• Food Science and Industry
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• v.50 no.4
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• pp.24-49
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• 2017

Volatile flavor compounds of cheonggukjang and doenjang, which are the most representative Korean soybean fermented foods, were compiled throughout literature review. Total of 225 and 404 volatile flavor compounds were found in cheonggukjang and doenjang, respectively. The most characteristic volatile flavor compounds in cheonggukjang are thought to be pyrazine compounds. In addition, acids, such as 2-methyl propanoic acid, butanoic acid, 2-methyl butanoic acid, and 3-methyl butanoic acid, contribute to aroma characteristics of cheonggukjang. On the other hand, ester compounds are the most predominant volatile flavor compounds in doenjang. Ninety six ester compounds were detected in doenjang while 22 ester compounds were identified in cheonggukjang. Pyrazine compounds and acids also play an important role in the flavor of doenjang. Compilation of volatile flavor compounds from cheonggukjang and doenjang will provide basic information to food industry to understand and improve aroma characteristics of cheonggukjang and doenjang.

• Membrane Journal
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• v.10 no.4
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• pp.186-191
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• 2000

The recovery of three ethyl esters (aroma model compounds; ethyl acetate, ethyl propionate. ethyl butyrate) from aqueous solutions was studied for vapor permeation with surface-modified hydrophobic alumina membrane, Although the driving force of ethyl butyrate is the highest, the ethyl butyrate concentration in permeate is lower than those of propionate and acetate. Since the solubility of aroma compounds for water is very low, phase separation occurred in permeate, and we could obtain pure ethyl esters. The experimental results showed that the porous hydrophobic alumina membrane had high selectivity and permeation flux on the ester-model compounds.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.6
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• pp.654-659
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• 2002

To investigate the effects of preparation conditions of encapsulating ester compounds on retention rate of core material in microcapsules prepared with sea tangle alginate, the amounts of ester compounds migrated gelling solution (1 M $CaCl_2$) and washing water from microcapsules that were prepared by adding kinds of ester compound, by controlling ratios of emulsifier to ester compounds and by differing ratios of alginates (wall material) to ester compounds (core material) were measured. Also the amount of ester compounds retained in microcapsules was measured. The higher weight molecular of ester compounds were, the lower amounts of ester compounds migrated gelling solution and washing water from microcapsules were, But its amounts retained in microcapsules were increased, The changes of ethyl caprylate amount migrated gelling solution and washing water from microcapsules prepared by increasing ratios of emulsifier to ethyl caprylate were little, but its half-lives in microcapsules during storage at 25$^{\circ}C$ were steeply increased. Increasing ratios of wall material to core material, ethyl caprylate amount migrated gelling solution and washing water from microcapsules showed 1.8$\~$$2.0\%$ and 2.9$\~$$3.5\%$ respectively but half-lives of ethyl caprylate retained in alginate microcapsules were increased.

• Archives of Pharmacal Research
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• v.14 no.1
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• pp.48-51
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• 1991

Amides from amino acid ester and nalidixic acid were synthesized. The solubility characteristics and partition coefficient of the compounds were studied. The hydrolysis of the compounds was studied in the simulated gastric fluid and simulated intestinal fluid. Some compounds showed better antibacterial activity than nalidixic acid.

• Journal of the Korean Chemical Society
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• v.19 no.3
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• pp.169-173
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• 1975

Ten previously unreported dipeptides ontaining aminobenzylphosphonic acid were prepared by carbodiimide method. These are; Glycyl-dl-1-aminobenzylphosphonic acid, alanyl-dl-1-aminobenzylphosphonic acid, L-alanyl-dl-1-aminobenzylphosphonic acid, N-phthalyl-L-phenylalanyl-dl-1-aminobenzylphosphonic acid diethyl ester, N-carbobenzoxyglycyl-dl-1-aminobenzylphosphonic acid diethyl ester, N-carbobenzoxyalanyl-dl-1-aminobenzylphosphonic acid diethyl ester, N-carbobenzoxy-L-alanyl-dl-1-aminobenzylphosphonic acid diethyl ester, glycyl-dl-1-aminobenzylphosphonic acid diethyl ester hydrobromide, alanyl-dl-1-aminobenzylphosphonic acid diethyl ester hydrobromide and L-alanyl-dl-1-aminobenzylphosphonic acid diethyl ester hydrobromide. The first six compounds were characterized, and the last four compounds were obtained in the crude state.

• Fibers and Polymers
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• v.3 no.3
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• pp.91-96
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• 2002

Polyhydroxyamides derivatized with trifluorormethyl ether and trifluoromethyl ester groups were investigated as possible candidates for a new flame retardant polymer. Model compounds for these derivatized polyhydroxyamides were synthesized and their cyclization chemistry was investigated. The model compound study revealed that trifluorornethyl ester group containing model compounds can cyclize on heating, while trifluoromethyl ether group containing model compounds cannot. The non-fluorinated ether and ether derivatives behaved similarly. The trifluoromethyl ester derivatized polyhydroxyamides were synthesized according to the procedures for the model compounds. TGA characterization revealed that the fluorinated polymers have nearly same thermal stability as the underivatized PHA after cyclization.

• Journal of Applied Biological Chemistry
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• v.43 no.4
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• pp.264-268
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• 2000

High activity of acidic ethylacetate extract from the culture supernatant of ginseng growth-promoting bacterium Pseudomonas fluorescens KGPP 207 and its fractions were demonstrated through wheat coleoptile bioassay. The following auxins and auxin-like compounds were identified in these fractions by combined gas chromatography-mass spectrometry: indole-3-acetic acid, indole-3-acetic acid methyl and ethyl ester, indole-3-butyric acid, indole-3-lactic acid and its methyl ester, indole-3-propionic acid, indole-3-pyruvic acid, p-hydroxyphenyl acetic acid, p-hydroxyphenyl acetic acid methyl and ethyl ester, phenyl acetic acid and its methyl ester. The bacterium KGPP 207 belongs to the strain of P. fluorescens which produces plant growth regulators and its beneficial effect on the ginseng growth may be due to the formation of the identified compounds.

• Korean Journal of Environmental Agriculture
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• v.16 no.3
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• pp.269-273
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• 1997

This research aims at developing a new plant growth inhibitors related to abscisic acid by means of esterification of (S)-(+)-ABA with p-hydroxy methyl cinnamate and umbelliferone, and testing its biological activity on growth of rice seedlings. The over-all yield of ABA-methyl cinnamate(AC) and ABA-umbelliferone(AC) ester compounds were 83% and 78%, respectively. The growth inhibition activity of these synthetic compounds were shown about 3 to 10 times(AC) and 10 to 30 times(AU) higher than (S)-(+)-ABA.

• The Korean Journal of Food And Nutrition
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• v.12 no.4
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• pp.415-420
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• 1999

Petal of Azalea(Rhododendron mucronulatum Turcz) was incubated with Gokja at 3$0^{\circ}C$ for seven days and the essential oil components of petal of Azalea before and after incubated were analyzed using a GC/MSD. Ten or more essential oil components including n-heneicosane n-tricosane n-tetreacosane n-pentacosane n-heptacosane n-nonacosane and n-hentriacontane were identified from the petal of Azal-ea before incubated while oxygen-containng compounds including (E)-heptenal 2-ethoxy-1 -hexanol n-hexadecanoic acid methyl ester 9, 12-octadecadienoic acid methyl ester 9,12,15-octadecatrienoic acid methyl ester, n-octadecanoic acid methyl ester n-eicosanoic acid methyl ester and 9-docosaenoic acid methyl ester as well as n-alkanes such as n-tricosane that n-pentacosane were identified from the petal of Azalea after incubated. These results suggest that n-alkanes in petal of Azalea might be degraded and some oxygen-containing compounds such as aldehyde, esters and /or acids might be produced when pet-al of Azalea is incubated with Gokja.

• Applied Biological Chemistry
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• v.50 no.3
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• pp.233-237
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• 2007

The roots of Brassica campestris ssp rapa were extracted with 80% aqueous MeOH, and the concentrated extract was partitioned with EtOAc, n-BuOH and $H_{2}O$. From the EtOAc and n-BuOH fractions, five compounds were isolated through the repeated silica gel column chromatographies. From the result of spectroscopic data including NMR and MS, the chemical structures of the compounds were determined as palmitic acid methyl ester (1), linolenic acid methyl ester (2), linoleic acid methyl ester (3), ${\beta}-sitosterol$ (4) and daucosterol (5).