• Proceedings of the PSK Conference
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• 2002.10a
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• pp.399.1-399.1
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• 2002

The chiral stationary phase derived from (＋) (18-crown-6)-2.3, 11.12-tetracarboxylic acid (18-C-6- TA) as a chiral selector has been employed for resolution of several $\alpha$-amino acids in HPLC. In a quest for the origin of chiral recognition of $\alpha$-amino acids in the presence of 18-C-6- T, A, as a chiral selector, these interactions responsible for the differential affinities shown toward enantioners were investigated by NNR spectroscopy. (omitted)

• Bulletin of the Korean Chemical Society
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• v.30 no.1
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• pp.163-171
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• 2009

Few $\alpha$-Hydroxy-$\beta$-amino acids were synthesized via various nucleophilic addition of the epoxide and followed by stereoselective nucleophilic substitution reaction and eliminative cleavage of the acetal selectively in diacetal compound. One of the synthesized $\alpha$-Hydroxy-$\beta$-amino acid reacted with L-leucine methylester to give corresponding dipeptide in good yields.

• Bulletin of the Korean Chemical Society
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• v.25 no.3
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• pp.347-348
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• 2004

• Bulletin of the Korean Chemical Society
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• v.26 no.6
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• pp.998-1000
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• 2005

• Archives of Pharmacal Research
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• v.16 no.3
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• pp.180-185
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• 1993

The acid dissociation constants of certain Schiff bases derived from isatin with p-substituted benzoyl hydrazines and somee amino acids of glycine, $\beta$-and $\alpha$-alanine, valine, $\beta$-phenyl-$\alpha$-alanine and anthranilic acid have been detemined potentiometrically at different temperatures in different aquo-organic solvent mixtures (ethnol, dioxane, dimethyl formamide, methanol, acetone and tetrahydrofurance). The pKa values were demonstrated on the light of the different electornic and steric effects of the substituents and the sovlent characteristics. In all the mixed media used, ionization of the compounds decreased by increasing the mole fraction of the organic cosolvent. Theemodynamic parameters $(\Delta{H}^\circ,\;\Delta{G}^\circ,\;\Delta{S}^\circ)$ were evaluated. The structural effects of the investigated compounds on these parameters were reported and discussed.

• BMB Reports
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• v.31 no.1
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• pp.37-43
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• 1998

The catabolic ${\alpha}$-acetolactate synthase was purified to homogeneity from Serratia marcescens ATCC 25419 using ammonium sulfate fractionation, DEAE-Sepharose, Phenyl-Sepharose, and Hydroxylapatite column chromatography. The native molecular weight of the enzyme was approximately 150 kDa and composed of two identical subunits with molecular weights of 64 kDa each. The N-terminal amino acid sequence of the enzyme was determined to be Ala-Gln-Glu-Lys-Thr-Gly-Asn-Asp-Trp-Gln-His-Gly-Ala-Asp-Leu-Val-Val-Lys-Asn-Leu. It was not inhibited by the branched chain amino acids and sulfometuron methyl herbicide. The optimum pH of the enzyme was around pH 5.5 and the pI value was 6.1. The catabolic ${\alpha}$-acetolactate synthase showed weak immunological relationships with recombinant tobacco ALS, barley ALS, and the valine-sensitive ALS isozyme from Serratia marcescens.

• Bulletin of the Korean Chemical Society
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• v.23 no.7
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• pp.931-932
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• 2002

• Proceedings of the PSK Conference
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• 2001.10a
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• pp.229.3-230
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• 2001

• Journal of Life Science
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• v.10 no.1
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• pp.68-73
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• 2000

In order to develop new materials for the functional food, the components of safflower(Carthamus tinctorius L.) sprout was studied. Chemical composition, minerals, amino acids, and fatty acids of the leaf and the stem parts of 2 weeks grown safflower sprout were analyzed. The chemical composition of safflower spout was 12.7% (w/w) moisture, 28.5% crude protein, 10.1% crude fat, and 5.3% crude ash. Mineral contents of the leaf part were P 49%, K 22%, Mg 15%, Ca 10% whereas these of the stem part were K 51%, P 27%, S 10%, Ca 7%, Mg 4%. Other mineral contents were less than 2% in both parts. Especially, Pt was 0.18 ppb and 0.17 ppb in the leaf and the stem parts, respectively. The composition of the amino acid were approximately as follow, the major amino acid in the leaf and the stem were aspartic acid and glutamic acid, the contents of these were 10.7mg/g, 10mg/g in the leaf, 11.3 mg/g, 8.4 mg/g in the stem, respectively. The major fatty acids in the leaf and the stem parts were linoleic acid and $\alpha$-linolenic acid. The linoleic acid (C18:2) in the leaf and the stem parts were 67% (w/w) and 47% whereas the $\alpha$-linolenic acid. The linoleic acid (C18:2) in those parts were 14% (w/w) and 11%, respectively. On the basis of chemical analysis, the safflower sprout showed to have relatively high contents of crude protein and crude fat, minerals including small amount of Pt, polyunsaturated fatty acid as linoleic acid and $\alpha$ -linolenic acid. These results suggested that safflower sprout was found to be a useful material of natural health food for the functional food development.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.5
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• pp.464-468
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• 2015

Our government has performed to support the nation-wide application of customized fertilizer based on soil-testing results and crop nutrient balance in order to promote the environment-friendly agriculture and to respond the global environment guide-line since 2010. This study was performed at the selected local paddy fields (Hwaseong-si, Uiseong-gun and Miryang-si) with different soil chemical properties in 2012. The contents of amino acids measured showed an increasing trend with fertilization, and glutamic acid was the most abundant amino acid followed by aspartic acid, leucine and alanine. However, valine, isoleusine, tyrosine and lysine were not significantly affected by fertilization. The significant differences in grain N, expressed as a crude protein, and amino acids dose was observed between experimental sites (p<0.001), treatments (p<0.01 to 0.001) and interaction of both factors (p<0.01 to 0.001). In our experiment the following order of carbon skeleton backbones to produce amino acids was observed irrespective of experiment sites and fertilization: ${\alpha}$-ketoglutarate > oxalate > pyruvate > 3-phosphoglycerate > phosphoenolpyruvate. In conclusion, customized fertilizer had no difference in amino acids compared to the conventional-NPK practice which was higher than in no fertilization, and also the normal paddy represented slightly higher amino acids compared to the reclaimed. Further study based on the present results is required to investigate what is main factor to amino acids between genetic and environmental factors.