• YAKHAK HOEJI
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• v.33 no.2
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• pp.129-139
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• 1989

New diamide chiral stationary phases of four systematically substituted optically active N-(N-benzoyl-L-amino acid)-anilide synthesized from L-valine, L-leucine, L-isoleucine, and L-phenylalanine were described. The behaviors of these diamides as optically active stationary phases for the separation of N-trifluoroacetyl-D,L-amino acids were examined with respect to separation factors(${\alpha}$) and thermodynamic properties of interaction. The separation of twelve N-trifluoroacetyl-D,L-amino acid isopropyl esters were improved by the order of N-(N-benzoyl-L-leucyl)-anilide>N-(N-benzoyl-L-isoleucyl)-anilide>N-(N-benzoyl-L-valyl)-anilide>N-(N-benzoyl-L-phenylalanyl)-anilide. Eight amino acid derivatives with non-polar R-group and threonine, serine, aspartic acid, and glutamic acid enantiomers were separated on N-(N-benzoyl-L-leucyl)-anilide as chiral stationary phase with good separation factor between 1.07-1.25. The separation factors decreased with respect to increasing column temperature. Possible working temperature of diamide phase was between $130-190^{\circ}C$ for N-(N-benzoyl-L-phenylalanyl)-anilide and $130-180^{\circ}C$ for other three diamide phases. The differential Gibb's free energy (${\Delta}{\Delta}G$) of enantiomers was in the range of -100--180 cal/mol for ten amino acids and -40--60 cal/mol for alanine and aspartic acid.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.20 no.6
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• pp.520-528
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• 1987

Quality stability of roasted lavers during heat treatment and storage was investigated measuring the changes in pigments including chlorophyll a, carotenoids and biliproteins, fatty acids and free amino acids as the major quality factors. In roasting of fried lavers, carotenoids were found to lie more stable than chlorophyll a, and biliproteins were most heat labile. The overall heat stability of the pigments depended upon heating time and temperature. Chlorophyll a and carotenoids were retained more than $90\%$ in the casts of roasting for 90 min. at $60^{\circ}C;\;60min.\;at\;80^{\circ}C;\;10\;min.\;at\;100^{\circ}C;\;or\;5min.\;at\;150^{\circ}C$ while biliproteins remained about $70\%$. The lipids of dried lavers including polyunsaturated fatty acids appeared rather heat stable when compared to the stability of pigments under the same conditions of roasting. Spray of sesame oil or seasoning solutions on the surface of lavers after roasting seemed desirable for stabilizing pigments and free amino acids during storage particularly at low water activity. And that was also benefit for the protection of polyenoic fatty acids from rapid progress of oxidation during storage. Free amino acids were reduced fast during roasting, especially most of threonine and glycine while glutamic acid was rapidly lost during the storage.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.4
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• pp.556-562
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• 1995

The $\alpha$-amylase inhibitor from naked barley was purified by DEAE-cellulose, Concanavalin-A sepharose and superose 6 column chromatography, and confirmed by capillary electrophoresis. The purified $\alpha$-amylase inhibitor showed a single band of 29KD in molecular weight when estimated by the SDS-PAGE. Its purity was increased by 12-fold as compared to its crude extract, and its specific activity was found to be 336.7units/mg. The major amino acids of the $\alpha$-amylase inhibitor from naked barley was appeared to be glutamic acid, asparitic acid and arginine. The inhibitor from naked barley was glycoproteins and carbohydrate content of inhibitor was 1.0%.

• Proceedings of the Korean Biophysical Society Conference
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• 2002.06b
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• pp.32-32
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• 2002

To understand the functional roles of the neuron-specific $\beta$-subunit of large-conductance calcium-activated potassium ($BK_{Ca}$) channel, we isolate the full-length complementary DNA of $\beta$4-subunit from rat brain library and investigated its effects on the function of $\alpha$-subunit (Slo). The deduced amino acid sequence of rat $\beta$4 (r$\beta$4), 210 amino acids in length, was closely related to those of $\beta$4 subunits in other mammalian species but showed only a limited sequence homology to the other $\beta$-subunits, $\beta$1 to $\beta$3.(omitted)d)

• Bulletin of the Korean Chemical Society
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• v.33 no.6
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• pp.1873-1878
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• 2012

Polyamides have great potentials for diverse applications and the present production of their monomers mostly relies on resources from fossil fuel. Starting from undecylenic acid, a natural resource, we have developed both divergent and efficient processes for $C_{10}$, $C_{11}$ and $C_{12}$ ${\omega}$-amino acid and ${\alpha},{\omega}$-dicarboxylic acid monomers of the polyamides.

• Korean journal of food and cookery science
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• v.20 no.2
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• pp.164-169
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• 2004

The purpose of this study was to evaluate sensory characteristics, and to investigate nutrients and taste compounds in sauce made with shrimp or crab. Shrimp sauce fumed out to have better appearance, color, flavor and texture, and the taste of crab sauce was more excellent. In three kinds of shrimp sauces made with different thickeners, sauces used with rice and roux were evaluated to have a good taste and flavor. The major amino acids were -aminobutyric acid, alanine, ${\alpha}$-aminoadipic acid and citruline in shrimp sauce, and taurine, alanine, ${\alpha}$-aminoadipic acid and citruline in crab sauce. The major fatty acids of both samples were palmitic acid and oleic acid, and also palmitoleic acid and linoleic acid were much detected in shrimp and crab sauce. The content of crude protein was 1.62∼2.44%, and that of crude lipid was 0.92∼1.52% in the two sauces. The major minerals were potassium and sodium in shrimp and crab sauce.

• The Korean Journal of Food And Nutrition
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• v.10 no.4
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• pp.475-479
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• 1997

The effects of amino acids and metabolites in growth media on the biosynthesis of prodigiosin from Serratia marcescens ATCC 25419 were examined. The prodigiosin synthesis was decreased approximately by 50 to 80% by several amino acids and metabolites tested. The prodigiosin synthesis was increased approximately by 20 to 40% by a low concentration of glyoxylate(1 to 3mM) and outstandingly increased by 122% at 5mM concentration under anaerobic condition. However, the prodigiosin synthesis was decreased approximately by 50 to 90% at a high concentration(20 to 30mM) under anaerobic condition. The prodigiosin was not synthesized by pyruvate and $\alpha$-ketobutyrate under aerobic and anaerobic condition, with addition to glyoxylate under aerobic condition, among the range from 0.5 to 30mM, while the cell growth under anaerobic condition was decreased distinctly by a high concentration(20mM above) of glyoxylate. These data suggest that the growth and prodigiosin of S. marcescens is positively regulated by a low concentration of glyoxylate (1-5mM), but repressed by a high concentration of glyoxylate(20mM above) unlike pyruvate and $\alpha$-ketobutyrate.

• The Korean Journal of Food And Nutrition
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• v.9 no.4
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• pp.372-378
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• 1996

The effects of branched chain amino acids and metabolites in growth media on the biosynthesis of Serratia marcescens threonine dehydratase activity were examined. The enzyme activity was decreased above 60% by leucine among the range from 1 to 20 mM, and the enzyme activity was decreased approximately 20% by a low concentration of valine (1 to 4 mM), but not affected at high concentration (20 mM). However, the enzyme activity was increased approximately 100 to 140% by a low concentration of isoleucine (1 to 4 mM), but decreased approximately 25 to 80% at high concentration (15 to 30 mM). The enzyme activity was decreased by 25 and 58% by the simultaneous addition of all three branched chain amino acids at 2 and 10 mM concentration, respectively, but increased by 75 and 50% by the combination addition of isoleucine plus valine and isoleucine plus leucine at 2 mM, respectively. cAMP was decreased the enzyme activity approximately 10 to 40% by a low concentration (1 to 2 mM), but increased by 80% at high concentration (10 mM). These data suggest that S. marcescens threonine dehydratase should be multivalently repressed by branched chain amino acids, but positively regulated by a low isoleucine concentration and may play a regulatory role in an isoleucine biosynthetic pathway unlike the E. coli K-12 enzyme.

• Journal of Food Hygiene and Safety
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• v.33 no.6
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• pp.500-509
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• 2018

The objective of this study was to investigate the worth of extract husk and cobs of the Seakso 1 (EHCS) for the functional foods. We aimed to investigate the proximate composition, fatty acids, amino acids, antioxidant active substance contents, antioxidant activity, inhibitory activity of the ${\alpha}-amylase$ and ${\alpha}-glucosidase$. The proximate composition of the EHCS have represented 6.90% moisture, 7.31% crude ash, 0.52% crude fat and 7.07% crude protein. Among the 17 kinds of amino acids that were analyzed in thd EHCS, the glutamic acid was the highest, with 736.08 mg / 100 g. The fatty acids detected in the EHCS were palmitic acid oleic acid and linoleic acid. The proportion of the unsaturated fatty acids was 83.33%. We determined the contents of the antioxidant active substance by the total polyphenol and flavonoid. The total polyphenol and flavonoid contents were 99.87 mg/g and 25.02 mg/g, respectively. The antioxidative activity of the EHCS were determined using a DPPH and ABTS assay. In the antioxidative activity determination, the DPPH and ABTS radical scavenging activities were 95.62% ($1,000{\mu}g/mL$) and 92.00% ($10,000{\mu}g/mL$), respectively. The inhibitory activity of ${\alpha}-amylase$ and ${\alpha}-glucosidase$ (10 mg/mL) were 95.86% and 76.92%, respectively. These results suggest that the EHCS could be potentially used as a resource for the bioactive materials for health functional foods.

• Journal of Microbiology and Biotechnology
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• v.24 no.2
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• pp.236-244
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• 2014

The gene encoding ${\alpha}-\small{L}$-arabinofuranosidase (AFase) from Paenibacillus sp. DG-22 was cloned, sequenced, and expressed in Escherichia coli. The AFase gene (abfA) comprises a 1,509 bp open reading frame encoding 502 amino acids with a molecular mass of 56,520 daltons. The deduced amino acid sequence of the gene shows that AbfA is an enzyme consisting of only a catalytic domain, and that the enzyme has significant similarity to AFases classified into the family 51 of the glycosyl hydrolases. abfA was subcloned into the pQE60 expression vector to fuse it with a six-histidine tag and the recombinant AFase (rAbfA) was purified to homogeneity. The specific activity of the recombinant enzyme was 96.7 U/mg protein. Determination of the apparent molecular mass by gel-filtration chromatography indicated that AbfA has a tetrameric structure. The optimal pH and temperature of the enzyme were 6.0 and $60^{\circ}C$, respectively. The enzyme activity was completely inhibited by 1 mM $HgCl_2$. rAbfA was active only towards p-nitrophephenyl ${\alpha}-\small{L}$-arabinofuranoside and exhibited $K_m$ and $V_{max}$ values of 3.5 mM and 306.1 U/mg, respectively. rAbfA showed a synergistic effect in combination with endoxylanase on the degradation of oat spelt xylan and wheat arabinoxylan.