• Korean Journal of Food Science and Technology
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• v.22 no.4
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• pp.405-410
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• 1990

The aroma components of duchung tea and persimmon leaf tea were collected simultaneous distillation and extraction method. Those were analyzed and identified by GC-MS using a fused sillica capillary column. Seventy seven components, including 17 alcohols, 3 hydrocarbons, 15 ketones, 16 aldehydes, 8 esters,8 acids, 8 heterocyclic compounds and 2 phenols were confirmed in duchung tea. Seventy one components, including 17 alcohols, 10 hydrocabrons, 11 ketones, 13 aldehydes, 8 esters, 6 acids, 5 heterocyclic compounds and 1 phenol were confirmed in persimmon leaf tea. The most abundant components of duchung tea were aldehydes(23.31%) including 2-pentenal and heterocyclic compounds(16.71%) including $epoxy-{\beta}-ionone$. The most abundant components of persimmon leaf tea were alcohols(25.57%) including linalool and aldehydes(19.45%) including hexanal and hydrocarbons(10.40%) including ${\alpha}-copaene$.

• Journal of Photoscience
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• v.10 no.1
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• pp.9-20
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• 2003

Recent studies on the photoreactivity of l,4-unsaturated systems have changed some ideas that were firmly established in this area of research for many years. Thus, we have described the first examples of 2-aza-di-$\pi$-methane (2-ADPM) rearrangements promoted by triplet-sensitization and by single electron transfer (SET) using electron-acceptor sensitizers. These reactions afford N-vinylaziridine and cyclopropylimine photoproducts in the first examples of di-$\pi$-methane processes that yield three-membered ring heterocycles. l-Aza-1,4-dienes also undergo SET-promoted l-aza-di-$\pi$-methane (l-ADPM) rearrangements via radical-cation intermediates using electron acceptor sensitizers. In some cases, alternative cyclizations yielding different carbocycles and heterocycles have been observed. The l-ADPM and di-$\pi$-methane (DPM) reactions also occur via radical-anion intermediates on irradiation using electron donor sensitizers. On the other hand, the photoreactivity reported for $\beta$,${\gamma}$-unsaturated aldehydes for many years was decarbonylation to the corresponding alkenes. However, our studies demonstrate that these compounds undergo the oxa-di-$\pi$-methane (ODPM) rearrangement with high chemical and quantum efficiency. A comparison of the photochemical reactivity of $\beta$,${\gamma}$-unsaturated aldehydes and corresponding methyl ketones has shown that the ketones do not undergo the ODPM rearrangement while the corresponding aldehydes are reactive by this pathway. Monosubstituted $\beta$,${\gamma}$-unsaturated aldehydes at C-2 undergo the ODPM rearrangement yielding the corresponding cyclopropane carbaldehydes diastereoselectively. Finally, we have described the first examples of reactions, similar to the well know Norrish Type I process, which take place in the triplet excited state of $\beta$,${\gamma}$-unsaturated carbonyl compounds by excitation of the C-C double bond instead of the carbonyl group.

• The Korean Journal of Food And Nutrition
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• v.11 no.3
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• pp.272-277
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• 1998

We carried out separation and guantitation of flavor components by GC about essential oils extracted from deodorized corn oil at the different deodorizing temperature. Flavor components were detected total 16 kinds included aldehydes of 8 kinds, major components were propane, pentane, hexanal etc. These major components content was about 70~75% of the total flavor components. According to rise of deodorizing temperature, both ethane and aldehydes of 8 kinds content were in proportion to increase, but propane, pentane, hexane, octan, pentyl furan content were decreased by contraries, respectively. On the other hand, total flavor component content was appeared the lowest level at 245$^{\circ}C$ treating group, aldehydes content was in proportion to increase according to rise of deodorizing temperature. These phenomenons consider that the undesirable reactions such as partial auto-oxidation, degradation, polymerization and hydrolysis etc. by effecting factors of stripping steam and vacuum degree. Conclusively, deodorizing temperature under high temperature was undesirable for the minimization of off-flavor materials.

• Journal of Ginseng Research
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• v.18 no.1
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• pp.1-9
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• 1994

Sprague-Dawley rats were given freely with 15% ethanol (control) and 15% ethanol containing (1) 0.1% ginseng saponin, (2) 0.02% ginsenoside $Rb_1$, and (3) $Rg_1$ (tests) instead of water for 7 days and aldehyde dehydrogenase (ALDH) and monoamine oxidase (MAO) activity in different regions of brain were examined. In control group, total ALDH activity with indoleacetaldehyde and acetaldehyde as substrate in all different regions was lower than that of normal group except in the hippocampus. The inhibitory effect on the activity was prominent in the corpus striatum and was not in the hippocampus. However, low-$K_m$ ALDH activity in all different regions was much lower than that of normal group. A considerable decrease in mitochondria ALDH activity in cerebellum and striatum was also observed in control group. In test groups total, low-$K_m$, and mitochondria AkDH activities in all different regions were higher than those in control group. Although ALDH activity in the striatum of test group was higher than control group, it was relatively depressed as compared with normal. There was not found a remarkable difference in extent of stimulating effect on the AkDH activity according to the ginseng saponin components. When biogenic aldehydes were used as substrate, ALDH activity with 3,4-dihydroxy-phenylacetaldehyde (DOPAL) in all brain regions of control group was lower than that using 5-hydroxy-indoleacetaldehyde (HIAL) and 3,4-dihydroxyphenylglycolaldehyde (NORAL) as substrate. In control group, ALDH activity with biogenic aldehydes above mentioned was markedly inhibited in the striatum contrary to other regions. The higher ALDH activity with biogenic aldehydes in test group than in control was found in the striatum, cerebrum, and cerebellum. MAO activity in the cerebellum was inhibited in control group and slightly increased in test group. The results of present study suggest that the corpus striatum is significantly affected by ethanol exposure while the hippocampus is not and that ginseng saponin fraction and ginsenosid es might have a preventive effect against depression of brain ALDH activity by chronic administration of ethanol.

• Journal of the Korean Chemical Society
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• v.51 no.3
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• pp.232-239
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• 2007

The reaction of 1,1'-bis(dimethylsilyl)ferrocene with various aldehydes in the presence of a catalytic amount of Ni(PEt3)4 lead to the acyclic products by monohydrosilylation. The same reaction in the presence of a catalytic amount of (C2H4)Pt(PPh3)2 leads to the different cyclic six membered ring compound by double silylation. Platinum catalyzed double silylation of 4-cyanobenzaldehyde was generated 5,6-ferrocenylene-1,1,4,4,-tetramethyl-2-oxa-2- cyanophenyl-1,4-disylacyclehexane which was crystallized to have crystal structure.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• v.2 no.1
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• pp.49-56
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• 1998

This study identified the fumes produced from the cooking of the seasoned meats containing various condiments such as garlic, onion, pepper, soy sauce, and sesame oil. Concentrations, at the breathing zone of the cook, of volatile organic compounds (VOCs) and aldehydes included in the cooking fumes of seasoned meats were identified. Many chloro and fluoro-aliphatic hydrocarbons, aromatic hydrocarbons, ketones, and aldehydes, which could be carcinogen suspecting chemicals, were producing from the cooking fumes of the seasoned meats. This study also identified the ventilation efficiencies of the cooking fumes of the six exhaust ventilation systems, which were widely being used in the general apartments, houses, and small-food factories. For a comparison of the ventilation efficiencies of the systems, acetaldehyde was chosen as a marker pollutant and its concentrations at the breathing zone of the cook were identified. The laboratory fume hood showed the best ventilation efficiency of the six ventilation systems studied, and then the lateral hood ventilation and the down draft ventilation followed the laboratory fume hood. Finally, this study identified that both a wall factor nearby pollutant sources and a distance factor between the hood face and pollutant sources should be also considered for an effective local exhaust ventilation system design.

• Archives of Pharmacal Research
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• v.25 no.3
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• pp.258-269
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• 2002

2-Thiouracil-5-sulfonylchloride 1 reacted with a series of aromatic and heterocyclic amines to give 2a-j. The same compound 1 was reacted with a series of sulphonamides giving different sulphonamides of type 3a-e. On the other hand compound 1 was allowed to react with p-aminoacetophenone givining compound 4 which in turn was allowed to react with derivatives of alkyl thiosemicarbazides to give thiosemicarbazones of type 5a-e, also compound 4 was monobrominated to give compound 6 which in turn was reacted thiosemicarbazones of some aldehydes to give the corresponding thiazole derivatives 7a-f. In the same time compound 4 was reacted with a series of aromatic and heterocyclic aldehydes givining chalcones 8a-g (Claisen-Schemidt reaction). Also compound 4 was allowed to react with a series of aromatic and heterocyclic aldehydes, ethyl cyano acetate and/or malononitrile, and ammonium acetate giving pyridine derivatives 9a-d and 10a-e respectively. The biological effects of some of the new synthesized compounds was also investigated.

• The Korean Journal of Food And Nutrition
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• v.30 no.1
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• pp.120-128
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• 2017

This study aimed to provide volatile flavor compounds of three onion products through thermal process and alcohol fermentation, to meet the quality standard of onion products. The identified components of onion extracts (OE) included 49 (18 sulfur-containing compounds, 5 alcohols, 8 acids, 3 ketones, 4 esters, 4 aromatic compounds, 2 aldehydes, 1 pyrazines and 4 miscellaneous compounds), and 55 (17 sulfur-containing compounds, 15 alcohols, 5 acids, 11 ketones, 3 aromatic compounds, 2 aldehydes and 1 pyrazine) in autoclave-sterilized onion extracts (SOE); and 69 (10 sulfur-containing compounds, 27 alcohols, 11 acids, 11 ketones, 6 esters, 1 aromatic compound and 3 pyrazines) in onion wine (OW), respectively. Among the major flavor classes, sulfur-containing compounds (36.8%), acids (31.3%) and aldehydes (13.6%) in OE were changed to alcohols (46.5%) and ketones (27.3%) in SOE whereas, alcohols (56.3%) and acids (26.6%) in OW. Moreover, 1,3-butanediol, 2,3-butanediol, and 3-hydroxy-2-butanone were highly detected in SOE whereas, acetic acid, 3-methylbutanol, 2-phenylethanol and 1,2,3-propanetriol in OW.

• Food Science of Animal Resources
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• v.21 no.3
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• pp.256-264
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• 2001

Pyrolysis/GC-mass spectrometry(Hewlet-Packard 5890GC/mass selective detector, 5971 BMSD), interfaced to a CDS Pyroprobe 1500 was optimized for rapid analysis of flavour compounds in Cheddar cheese. Twenty flavour compounds, including aldehydes(4), ketones(4), fatty acids(10), alcohol(1), and hydrocarbon(1), were identified from Cheddar cheeses. In total, Twenty-three flavour compounds aldehydes(2), ketones(8), alcohols(3), fatty acids(7), lactone(1), benzene derivative(1) and amide(1) were identified from two samples of accelerated-ripened Cheddar cheese treated with the proteolytic enzymes of Lactobacillus casei LGY. In total, Twenty-one flavour compounds; aldehydes(2), ketones(5), alcohols(2), fatty acids(11), and lactone(1) were identified from enzyme-modified cheese(EMC) treated with the combination of the proteolytic enzymes of Lactobacillus casei LGY and commercial endopeptidase or lipase. However, All the flavour compounds identified by pyrolysis/GC/MS in samples of ARC and EMC were not determined whether they are recognized as typical Cheddar flavour or not. More studies were requested on the development of methods for a rapid and convienent analysis of dairy fermented products using pyrolysis/GC-mass spectrometry.

• Journal of Environmental Science International
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• v.2 no.1
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• pp.49-56
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• 1993

This study identified the fumes produced from the cooking of the seasoned meats containing various condiments such as garlic, onion, pepper, soy sauce, and sesame oil. Concentrations, at the breathing zone of the cook, of volatile organic compounds (VOCs) and aldehydes included in the cooking fumes of seasoned meats were identified. Many chloro- and fluoro-aliphatic hydrocarbons, aromatic hydrocarbons, ketones, and aldehydes, which could be carcinogen suspecting chemicals, were producing from the cooking fumes of the seasoned meats. This study also identified the ventilation efficiencies of the cooking fumes of the six exhaust ventilation systems, which were widely being used in the general apartments, houses, and small-food factories. For a comparison of the ventilation efficiencies of the systems, acetaldehyde was chosen as a marker pollutant and its concentrations at the breathing zone of the cook were identified. The laboratory fume hood showed the best ventilation efficiency of the six ventilation systems studied, and then the lateral hood ventilation and the down draft ventilation followed the laboratory fume hood. Finally, this study identified that both a wall factor nearby pollutant sources and a distance factor between the hood face and pollutant sources should be also considered for an effective local exhaust ventilation system design.