• Title, Summary, Keyword: compounds

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Phenolic Compounds in Persimmon Fruits and Stabilization of Discoloring Compounds (감의 페놀성 화합물과 변색관련 물질의 안정화)

  • 박용곤;김홍만;강윤한
    • The Korean Journal of Food And Nutrition
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    • v.13 no.2
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    • pp.103-110
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    • 2000
  • This study was conducted to determine changes in phenolic compounds of astrigent persimmons before and after softening process and evaluate discoloring properties of major phenolic compounds. Phenolic compounds in soft persimmons were mainly composed of catechins and chlorogenic acid. Although contents of phenolic compounds were reduced during the softening process, little change in the ratio of catechins to total phenolic compounds was observed. Most of phenolic compounds in damaged astringents persimmons were existed in the high molecular weight fraction and more phenolic compounds were extracted at the temperature higher than room temperature. To evaluate discoloring abilities of phenolic compounds, phenolic compounds were dissolved separately into water or 80% methanol. With presence of various amounts of anti-discoloring agents such as vitamin C, citric acid, and L-cystein, (+)catechin was significantly reduced.

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Flavor and Taste-Active Compounds in Blue Mussel Hydrolysate Produced by Protease

  • Cha, Yong-Jun;Kim, Hun;Jang, Sung-Min
    • Preventive Nutrition and Food Science
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    • v.3 no.1
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    • pp.15-21
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    • 1998
  • Volatile flavor compounds in hydrolyzed blue mussel(HBM) produced by OptimaseTM APL-440, with untreated blue mussel(UBM) were compared. A total of 100 volatile compounds were detected in both HBM and YBM , consisting mainly of 25 aldehydes, 16 ketones, 17 alcohols, 8 nitrogen-containing compounds, 11 aromatic compounds, 8 terpenes, and 15 miscellaneous compounds. Levels of aromiatic compounds decreased after hydrolysis, whereas levels of 7 nitrogen-containing compounds increased. The compounds , 3-methylbutanal, (z)-4-heptenal, and (E,Z)-2-, 6-nonadienal , had the highest odor values in both samples. Total free amino acids in HBM were 21.89%(w/w) and increased by 3,4 times higher than UBM. glutamic acid and aspartic acid, having sour tastes, were the major taste-active compounds in HBM.

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Compilation of volatile flavor compounds in Cheonggukjang and Doenjang (청국장과 된장의 휘발성 향기성분 데이터베이스)

  • Baek, Hyung Hee
    • 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.

Analytical Methods for Phenolic Compounds in Water and Wastewaters(I) (Phenol류의 분석방법에 관한 연구(I))

  • 김낙주;신현진
    • Journal of Environmental Science International
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    • v.7 no.6
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    • pp.811-815
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    • 1998
  • Currently in Korea, standard operating procedure for the analyses of phenolic compounds in water is the spectrometric comparison of colors developed by 4-amino antipyrin with phenolic compounds. It is however that this method cannot identify individual compound and that some phenolic compounds do not react with 4-amino antipyrin. Spectrometric determinations of phenolic compounds were compared with chromatographic analyses of gas chromatography (GC) and high pressure liquid chromatography (HPLC) of various phenolic compounds. Individual phenolic compounds could be determined by both chromatographic methods but HPLC methods were more precise with lower detection levels in general.

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Volatile Compounds in Oyster Hydrolysate Produced by Commercial Protease

  • Cha, Yong-Jun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.24 no.3
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    • pp.420-426
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    • 1995
  • Volatile compounds in raw oyster and oyster hydrolysate produced with protease were compared by vacuum simultaneous steam distillation-solvent extraction/gas chromatography/mass spectrometry. Sixty-two volatile compounds were detected in both samples. Of these, 57 were positively identified, composed mainly of aldehydes(12), ketones(9), alcohols(14), nitrogen-containing compounds(9), acids(6), terpenes(4), and miscellneous compounds(8). Levels of acids decreased after hydrolysis, whereas several other compounds such as aldehydes, ketones, and nitrogen containing compounds increased. Pyrazines, found in high abundance, were only detected in oyster hydrolysate.

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Cure Characteristics of Carbon Block-Filled Rubber Compounds Composed of NR, SBR, and BR (NR, SBR, BR로 이루어진 고무배합물의 고무조성비에 따른 가황 특성)

  • Choi, Sung-Seen
    • Elastomers and Composites
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    • v.35 no.3
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    • pp.215-226
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    • 2000
  • Cure characteristics of carbon black-filled rubber compounds with different rubber composition were studied using a rheometer. The carbon black-filled rubber compounds with single, binary, and ternary rubber compositions of natural rubber (NR), styrene-butadiene rubber (SBR), and butadiene rubber (BR) were used. Delta-torques of the NR/BR- and SBR/BR-based compounds with a high BR content were higher than those of the single rubber-based compounds. For ternary rubber-based compounds, the delta-torques of the compounds were lower when the difference in the rubber content ratios was small than when it was big. Scorch and optimum cure times of the rubber compounds became shorter by increasing the content of NR in the compounds while those became longer by increasing the SBR content. Cure rates of the rubber compounds increased with a decrease of the SBR content in the rubber compounds. Reversion ratios decreased with an increase of the SBR content in the rubber compounds.

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Preparation of Alkyl and Aryl-thionocarbamate and their Anthelmintic action (Alkyl 급 Aryl thionocarbamate 류의 합성과 그 구충작용에 관한 연구)

  • 국채호
    • YAKHAK HOEJI
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    • v.7 no.2_3
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    • pp.58-66
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    • 1963
  • Alkyl-phenylthionocarbamates already have been investigated as anthelmintics. Especially ethyl-phenylthionocarbamate is noted for its anthelmintic action. Author studied methods for synthesizing Alkyl-phenylthionocarbamates, Alkyl-p-phenetyl thionocarbamates, Alkyl-cyclohexylthionocarbamates, 5 kinds for each. For alkyl radical $-CH_{3}$, $-C_{2}H_{5}$, -n-propyl, -isobuthyl, -n-buthyl, being chosen. Compounds VIII, X, XIII, XIV, and XV are new compounds. At the sametime author prepared 4 kinds of Arylthionocarbamates, among which XVII, and XIX being new compounds. (Table I) The anthelmintic action of these thionocarbamates has been examined through kymographic records indicating the action of neuromuscular preparation of Eisenia foetida Savigny in the various concentration fo above compounds: -Trendelenburg method. Santonine as the criterion of the estimation. (Table. II) 1. Compounds I-X could be prepared by method A or method B. method A in sealed tube brought on better yield and purity. 2. Compounds XI-XV couldn't be prepared by method A but by method B. 3. Arylthionocarbamates XVI, XVII, XVIII, and XIX couldn't be prepared by method A or method B but by method C. 4. Analyzed N. contained in all compounds. Analyzed C.H. and N. contained in unknown compounds, VIII, X, XIII, XIV, XV, XVII, and XIX. 5. Examination of anthelmintic action has been done under the advice of Prof. J.S.Oh medical college, Seoul Nat. University. 6. Compounds VI-X showed little action. 7. Compounds XVI-XIX showed almost no action. 8. Compounds XI-XV showed stronger action than compounds I-V, which was reported already as a usable anthelmintics. 9. Compounds XI, XII, XIII and XIV showed strongest actions, stronger than santonine as recorded on kymographion of the Trendelenburg method. Provided that, the toxity of these compounds found mild enough for human system, these compounds will serve as anthelmintics of greater powers than compounds I-V. 10. In Alkylthionocarbamates, R'NH-radical more influence on the anthelmintic action than ester radical(-OR).

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Comparison of chemical compounds of medicinal plant materials with compounds of domestic pharmacopoeias (식물 약재 구성성분과 국내 약전 성분과의 비교 연구)

  • Kim, Sang-Kyun;Lee, Seungho;Kim, Anna
    • The Korea Journal of Herbology
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    • v.31 no.5
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    • pp.55-62
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    • 2016
  • Objective : TM-MC was constructed to provide information on the chemical compounds of medicinal plant materials which were listed in Korean, Chinese, and Japanese pharmacopoeias. The aim of this study was to compare of the chemical compounds of TM-MC with those of domestic pharmacopoeias.Methods : First of all, TM-MC was updated on medicinal materials and chemical compounds which were extracted from articles up to the PubMed identifier of 26 millions. After searching for medicinal plant materials with information on their major compounds in Korean pharmacopoeias, we identified that the information on medicinal materials and chemical compounds were also existed in TM-MC. Then, we figured out how much the compounds have been studied by counting the number of articles for those compounds in TM-MC.Results : Information on 9 medicinal materials and about 1,700 compounds was newly added to TM-MC after manually curating 645 articles. Korean pharmacopoeias contained a total of 91compounds from 53 medicinal plant materials, while TM-MC provided information on the 89 compounds from the 53 medicinal materials in Korean pharmacopoeias. The compounds stated in Korean pharmacopoeias has been much studied by comparison with other compounds of each medicinal material in TM-MC.Conclusion : Most of chemical compounds stated in Korean pharmacopoeias were also listed in TM-MC, excluding two compounds. Thus, we concluded that information in TM-MC is mostly consistent with that of Korean pharmacopoeias. In the future, we will periodically update TM-MC with articles added to the MEDLINE.

The Stimultaneous Determination of Phenolic Compounds by GC and GC/MS

  • Kim, Jong-Bae;Park, Jyung-Rewng
    • Preventive Nutrition and Food Science
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    • v.3 no.2
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    • pp.111-118
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    • 1998
  • To develop a simple, rapid and simultaneous analytical method of phenolic compounds using gas chromatography (GC) and gas chromatography/mass spectrophometer (GC/Ms), this experiment was carried out to search the retention times of capillary columns and the characteristics of fragment ions in electron impact mass spectra. Most of trimethylsilyl derivatives and underivatized phenolic compounds were separated very well on three kinds of capillary columns(HP-1), Ultra-2 and HP-35). Quantitiative determination of phenolic compounds was achieved by internal standards (p-hydroxybenzoic acid iopropyl ester, p-hydroxybenzoic acid ethyl ester). Calibration plts were linear in the investigated range, and the limits of detection were about 5 ng at split mode method. When analyzed by three columns, theseparation times were fairly constant on two nonpolar columns, but a few compounds showed slightly different separation order by the itnermediate polar HP-35 column. The important characteristic patterns of TMS derivatives of phenolic compounds on the EI/MS spectrra appeared at the base peak of [M-15]+ ion and presented at high abundance in most TMS derivatives of phenoloc compounds. [M]+, [M-CH3-COO]+, [M-Si(CH3)4]+ and [M-Si(CH3)4 -CH3]+ also observed in mass spectra of these compounds . Although several compounds have the same retention times on GC column, it might be possible to identify these compounds by the different patternsof mass frgement ions. The TMS derivatives, thus , provide additional information for identification of phenolic compounds in biological systems.

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Analysis of Amadori Compounds in Tobacco Leaf by LC-MS/MS (LC-MS/MS를 이용한 담배 중 Amadori Compounds의 분석)

  • Min, Hye-Jeong;Kim, Young-Hoi;Lee, Jeong-Min;Jang, Gi-Chul
    • Journal of the Korean Society of Tobacco Science
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    • v.33 no.1
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    • pp.21-27
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    • 2011
  • Amadori compounds(1-deoxy-1-amino-2-ketoses) are important precursors of color, flavor and aroma produced in foods. Amadori compounds occur naturally in tobacco. The contribution of amadori compounds to smoke quality has been (of) interest because of their roles of the Maillard reaction in the leaf chemistry. The amounts of these compound in tobacco are affected by the processes of aging, drying and storage conditions. In this study, eight compounds were chemically synthesized because amadori compounds (have not been sold commercially these days.) were not available for obtaining commercially. The aim of this study was to develop the analytical method of amadori compounds in tobacco leaf by the liquid chromatography mass spectrometry using triple quadrupole analyzer(LC-MS/MS). This method was simple, rapid, selective and sensitive, and eight amadori compounds were simultaneously and quantitatively analyzed within 20 minutes. This method showed excellent accuracy and precision. Recovery rates of amadori compounds ranged from 86% to 102%, with relative standard deviation(RSD) ranged from 2.6% to 5.9%. This method was applied to analysis of amadori compounds contents of tobacco leaves in different varieties. Furthermore, it was expected that the method could be extended to the analysis of other amadori compounds.