• Korean Journal of Food Science and Technology
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• v.51 no.4
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• pp.324-329
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• 2019

Volatile flavor compounds of radish fermented by lactic acid bacteria were extracted using solid-phase microextraction (SPME) and analyzed by gas chromatography-mass spectrometry (GC-MS). A total of 45 volatile flavor compounds were identified. The volatile flavor compounds in unfermented radish mostly consisted of sulfur-containing compounds (95.85%) and aldehydes (2.61%). While the composition ratio of volatile flavor compounds in radish fermented for two days changed to sulfur-containing compounds (75.53%) and acids (11.12%). As the fermentation period was increased, the contents of dimethyl disulfide, dimethyl trisulfide, diallyl sulfide, diallyl disulfide, and diallyl trisulfide, which have unique garlic and scallion flavor, decreased, and acetic acid and 1-hexanol, which have a sour and fruity flavor, increased. These changes in volatile flavor compounds seemed to have affected the flavor characteristics of fermented radish.

• Preventive Nutrition and Food Science
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• v.13 no.1
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• pp.18-22
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• 2008

Volatile components in field bean (Dolichos lablab) were collected by simultaneous steam distillation and solvent extraction and analyzed by gas chromatography-mass spectrometry. One hundred and five components were identified including alcohols (32), ketones (18), aldehydes (9), acid (1), alkanes (5), aromatics compounds (4), esters (2), furans (2), naphthalene (1), pyrazines (4), pyridine (3), sulfur-containing compounds (4) and terpenes (7) and miscellaneous compounds (13). Relatively high concentration of n-hexanal found in the field bean might be undesirable to some consumers.

• Journal of Dairy Science and Biotechnology
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• v.25 no.1
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• pp.33-36
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• 2007

Catabolism of amino acids, including sulfur-containing amino acids, can be responsible for the development of cheese flavor during ripening Since accelerating, intensifying, modulating cheese flavor development is of major economical interests, the identification of flavor compounds and enzymes contributing to cheese flavor development needs to be investigated. Generally, two different pathways, which are a transamination pathway catalyzed by aminotransferases and an elimination reaction catalyzed by lyases, potentially lead to conversion of amino acids into flavor compounds. In this review, enzymes and amino acid catabolic pathways responsible for cheese flavor formation will be discussed.

• Archives of Pharmacal Research
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• v.22 no.6
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• pp.559-564
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• 1999

In order to discover new cancer chemopreventive agents from natural or synthetic products, a structurally diverse class of chemopreventive agents was evaluated using in vitro biomarker of inhibition of 12-O-tetradecanoylphorbol 13-acetate (TPA)-induced ornithine decarboxylase (ODC) activity in cultured mouse epidermal 308 (ME)308 cells. As a results, apigenin, benzylisothiocyanate, curcumin, diallyl disulfide, N-(4-hydroxyphenyl)retinamide (4-HPR), menadione, miconazole, nordihydroguaiaretic acid (NDGA) and phenethyl isothiocyanate showed potent inhibitory effects in this process. A chemically diverse group of compounds was included in the evaluation, such as flavonoids, retinoids, isothiocyanates, sulfur-containing compounds and phenolic antioxidant compounds. These data are suggestive to understand the cancer chemopreventive potential mediated by these substances.

• Bulletin of the Korean Chemical Society
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• v.10 no.1
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• pp.75-80
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• 1989

The approximate rates and stoichiometry of the reaction of excess potassium 9-sec-amyl-9-boratabicylco[3.3.1]nonane (K 9-sec-Am-9-BBNH) with selected organic compounds containing representative functional goups under standardized conditions (tetrahydrofuran, $0^{\circ}C)$ were examined in order to explore the reducing characteristics of the reagent for selective reductions. The reagent readily reduces aldehydes, ketones, acid chlorides and epoxides to the corresponding alcohols. However, carboxylic acid, aliphatic nitriles, t-amides, and some sulfur compounds show very little reactivity or no reactivity to this reagent. The most interesting feature of the reagent is that aromatic nitriles are reduced moderately to the corresponding aldehyde stage, wheras aliphatic nitriles are inert. In addition, the reagent shows a high stereoselectivity toward cyclic ketones at $0^{\circ}C$ and - $25^{\circ}C.$ The selectivity exhibited at $0^{\circ}C$ is comparable to that by lithium trisiamylborohydride at that temperature.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2003.05a
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• pp.527-531
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• 2003

석탄가스화 생성물에서 발생하는 미량의 유황가스를 정제하기 위해서는 먼저 석탄가스화에서 발생하는 미량의 유황가스의 분석이 필요하다. 이러한 초미량 분석을 위한 기기들은 현재 시중에서 너무나 고가로 판매되고 있기에 본 연구에서는 비교적 저렴하고 절차가 간단한 분석방법을 개발키로 한 동기가 부여되었다.(중략)

• 한국기계연구소 소보
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• s.13
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• pp.15-25
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• 1984

The infrared spectra were determined to discover the characteristics and properties of poff-, PV-, and cc-samples, and studied influence on the formation of mesophase or liquid crystal. The experimental results were as follows; a) Samples with long aliphatic side chain appear cracking texture on temperature forming liquid crystal. b) The fine isotropic microstructure appears in a heterogeneous material containing sulfur, 7.18 w%. c) In the size of molecular weight the lighter than 500 form liquid crystal. d) When poff-sample was treated at $400^{\circ}C$ aliphatic hydrocabon compounds decrease, presented well-oriented bulk liquid crystal.

• YAKHAK HOEJI
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• v.28 no.1
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• pp.25-27
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• 1984

Some $\betha$-lactam antibiotics-penicillins and cephalosporins-were determined by gas chromatography (GC) with flame photometric detector (FPD) which was selective and sensitive to sulfur-containing compounds. Methyl ester derivatives of carboxyl group in $\betha$-lactam antibiotics were prepared using 0.5Mmethyl iodide in methylene chloride and were taken for gas chromatography with 0.9% or 0.6% QF-1 on Chromosorb WAW-DMCS. We have found that it is possible to determine methyl esters of $\betha$-lactam antibiotics by GC/FPD.

• Food Science and Biotechnology
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• v.18 no.6
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• pp.1447-1458
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• 2009

Volatile extracts obtained from traditional Chinese-type soy sauces prepared with soybean (SSSB) and defatted soy meal (SSDSM) by solid phase microextraction (SPME) and direct solvent extraction (DSE) were analyzed by gas chromatography-mass spectrometry (GC-MS). The volatile flavor compounds and relative contents of different chemical classes detected in SSSB and SSDSM were compared for their differences. Results showed that significant differences in both constituents of volatile flavor compounds and relative contents of different chemical classes were observed for both kinds of soy sauces. A total of 152 and 131 compounds were identified in SSSB and SSDSM, respectively, and 102 volatile flavor compounds were common in both kinds of soy sauces. Moreover, relative contents of acids, aldehydes, esters, furan(one)s, miscellaneous compounds, phenols, pyrazines, pyrrol(idinon)es, and sulfur-containing compounds in both kinds of soy sauces were all significantly different.

• Journal of the Korean Society of Industry Convergence
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• v.26 no.3
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• pp.371-380
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• 2023

This study aimed to present data for the industrialization of Omija added onion fermented beverage (OOFB) development by analyzing the volatile flavor components. A total of 55 compounds, including 4 terpene derivatives, 9 esters, 5 aromatic compounds, 6 alcohols, 7 ketones, 3 aldehydes, 11 acids, 1 sulfur-containing compound, 8 furans and 1 other, were identified in OOFB. The content of fragrance components was high with 37.8% of acids and 29.0% of furans. 2,5-dimethyl thiophene, a sulfur compound, is a compound produced during the acetic acid fermentation of onion, and is thought to affect the onion flavor of OOFB.