.246-252
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• 1991

Marine baceteria of fish interstines were screened for high eicosapentaenoic acid(EPA) productivity. An isolated bacteria, KS-90, identified and designated as Allteromonus putrefaciens KS-90. A. putrefaciens KS-90 was found to be a rich source of EPA production and it was observed on incuibation at 4~12.5$^{\circ}C$ and pH 7.0. The production of EPA reached 18mg/g of dry cell weight when A. putrefaciens KS-90 was grown in the medium containing 1.0% pepton, 0.5% yeast extract, 0.025% meat extract and 2.0% glucose in 1/2 concentration of an artificial seawater, pH for 48 hr at $25^{\circ}C$. This value accounted for 24.7% of the total fatty acid in the extractable lipids.

• Journal of Hydrogen and New Energy
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• v.24 no.4
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• pp.275-281
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• 2013

This study was conducted to increase the amount of bio-hydrogen production from microalgae(Chlorella vulgaris) in batch reactors by thermal pre-treatment. The optimization of thermal pre-treatment was conducted using statistic experimental design of response surface methodology. Two experimental parameters of temperature and reaction time were considered. The optimization condition was founded at the coded variables of <0.52, -0.07> corresponding to the experimental of heating temperature of $95.6^{\circ}C$ and reaction time of 57.9 min, respectively. Under the optimal condition, the maximum hydrogen production was predicted to 25.3mL $H_2/g$ dry cell weight (dcw), which was 9.1 times higher value of control(2.8mL $H_2/g$ dcw).

• KSBB Journal
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• v.14 no.3
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• pp.380-383
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• 1999

During the biodesulfurization of dibenzothiophene to 2-hydroxybiphenyl by Rhodococcus erythropolis IGTS8, a surfactant-like substance was secreted into the medium resulting in the decrease of the surface tension of the medium. Due to the substance, the optical density (at 600 nm) of the medium had no co-relation with dry cell weight during cultivation. The growth rate of IGTS8 increased by the addition of 1 % Tween 80, but it was inhibited over Tween 80 concentration of 2 % (v/v).

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.157-160
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• 2002

Probiotics can form profitab1e microorganisms in human or animal internal organs. When it is fed at domastic animals, can bring the rise of weight and prevention of disease. Pichia anonwla by new probiotics have antibiotic effect and oder reducing effect. we researched about optimal condition of pilot scale fermentation and freezed dry of pichia anonwla.