• 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.

• Ocean and Polar Research
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• v.39 no.4
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• pp.269-277
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• 2017

Medium compositions for the hyperthermophilic archaeon, Thermococcus onnurineus NA1 was statistically optimized to enhance formate-driven hydrogen ($H_2$) production by using response surface methodology. From the Plackett-Burman design-based experiment, it was confirmed that among the minor components of medium such as KCl, $MgSO_4$, $NH_4Cl$, Cystein-HCl, trace elements, Fe-EDTA and $CaCl_2$, the trace elements were screened as the only positively effective components with respect to $H_2$ production. Subsequently, the optimal concentrations of the trace elements and the major components of a medium such as NaCl, yeast extract and sodium formate were determined from the five-level central composite design (CCD)-based experiment. The resulting quadratic model predicted the maximum $H_2$ production of 46.6 mmol/L in serum bottle and it was validated experimentally using the optimal medium initially supplemented with 26.70 g/L of NaCl, 9.81 g/L of sodium formate, 3.50 g/L of yeast extract and 4.59 mL/L of trace elements. From the duplicate batch cultivations in the fermentor using the optimized medium, the a maximum $H_2$ production rate up to 71.8 mmol/L/h could be obtained, which was a 65% enhanced value compared with that obtained using the control medium, showing the high efficiency of the optimized medium.

• Microbiology and Biotechnology Letters
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• v.30 no.2
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• pp.111-115
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• 2002

To produce yellow pigment selectively, mutants were induced from Monascus anka Nakazawa et Sato IFO 4478 (KCCM 11832 strain), and their characteristics were evaluated. Five kinds of auxotrophic mutants which required amino acids for growth and pigmentation, were isolated through a series of mutagenic treatments. Especially, asparagine auxotroph Y7 produced high ratio of yellow pigment. This mutant showed all the morphological characteristics of Monascuceae but the shape of colony and the diameter of conidia. Mutant Y7 was propagated by sexual reproduction more often than asexual reproduction, which could be effective in production of pigments. Yellow pigment produced extracellularly by the mutant Y7 was more soluble in polar solvents such as ethanol and water than in nonpolar solvents. Its productivity of yellow pigment was 2.2 times higher in the mutant Y7 than in parents. In addition, its yellow pigment showed characteristics of maximum absorption at 373 nm. Moreover, the hue of pigment produced by the mutant Y7 was bright yellow, and it was stable through the subculture over 10 generations.

• Food Science and Preservation
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• v.12 no.5
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• pp.489-495
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• 2005

Polyphenol oxidase (PPO) from Burdock (Arctium lappa L.) was purified and characterized. Purification of polyphenol oxidase was achieved by ammonium sulfate precipitation, Phenyl-sepharose CL-4B hydrophobic chromatography and Sephadex G-100 gel filtration chromatography. The molecular mass of the purified PPO was estimated to be 30 kDa by SDS polyacrylamide gel electrophoresis. In a substrate specificity, maximum activity was achieved with chlorogenic acid, followed by catechol and catechin. Whereas, there was low activity with hydroquinic acid, resorcinol or tyrosine. The optimum pH and temperature for enzyme activity were 7.0 and 35$\circC$ with catechol, respectively. The enzyme was most stable at pH 7.0 while unstable at acidic and alkaline pH. The enzyme was stable when heated to 40$\circC$. But heating at 50$\circC$ for more than 30 min caused 50% loss of activity. Ascorbic acid, L-cystein and $Cu^{2+}$ inhibited the activity of pholyphenol oxidase.

• BMB Reports
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• v.35 no.4
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• pp.432-436
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• 2002

Pseudomonas sp. S-47 is capable of degrading catechol and 4-chlorocatechol via the meta-cleavage pathway. XyITE products catalyze the dioxygenation of the aromatics. The sylT of the strain S-47 is located just upstream of the xylE gene. XylT of the strain S-47 is located just upstream of the xylE gene. XyIT is typical chloroplast-type ferredoxin, which is characterized by 4 cystein residues that are located at positions 41, 46, 49, and 81. The chloroplast-type ferredoxin of Pseudomonas sp. S-47 exhibited a 98% identity with that of P. putida mt-2(TOL plasmid) in the amino acid sequence, but only about a 40 to 60% identity with the corresponding enzymes from other organisms. We constructed two recombinant plasmids (pRES1 containing xylTE and pRES101 containing xylE without xylT) in order to examine the function of XyIT for the reactivation of the catechol 2,3-dioxygenase (XyIE) that is oxidized with hydrogen peroxide was recovered in the catechol 2,3-dioxygenase (C23O) activity about 4 mimutes after incubation, but the pRES101 showed no recovery. That means that the typical chloroplast-type ferredoxin (XyIT) of Pseudomonas sp. S-47 is involved in the reactivation of the oxidized C23O in the dioxygenolytic cleavage of aromatic compounds.

• The Korean Journal of Food And Nutrition
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• v.10 no.3
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• pp.382-386
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• 1997

In the present study, an attempt was made to investigate the effects of steeping treatment on browning of onion hydrolysate. After steeping treatment with solvents, phenols content of methanol and ethanol were showed 25.1mg/ml and 24.9mg/ml. And absorbance of methanol and ethanol was showed 0.26 and 0.22. L and b value of treatment with methanol and ethanol were lower than other solvents. Browning reaction of onion hydrolysate was decreased with increasing concentration of ethanol. Treatment of above 80% ethanol was effective to remove phenols and was showed a low color intensity. Treatment with 80% ethanol was more effective than addition of cystein to remove phenols and to decrease browing degree.

• Journal of Microbiology and Biotechnology
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• v.7 no.2
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• pp.127-131
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• 1997

Alkaline phosphatase (APase) was found to be inducible in Anabaena sp. strain CA Growth was less than control in presence of most amino acids except glycine and serine, but most amino acids enhanced APase activity. Highest APase activity was recorded in tyrosine supplemented culture followed by hydroxyproline, cystein, valine and glutamic acid. Threonine supplemented material showed lowest APase level (1.8 nmol/mg protein/min). Lactose, glucose, sodium pyruvate and succinate stimulated growth but not APase activity. APase activity was high in the presence of sucrose, mellibiose, mannitol, arabinose, maltose and sorbose, even though the growth in these supplements was less than in control. Organic phosphate sources supported good growth of the organism. Best growth occurred in presence of inorganic phosphate, adenosine diphosphate, fructose 1,6-diphosphate or ribulose 1,5-diphosphate, followed by other phosphorus sources tested. APase activity in presence of any of the organic phosphate sources was 3 to 5 fold low as compared to phosphate limited culture. Also, there was no APase activity in cultures grown on inorganic phosphate. These data indicate that most amino acids and a few carbohydrates (sucrose, mellibiose, arabinose and sorbose) are suitable for APase production. Lactose, glucose, pyruvate or succinate may be used as a carbon source during photoheterotrophic growth of the cyanobacterium. Glycine and serine are preferred nitrogen sources for its growth. Phosphate repressible APase activity has been found in Anabaena sp. strain CA.

• 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.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.3
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• pp.278-284
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• 1994

The sulfur amino acid composition in soybean (Glycine max L.) seeds may be an essential characteristic of new cultivars for some animal diets. Variation in seed storage protein among genotypes might make it possible to improve the quality of seed protein by genetically altering seed storage protein composition through plant breeding. This study was carried out to determine if mutant strains have potential for improving seed protein quality in soybean. Ten mutant strains had a distinct characteristic of seed storage protein subunits. Among the mutant strains, the sulfur amino acid compositions(methionine plus cystein) of Keburi(P.I.417016), Keburi(P.I.506817), and P.I.54608-1 were relatively higher than those of the others and were 1.9, 2.1, and 1.8%, repectively, which might be due to low levels of ${\alpha}$, ${\alpha}$', and ${\beta}$ subunits of 7S protein. Therefore, it is concluded that the mutant strains, Keburi(P.I.417016), Keburi(P.I.506817), and P.I.54608-1 appear to be potential materials for a breeding program for improving sulfur amino acid composition, and the others also seem to be possible breeding materials for other uses.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.3
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• pp.309-312
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• 2004

We performed exon trapping in order to locate functional genes on chicken chromosomes (GGA) and to identify functional gene sequences from chicken cosmids. Sequence analysis of 100 clones revealed 17 putative exons, five of which were identified with known sequences in a gene database search: thymopoietin beta (TMPO), U5 snRNP-specific 40 kDa protein (HPRP8BP), dihydropyridine receptor alpha 1 subunit (CACNL1A3), cystein string protein (CPS) and C15orf4. We attempted to map the genes to chicken chromosomes by using FISH and linkage analysis. The chromosomal localizations were GGA1 (TMPO), GGA10 (C15orf4), GGA23 (HPRP8BP) and GGA28 (CPS) by FISH and linkage analysis, while that of CACNL1A3 was predicted to be on a microchromosome by FISH but not by linkage analysis. Comparative mapping analyses between chickens and humans for the genes revealed both known and new synteny. The syntenic conservation between GGA1 and human chromosome (HSA) 12q23 (TMPO) and between GGA10 and HSA15q25 (C15orf4), were consistent with a recent publication, while two new syntenies were observed between GGA28 and HSA20q13.3 in CPS and between GGA23 and HSA1p34-35 in HPRP8BP. The information of presently mapped genes can contribute as anchor markers based on functional genes and the construction of a comparative map.