• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2006.10a
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• pp.120-121
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• 2006

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.6
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• pp.998-1004
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• 1995

This study was carried out in order to investigate the browning reaction of fish oil-amino acid model system at different temperatures and watger activities. The 23 amino acids, induced during dehydration in the presence of oil and avicel(5 to $45^{\circ}C$), Aw 0.33 to 0.95, were resulted in three types of browning patterns : Type I showed high browning rates at Aw 0.33, 0.95 than at Aw 0.52, 0.75(phenylalanine, trans-4-hydroxy-L-proline, methionine, valine). Type II showed high browning rates decreased with increasing water activity(poline, leucine, isoleucine, arginine). Type III showed high browning rates at Aw 0.52, 0.75 than at Aw 0.33, 0.95(tryptophan, cystein, threonine, lysine). The temperature effect on the browning development of the four most active amino acids : phenylalanine, valine, trnas-4-hydroxy-proline and methionine are shown to represent the 23 amino acids. Above $25^{\circ}C$ the browning rate began to increase. Activation energy of the amino acids-fish oil was 8 to 40kcal/mole, and $Q_{10}$ were 2 to 10.

• YAKHAK HOEJI
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• v.37 no.4
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• pp.389-396
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• 1993

An Actinomycetes strain JB isolated from Mt. Hanla had a strong antimicrobial activity against gram positive bacteria and tumor cell growth inhibition. Especially, it couldn't degrade starch and casein as organic compounds. It was resist on lincomycin and rifampicin. The spore mass of strain JB which was arethrospore was white. DAP of the cell wall was L, L-DAP. Antimicrobial material was heat stable, dissolved in ethyl acetate, and not dissolved in butanol. In the pressnce of 0.1% phenol and 4% sodium chloride, strain JB could grow, but it didn't growth at below $10^{\circ}C$. Strain JB didn't use dextran, sodium acetate and sodium citrate as sole carbon source and L-cystein and L-thereonine as nitrogen source. The filtered broth of strain JB had the antimicrobial activity against gram positive bacteria, especially Staphylococcus aureus (ATCC 65389) and the growth inhibition of tumor cell line.

• Journal of Microbiology
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• v.35 no.2
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• pp.97-102
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• 1997

Cysteine desulfhydrase (EC 4.4.1.1.) was purified from the culture supernatant of Streptomyces albidoflavus SMF301 by hydroxyapatite, gel filtration and Resource Q ion-exchange chromatography with a purification fold of six identical subunits. The enzyme was stabilized by dithiothreitol and pyridoxal 5'-phosphate during the purification procedures. The optimum pH and temperature were pH 8.6 and 35$^{\circ}C$, respectively. The N-terminal amino acid sequence was identified as A-P-L-P-T-A-D-V-R-S-D-P-G-Y-R-E-W-L-G-E-A-V. The purified cystein desulfhydrase had a high substrate specificity toward cysteine, and exhibited no cystahionine $\gamma$-lyase activity. The $K_m$ value for cysteine was determined to be 0.37 mM.

• Journal of Life Science
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• v.9 no.1
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• pp.9-13
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• 1999

Reduced thiols were important compounds for the maintenance of leukemia and lymphoma cell survival (and growth). In the course of examining the microenvirn-mental effects on lymphoma and leukemia cell growth, we found that cysteine suppressed apoptosis in these cells. In a present study, in order to investigate the role of cystein on the suppression of apoptotic cell death, we used CS21, P388, and L1210 cell lines. The addition of BSO, an inhibitor of glutathione synthase, induced apoptosis of these cells by blocking the cellular uptake of cysteine in CS21 cells. Although L1210 cells underwent apoptosis without thiol compounds, the addition of these compounds suppressed the apoptosis and promoted the growth or L1210 cells. When specific inhibitors of caspase3-like proteases, but not caspase1-like proteases, were activated during the L1210 cell apoptosis but the addition of thiol compounds suppressed the activation of caspase3-like proteases. These results suggest that reduced thiols including cysteine play an important role in the suppression of cell apoptosis by inhibiting the activation of caspase3-like proteases.

• YAKHAK HOEJI
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• v.51 no.3
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• pp.199-205
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• 2007

Thermostable asparaginase was purified to homogeneity from mesophilic Strepfomyces lincolnensis M-20 by 30${\sim}$70% ammonium sulfate precipitation and asparagine-Sepharose CL 6B affinity column chromatography, The apparent molecular mass of L-asparaginase by SDS-PAGE was found to be 47 kDa, whereas by its mobility on Sephacryl S-300 column was around 180 kDa, indicating that the enzyme at the native stage acts as tetramer, The purified enzyme showed a single band on acrylamide gel electrophoresis. The optimum pH and temperature were pH 9.5 and 55${\circ}$C, respectively. Chemical modification experiments of purified asparagines implied the existence cystein residue located at or near active site. Purified asparaginase retained the 85% of the initial activity after incubation at 90${\circ}$C for 30 min. A correlation between themostability and resistance to proteolysis of commercial asparaginase and purified asparaginase from Strepfomyces lincolnensis M-20 was investigated. Purified thermostable asparaginase was resistant to trypsin and chymotrypsin treatment, while the commercial asparaginase was not themostable and was susceptible to proteolytic treatment with trypsin and chymotrypsin.

• Microbiology and Biotechnology Letters
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• v.20 no.6
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• pp.681-686
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• 1992

In the conversion of D.L-2-amino-$\Delta^2$-thiazoline-4-carboxylic acid(D,L-ATC) to L-cysteine using Pseudomonas sp. CU6. the effects of surfactants on whole cells and the stabilities of cellfree enzyme solution and continuous reactor packed with immobilized whole cells were investigated. The enzymatic reaction was little accomplished by whole cells without adding surfactants, whereas it was well carried out with SDS or Triton X-loo comparable to the case using cell-free enzyme solution. Enzyme activity of the cell-free solution was lost by 50% after 7 hours of storage at $30^{\circ}C$, but not at all under an anaerobic condition by sparging nitrogen gas. On the other hand. effect of nitrogen gas did not appear in a continuous reactor using immobilized whole cells, and hydroxylamine, an inhibitor of L-cysteine desulfhydrase, lowered the enzyme stability.

• KSBB Journal
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• v.19 no.3
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• pp.192-199
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• 2004

In this work the production of glutathione (GSH) by yeast Saccharomyces cerevisiae and the monitoring of the process were studied. In shaking culture the production of GSH was high at initial pH value of 4 and at temperature of 30$^{\circ}C$. But when L-cysteine was added to the culture medium at the beginning of the cultivation, the productivity of GSH was low. In case 0,5% (v/v) of L-cysteine, glycine and glutamic acid were introduced to the culture medium in the exponential cell growth phase, high concentration of GSH (about 90 mg/L) was produced in the bioreactor. A fed-batch operation with stepwise glucose feeding strategy allowed to produce 102 mg/L of GSH. The cultivation processes were on-line monitored by a 2-dimensional fluorescence sensor. A few off-line data such as cell growth, cystein concentration, phosphate concentration and GSH productivity could be well correlated to the fluorescence intensity of some combinations of excitation and emission wavelengths.

• Journal of Plant Biotechnology
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• v.37 no.1
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• pp.77-83
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• 2010

Eighteen cultivars of tomato were tested for their regeneration response. Lycopersicon esculentum cv. 2001-58 showed a very high frequency of regeneration (93%). We evaluated the effect of two compounds with known antioxidant activity (ascorbic acid and cystein). The use of ascorbic acid ($200\;-\;300\;{\mu}M/L$) has a positive effect on shoot regeneration. To develope a system for plastid transformation in tomato via homologous recombination, we constructed the tomato plastid expression vector (pKRT22-AG) harboring 2.2 kb flanking sequences cloned from intact plastid genome and gfp gene. To investigate the factors affecting the delivery system of the pKRT22-AG into chloroplast using bombardment, We assessed the optimal DNA concentration, gold particle volume and target distance. Expression of the GFP protein was observed within chloroplast on protoplast of cotyledon explant by confocal laser scanning microscopy, which indicates that the protocol developed in this study be useful for the production of plastid transgenic plants in tomato.

• Food Science and Preservation
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• v.10 no.4
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• pp.527-533
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• 2003

This study was performed for increasing the consumption and developing the function of pumpkin(Cucurbita moschata DUCH.) seed. The changes of the contents of general chemical compositions, fatty acids, amino acids, ascorbic acid and ${\beta}$-carotene during sprouting were analyzed. Also, the bitter taste, which was produced during sprouting, were purified by using thin layer chromatography and preparative high pressure liquid chromatography. The purified bitter compound was identified by mass spectrum and nuclear magnetic resonance($^1$H '||'&'||' $\^$13/C-NMR). Weight of pumpkin seed sprout was increased to 348.4% and the length of stem was dramatically increased at 8 days. In each head and stem parts of the pumpkin seed sprout, the contents of protein and lipid were decreased, however, the contents of fiber, ash and soluble inorganic nitrogen were increased. The fatty acids of the pumpkin seed sprout were mainly represented as linoleic acid, oleic acid, palmitic acid and stearic acid. During sprouting, palmitic acid was gradually increased, reversely, linoleic acid was gradually decreased. The general amino acids of head part in the pumpkin seed sprout grown at 23$^{\circ}C$ during 8 days were orderly more contained glycine, alanine, arginine, cystein and proline. Those of free amino acids were orderly more contained arginine, threonine, alanine and glutamine. The contents of L-ascorbic acid and ${\beta}$-camtene of the pumpkin seed sprout were gradually increased with increasing sprouting days. The bitter taste material of head part of the pumpkin seed sprout was detected at Rf value 0.72 on silicagel TLC plate and separuted as one peak by HPLC. The chemical structure of the puified bitter compound was identified as a cucurbitacin glycoside by MS and NMR. The content of bitter compound at 8 days was contained 42.2 mg per 1kg sprout head.