• Journal of the Korean Chemical Society
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• v.54 no.1
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• pp.55-58
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• 2010

Aliphatic and aromatic nitro compounds were selectively reduced to their corresponding amino derivatives in good yields using formic acid and CeY zeolite under monomode reactor. This system is found to be compatible with several sensitive functionalities. Beside the recycling result showed it had a long catalyst lifetime and could maintain activity even after being used for 20 cycles.

• Korean journal of applied entomology
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• v.34 no.1
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• pp.9-14
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• 1995

From a chemist's perspective, Scarabaeidae is one of the most exciting group of insects to work on the isolation, identification, and synthesis of sex pheromones because-as opposed to Lepidoptera, which by and large utilizes straight chain alcohols, aldehydes, and acetates-the pheromonal chemistry of scarab beetles is remarkably diverse. While species in the subfamily Rutelinae utilize pheromone constituents, which are presumably fatty acid derivatives, the more primitive species in the subfamily Melolonthinae use phenolic, amino acid derivative, and terpenoid compounds. Here, I discuss the recent advances we have accomplished in the identification of scarab sex pheromones with especial emphasis on their chemical diversity. Also, I discuss the potential role of these sex pheromones in insect pest management. Field tests revealed that, in contrast to what has been frequently observed in the Lepidoptera, the higher the dosage of sex pheromone loaded in the traps the greater the capture of scarab beetles. These data suggest that mass trapping is more likely to be useful for scarab pest management than mating distruption.

• Textile Coloration and Finishing
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• v.25 no.4
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• pp.247-253
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• 2013

The enzyme-like catalytic functions of metal complex phthalocyanine derivatives those containing carboxylic acid groups could be applied as odor-removing systems and antibacterial systems. Pyromellitic dianhydride and 4-nitrophthalimide were used as starting material for synthesizing dinitro-tetracarboxylic acid iron phthalocyanine(compound 1). Then diamino-tetracarboxylic phthalocyanine(compound 2) was obtained by reduction of compound 1. For the formation of covalent bond with cellulose fiber, cyanuric chloride was introduced to the amino group of compound 2 by condensation reaction compound 3. The exhaustion method was employed for adsorbing compound 3 on cotton fiber. K/S values of each fabrics were measured by a CCM system and deodorizing rates were tested by a detector tube method for ammonia gas. K/S values of treated cotton fiber with compound 3 were arranged from 2.1 to 4.2 at $90^{\circ}C$ of exhaustion temperature. Deodorizing rates provided result of 81%, 84%, 88%, 91%, by passing time of 30 min, 60 min, 90 min, 120 min, respectively.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.244.2-244.2
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• 2003

For the development of new synthetic method for unnatural amino acid esters, alkyl ${\alpha}$-anilinophenylacetates were synthesized through base-catalyzed hydrolysis of 1,5-diphenylhydantoins in methanol and O-alkylation of sodium ${\alpha}$-anilinophenylacetate with alkyl halides in DMF. Even though hydrolysis of hydantoin ring was undertaken under about 30-40$^{\circ}C$ in methanol, the hydantoic acid sodium salt was continuously converted to the sodium ${\alpha}$-anilinophenylacetate. (omitted)

• Journal of Food Hygiene and Safety
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• v.26 no.3
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• pp.242-247
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• 2011

A greening phenomenon has been observed in some plant foods such as chestnut, sweet potato, burdock, and others during processing. The formation of the pigments was postulated as reactions of primary amino compounds with chi orogenic acid or caffeic acid ester, yielding acridine derivatives. Acridine derivatives have been regarded as mutagenetic agents. For the reason, the bacterial reverse mutation test was carried out to evaluate the genotoxicity of green pigment using Salmonella typhimurium TA98 and TA100. Alanine, arginine, aspartic acid, glycine, lysine, and phenylalanine were reacted repectively with chlorogenic acid to synthesize model compound. Green pigment was extracted from sweet potato. Maximum concentration of 2 and 50 mg/plate was tested for the synthetic green pigments and extracted green pigment respectively, taking bacterial survival, solubility, and color intensity into consideration. There was no signigicant increase in the reverse mutation either with or without S9 activation system by any test material. Though further studies with other genotoxicity test system are necessary, both synthetic and sweet potato green pigments seemed not to cause mutation despite the acridine moiety in their structures.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.8
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• pp.1246-1250
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• 2005

This study was carried out to analyze the components of the stem of bush clover, Lespedeza bicolor to obtain basic data on the studies of the physiological function and a possibility of utilizing L. bicolor. General components of L. bicolor were 82.35$\%$ carbohydrate, 13.38$\%$ moisture, 2.80$\%$ crude protein, 0.86$\%$ crude ash and 0.61$\%$ crude fat. The content of reducing sugar was 147.58 mg/100 g. The total amount of free sugar was 52.4 mg/100 g that was composed of 31.0 mg/100 g fructose, 16.7 mg/100 g glucose and 4.7 mg/100 g sucrose. In the results of mineral analysis, the content of Ca was the highest (472.97 mg/100 g) and followed by 206.70mg/100 g of K. The total amount of hydrolyzed amino acid was 148.95 mg/100 g that consist of 31.74 mg/100g of essential amino acid and 117.24 mg/100 g of non-essential amino acid. Total free amino acids were contained 106.39 mg/100 g that was composed of 8.41 mg/100 g essential amino acids and 97.98 mg/100 g the non-essential, and proline (62.92 mg/100 g) was the highest that account for 59.8$\%$ of total free amino acids. Total content of amino acid derivatives was 30.01 mg/100g and that of $\gamma$ -aminoisobutyric acid was the highest as 12.57 mg/100 g among them.

• BMB Reports
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• v.40 no.2
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• pp.239-246
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• 2007

Riboflavin synthase from Escherichia coli is a homotrimer of 23.4 kDa subunits and catalyzes the formation of one molecule each of riboflavin and 5-amino-6-ribitylamino- 2,4(1H,3H)-pyrimidinedione by the transfer of a 4-carbon moiety between two molecules of the substrate, 6,7- dimethyl-8-ribityllumazine. Each subunit comprises two closely similar folding domains. Recombinant expression of the N-terminal domain is known to provide a $C_2$-symmetric homodimer. In this study, the binding properties of wild type as well as two mutated proteins of N-terminal domain of riboflavin synthase with various ligands were tested. The replacement of the amino acid residue A43, located in the second shell of riboflavin synthase active center, in the recombinant N-terminal domain dimer reduces the affinity for 6,7-dimethyl-8-ribityllumazine. The mutation of the amino acid residue C48 forming part of activity cavity of the enzyme causes significant $^{19}F$ NMR chemical shift modulation of trifluoromethyl derivatives of 6,7-dimethyl-8-ribityllumazine in complex with the protein, while substitution of A43 results in smaller chemical shift changes.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.7 no.2
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• pp.147-152
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• 2021

C-11 Radiolabeled amino acid-based radiopharmaceuticals such as [¹¹C]MET for brain tumor PET imaging have limitations due to their short half-life (20 min). F-18 radiolabeled amino acid derivatives have been developed to overcome for the short half-life, one of which is [¹⁸F]FET. Brain tumor imaging using [¹⁸F]FET showed high uptake in tumor region and no non-specific uptake in inflammatory tissue, which was useful in discriminating the difference between inflammation and tumor especially. In this study, [¹⁸F]FET was synthesized using an automatic synthesis module and quality tests were carried out including enantiomeric purity analysis with reference compounds. Radiochemical yield was 50.3 ± 4.9% (n=7, decay-corrected) with molar activity of 76 ± 17 GBq/mmol. The radiochemical purity of >99%. Enantiomeric purity of [¹⁸F]FET using chiral HPLC analysis showed >99%, which was confirmed by co-injection with the L-FET and D-FET authentic standards. [¹⁸F]FET was prepared with high radiochemical yield and molar activity including no racemate mixture.

• Archives of Pharmacal Research
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• v.20 no.5
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• pp.454-458
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• 1997

Two human liver UDP-glucuronosyltransferase cDNA clones, HLUG25 and UDPGTh2 were previously shown to encode isozymes active in the glucuronidation of hyodeoxycholic acid (HDCA) and certain estrogen derivatives (e.g., estriol and 3,4-catechol estrogens), respectively. in this study we have found that the UDPGTh2-encoded isoform (UDPGTh2) and HLUG25-encoded isoform (UDPGThl) have parallel aglycone specificities. When expressed in COS 1 cells, each isoform metabolized three types of dihydroxy- or trihydroxy-substituted ring structures, including the 3,4-catechol estrogen (4-hydroxyestrone), estriol, 17-epiestriol, and HDCA, but the UDPGTh2 isozyme was 100-fold more efficient than UDPGTh1. UDPGTh1 and UDPGTh2 were 86% identical overall (76 differences out of 528 amino acids), including 55 differences in the first 300 amino acids of the amino terminus, a domain which conferred the substrate specificity. The data indicated that a high level of conservation in the amino terminus was not required for the preservation of substrate selectivity. Analysis of glucuronidation activity encoded by UDPGTh1/UDPGTh2 chimeric cDNA constructed at their common restriction sites, Sac I (codon 297), Nco I (codon 385), and Hha I (codon 469), showed that nine amino acids between residues 385 and 469 were important for catalytic efficiency, suggesting that this region represented a domain which was critical for the catalysis but distinct from that responsible for aglycone-selection. These data indicate that UDPGTh2 is a primary isoform responsible for the detoxification of the bile salt intermediate as well as the active estrogen intermediates.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.5
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• pp.816-828
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• 1995

During the industrial preparation and the storage of foods, the side chain of some protein-bound amino acids can react chemically each other or with other molecules present in the food. The following reactions have been described : destruction of amino acids, racemization, protein-protein interactions, reactions of proteins with reducing sugars, oxidizing agents, or polyphenols. Apart from total destruction, the main reacitons are the forming of Maillard reactions products(e.g. fructoselysine) and the crosslinking with other amino acids in the same or in another protein molecule(e.g. lysinoalanine). The most often involved amino acid is lysine because of its free functional ${\varepsilon}-amino$ acid group. Generally derivatives of amino acids or crosslinks in polypeptides influence the bioavailability and the overall digestibility of the protein. This work reviews the technological, analytical, nutritional, and physiological problems related to the formation of fructoselysine and lysinolalnine in human foods, and evaluates the possible health risk for humans. A summary of the available information is of help in considering whether or not the presence of fructoselysine/lysinoalanine in foods represents a danger to man. The reduction in protein quality through these reactions is not a problem for the general population, but it is extremely important in infant foods, since infants are often nourished with a limited number of food product(e.g. formular foods) which are sensitive to the Mailard reaction.