• 한국생물공학회:학술대회논문집
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• 2005.10a
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• pp.495-495
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• 2005

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.spc1
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• pp.123-131
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• 2005

Lipid and protein contents in whole soybean seeds have negative correlation (r=-0.693**), however, these components in seed coat showed positive correlation (r=0.746**). Fatty acids in whole soybean seeds were higher in the order of $C_{18:2}>C_{18:1}>C_{16:0}>C_{18:3}>C_{18:0}$, while those of seed coat were higher in the order of $C_{18:3}>C_{18:2}>C_{18:0}>C_{16:0}>C_{18:1}$. The average content of total amino acid in twenty Korean soybean varieties was 38,938.7 mg/100 g, while that of seed coat was 4,418.4 mg/100g. Glutamic acid showed the highest composition rate $(16.4\%)$ in whole soybean seeds, while glycine was the highest in seed coat and their composition rate was $23.8\%$. The surface of shiny-lustre seed coats was smooth and their pore size was observed smaller than dull-lustre ones. Significant quadratic regression was observed among seed coat lightness, seed coat thickness, protein, lipid, unsaturated fatty acid and crude fiber. Fucose, rhamnose, glucose, mannose, galactose, arabinose and xylose were detected as a neutral mono-saccharides in the seed coats. The arabinose and xylose showed significant correlation with seed coat lightness. The unsaturated fatty acid was significantly correlated with seed coat lightness (r=0.726**). Water absorption rate was low in the thick seed coat varieties, but the rate was high in the shiny seed coat varieties. From the obtained results, it was considered that the thinner and brighter seed coat varieties were much favorable to increase the water absorption rate than thicker and darker seed coat ones.

• Journal of Microbiology and Biotechnology
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• v.4 no.1
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• pp.56-62
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• 1994

A yeast strain, BT001, which can directly ferment D-xylose to ethanol was isolated from forest soils, and then identified as Candida sp. Cultural conditions for the optimum ethanol production, along with the effects of aeration on cell growth and ethanol production were investigated. Aeration stimulated the cell growth and the volumetric rate of ethanol production, but decreased the ethanol yield. Optimum temperature and initial pH for the ethanol production were $33{\circ}^C$ and 6.0, respectively. In a shake flask culture, this strain produced 52.3 g ethanol per liter from 12%(w/v) D-xylose after incubation for 96 hours. Ethanol yield was 0.436 g per g D-xylose consumed. This corresponds to 85.8% of theoretical yield. Also, this yeast strain produced ethanol from D-galactose, D-glucose and D-mannose, but not from L-arabinose and L-rhamnose. Among these sugars, D-glucose was the fastest in being converted to ethanol sugars.

• Microbiology and Biotechnology Letters
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• v.25 no.5
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• pp.490-494
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• 1997

A variety of microbial strains isolated from soil were tested for their ability to produce D-tagatose from D-galactose. An organism that can convert D-galactose into D-tagatose was selected and was identified as Enterobacter agglomerans. The cells grown on the induction medium containing 20 g/l arabinose were found to the best conversion potential among different carbohydrates and the conversion yield was about 15% when 20 gll galactose was used. The isolated crystals were obtained from the culture broth after the purification process such as treatment of ion resins, crystallization, and drying. The recovery yield was 70% after the purification. The crystals were identified as D-tagatose by the infrared spectroscopy, HPLC, specific optical rotation, and melting point.

• Microbiology and Biotechnology Letters
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• v.8 no.3
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• pp.173-180
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• 1980

A source of D-xylose was required for the enhanced production of D-glucose isomerase of Streptomyces sp. strain K-17. D-glucose supported the luxuriant growth of the organism as well as D-xylose, but D-glucose isomerase activity was hardly detected in the D-glucose-grown cells. When the D-glucose-grown cells were incubated aerobically for a few hours in 0.5% xylose solution in 0.05 M phosphate buffer, pH 7.0, it was found that inductive formation of D-glucose isomerase occurred in the cells without multiplication. In the non-growth phase of cells the inductive formation of D-glucose isomerase occurred because a source of nitrogen for the synthesis of enzymes was obtained from turnover of protein accumulated in cells. D-ribose, L-arabinose, D-glucose, D-mannose, citrate, succinate and tartrate could not induce the formation of D-glucose isomerase, but D-xylose could induce. Inductinn of D-glucose isomerase was repressed by D-glucose and its catabolites : glycerol, succinate and citrate. Inductive formation of the enzymes in the non-growth phase was stimulated by $Ba^{2+}$, $Mg^{2+}$ and $Co^{2+}$, and inhibited by C $u^{2+}$, C $d^{2+}$, A $g^{+}$and H $g^{2+}$. The synthesis of enzymes in the induction system composed of 0.5% xylose solution was disrupted by actinomycin D, streptomycin, chloramphenicol, kanamycin, tetracycline, p-chloromercuribenzo ate, arsenate and 2, 4-dinitrophenol, but not disrupted by mitomycin C and penicillin G.icillin G.

• Journal of Microbiology and Biotechnology
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• v.20 no.6
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• pp.1018-1021
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• 2010

Metallic and non-metallic isomerases can be used to produce commercially important monosaccharides. To determine which category of isomerase is more suitable as a template for directed evolution to improve enzymes for galactose isomerization, L-arabinose isomerase from Escherichia coli (ECAI; E.C. 5.3.1.4) and tagatose-6-phosphate isomerase from Staphylococcus aureus (SATI; E.C. 5.3.1.26) were chosen as models of a metallic and non-metallic isomerase, respectively. Random mutations were introduced into the genes encoding ECAI and SATI at the same rate, resulting in the generation of 515 mutants of each isomerase. The isomerization activity of each of the mutants toward a non-natural substrate (galactose) was then measured. With an average mutation rate of 0.2 mutations/kb, 47.5% of the mutated ECAIs showed an increase in activity compared with wild-type ECAI, and the remaining 52.5% showed a decrease in activity. Among the mutated SATIs, 58.6% showed an increase in activity, whereas 41.4% showed a decrease in activity. Mutant clones showing a significant change in relative activity were sequenced and specific increases in activity were measured. The maximum increase in activity achieved by mutation of ECAI was 130%, and that for SATI was 190%. Based on these results, the characteristics of the different isomerases are discussed in terms of their usefulness for directed evolution of non-natural substrate isomerization.

• YAKHAK HOEJI
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• v.42 no.2
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• pp.196-204
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• 1998

The blood-brain barrier (BBB) of rats was modificated opening reversibly by infusing a hyperosmotic solution of arabinose (1.6 molal) into the right external carotid artery. Pre vious studies demonstrated that permeability was increased maxmmally in the first 15 min and remained slightly elevated at 1 hr. As control reference, saline was used. In the present study, to evaluate the effects of osmotic BBB opening on the BBB trasport according to hydrophilic or hydrophobic characteristics of drugs. And the differences of the uptakes of these compounds to right (treated osmotic opening) and left (untreated) hemispheres in same rats were compared each other following injection of 8 mCi per rat of $^{99m}Tc$-ethylene triamine pentaacetic acid (DTPA) as hydrophilic drug or 5mg/kg of phenytoin as hydrophobic drug mto the right external carotid artery of rats between two groups (1.6 molal arabinose vs saline). The uptakes of $^{99m}Tc$-DTPA and phenytoin in the right cerebral hemispheres were increased to about thirty three times and twice rather than those in the left cerebral heimspheres, respectively. And PAs (permeability X capillary surface area) were also increased from a control mean of 2.11${\times}10^{-4}$ (Untreated) to 6.98${\times}10^{-3}\;sec^{-1}$ (treated osmotic opening for $^{99m}Tc$-DTPA and 0.29 to 0.17 $sec^{-1}$ for phenytoin, respectively. From the results of present study, it is noted that osmotic opening of BBB is more effective in the brain delivery of hydrophilic drugs rather than that of hydrophobic drugs.

• Journal of the Korean Wood Science and Technology
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• v.24 no.3
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• pp.28-36
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• 1996

This experiment was carried out to elucidate the sugar composition of polysaccharides and the structural features of water-soluble polysaccharides(WSP) isolated from Korean oak mistletoe, Loranthus yadoriki Sieb. The 48-hours ball-milled meals of extractive-free dried mistletoe sawdusts were extracted with distilled water for $24hrs{\times}2$ at room temperature. The extracts poured into 95% ethyl alcohol to precipitate. The separated precipitate of WSP, in form of yellowish white powder by lyophilization, was fractionated into four subfractions of WSP-1, WSP-2, WSP-3 and WSP-4 by anion exchange chromatography on DEAE-cellulose column. The sugar composition of WSPs was analyzed by GLC in form of their glycitol acetates, and the structure of polysaccharides in Fractions WSP-1 and WSP-2 was determined by FT-IR and GC-MS after methylation through and acetylation. The sugars of WSPs from Korean oak mistletoe, Loranthus yadoriki, are majorly arabinose and galactose in stem, galactose in leaves very high in content and showed difference in composition and monomeric units between stems and leaves. D-galactose, D-glucose and L-arabinose are the simple sugars consisting of polysaccharides in WSP-1. ($1{\rightarrow}3$)-Linked galactan is the bakcbone with side chain of ($1{\rightarrow}5$)- -L-arabinofuranosyl residues and ($1{\rightarrow}6$)- -D-galactopyranosyl residues, and ($1{\rightarrow}4$)-linked glucan also presents. ($1{\rightarrow}4$)-Linked rhamnogalacturonan and ($1{\rightarrow}4$)- and ($1{\rightarrow}3$)-linked galactan present in WSP-2.

• Proceedings of the Zoological Society Korea Conference
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• 1997.10b
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• pp.241.1-241
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• 1997

No Abstract, See Full Text

• Korean Journal Plant Pathology
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• v.12 no.1
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• pp.109-115
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• 1996

국내 감자 연작 재배지에서 수집하여 분리동정한 더뎅이병원균인 Streptomyces scabies의 배양적, 형태적, 생리적 특성을 조사한 결과는 다음과 같다. 이병감자에서 분리된 균들은 병원성 균주와 비병원성 균주들로 구분되었고, 이들 간에는 뚜렷한 차이를 보였는데, 전형적인 병징을 나타내는 병원성균주는 비병원성균주와는 달리, 나선형의 포자사슬, 회색 포자, 멜라닌 색소를 생성하고 D-glucose, L-arabinose, D-fructose, D0mannitol, raffinose, rhamnose, sucrose, i-inositol, D-xylose 등의 탄소원을 이용하였으며, 또한 7% NaCl 및 streptomycin sulfate, crystal violet, olean domycin(10$\mu\textrm{g}$/ml, 100$\mu\textrm{g}$/ml)등의 항생물질에 감수성을 나타내었다.