• Title/Summary/Keyword: alcohol oxidation

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Chromophoric Structures of Alkali Lignin (알카리리그닌의 착색구조(着色構造)에 관(關)한 연구(硏究))

  • Yoon, Byung-Ho
    • Journal of the Korean Wood Science and Technology
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    • v.9 no.2
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    • pp.1-30
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    • 1981
  • To investigate the formation of the chromophoric structures taking place during the alkaline pulping vanillyl alcohol [${\alpha}-^{13}C$] guaiacylglycerol-${\beta}$-aryl ether [${\alpha}-^{13}C$ or ${\gamma}-^{13}C$] and phenylcoumarn [${\alpha}-^{13}C$] units as model lignins were treated with 1N sodium hydroxide at 165$^{\circ}C$ for 1.5-3 hours. From the chemical structures of the isolated products and $^{13}C$-NMR Spectra of the reaction mixtures, the main conclusion is as follows; 1) Condensation products of II-1-5 were identified from the reaction mixture of vanillyl alcohol treated with alkali and theses compounds afforded the quinonmethide structure(Fig. 3-7) by air oxidation. 2) Treatment of guaiacylglycerol-${\beta}$-aryl ether unit gave ${\varphi}$-aryl-${\beta}$-aroxy quinone structures (IV-15, IV-16), diguaiacyl-1, 4-penta-diene ${\beta}$, ${\beta}$'-diaroxyl distyrene methane unit, ${\beta}$-aroxy distyrene methane. These distyrene methanes of the compounds are transformed by air oxidation into the corresponding o-quinonemethide units (V-8, V-9). 3) On the treatment of phenylcoumaran, the stilbene derivative was formed in quantitative yield and dimerized(VI-11) in preference to oxidation to the corresponding extended quinone structures. The chromophoric structures taken place during the alkaline treatment of the model lignins are thought to be some important types in alkaline pulping on the basis of the reaction mechanism in this experiment.

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Effect of Anti-Microbial Materials on Storages of Ssamjang (항균물질 첨가에 의한 쌈장의 저장중 품질특성)

  • Kang, Bo-Ra;Im, Go-Eun;Kim, Dong-Han
    • Journal of Applied Biological Chemistry
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    • v.56 no.1
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    • pp.11-17
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    • 2013
  • The effect of additives on the quality of ssamjang was investigated during storage. The L-, a- and b-values of ssamjang decreased gradually during storage, and the total color difference (${\Delta}E$) increased in the control group. The gas production of ssamjang was reduced in K-sorbate, alcohol and mustard added groups. The number of yeast increased rapidly up to 6 weeks of storage, then decreased in the mustard, alcohol, and K-sorbate added groups. The oxidation-reduction potential and water activity decreased until 6 weeks and 12 weeks, respectively, and then increased gradually. Titratable acidity increased with concomitant decrease in pH, however, it increased slightly in the K-sorbate and ethanol added groups. Reducing sugar content increased until 9 weeks of storage, except the turmeric added group. Alcohol content increased until 15 weeks in the Japanese apricot juice, and turmeric added group. The sensory test result for the taste, flavor and overall acceptability showed that mustard added ssamjang was more acceptable than other groups.

A fundamental study on ozone oxidation of humic substances (휴믹물질의 오존산화에 관한 기초연구)

  • 김은호;김영웅;손희종;장성호
    • Journal of environmental and Sanitary engineering
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    • v.14 no.3
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    • pp.10-21
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    • 1999
  • The purpose of study were to research the characteristics of water variation adding humic acids to distilled water after ozonation. Upon investigating pH variation with contact time after providing distilled water+air, distilled water+ozone and distilled water-humic acid-air in reactor, it reduced after 60 minute in inletting air and in spite of short contact time did suddenly in inletting ozone. TOC and UV-254 continued to increase with contact time of ozone and humic acids. $NH^{4+}-N$ did slowly increase or decrease after constant contact time of ozone, because $NH^{4+}-N$ was converted into $No^3-N$ by ozone. T-N did suddenly increase after 90minute, but T-P did rarely fluctuate for total experiment. Total 30 species of organic matter were detected by GS/MSD, but 14 species did really tend to increase except for matter identified in distilled water and blank test. Humic acids generated $aliphatic{\cdot}aromatic$ hydrocarbon, alcohol and amine etc., and did various matters without inflow course of contaminants.

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Anti-obesity Effect of Black Vinegar Fermented with Herbal Extracts

  • Lee, Dongsub;Park, Sangwook
    • Biomedical Science Letters
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    • v.23 no.4
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    • pp.402-405
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    • 2017
  • Vinegar has been widely produced for a variety of industrial and domestic use as well as medicinal use. For sale of the commercial vinegar with herbal extracts, we produced an experimental black vinegar through sequential fermentation of alcohol, followed by acetic acid according to the manufacturer's procedure. To investigate the effect of anti-obesity of black vinegar on biochemical values, we evaluated enzyme activities via acetyl-CoA carboxylase (ACC), which plays a critical role in the lipid metabolism. We found that increased phosphorylated adenosine monophosphate (AMP) activated protein kinase (AMPK) and ACC in L6 mouse muscle cells treated with the manufactured vinegar. Based on the results, supplementation of experimental herbal black vinegar inactivates ACC, enhancing the phosphorylation of AMPK. Thus, the lipid oxidation and inhibitory effect of fatty acid synthesis by the black vinegar expects to facilitate the anti-obesity activity.

Explorative and Mechanistic Studies of the Photooxygenation of Sulfides

  • Albini, Angelo;Bonesi, Sergio M.
    • Journal of Photoscience
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    • v.10 no.1
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    • pp.1-7
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    • 2003
  • The results of recent work on the dye-sensitized photooxygenation of sulfides is discussed. In the case of dialkyl sulfides, the weakly bonded adduct initially formed with singlet oxygen (the persulfoxide) decays unproductively unless protonation by an acid (an alcohol or a carboxylic acid) facilitates its conversion to the sulfoxide. The effect is proportional to the strength of the acid (eg., less than 0.1 % chloroacetic acid in benzene is sufficient for maximal efficiency) and corresponds to general acid catalysis, suggesting that protonation of the persulfoxide occurs. On the other hand, with sulfides possessing an activated hydrogen in ${\alpha}$ position (eg., benzyl and allyl sulfides), hydrogen transfer becomes an efficient process in aprotic media and yields a S-hydroperoxysulfoniumm ylide, possibly arising from a conformation of the persulfoxide that is different from the one protonated in the presence of acids. Calculations on some substituted sulfides support this hypothesis. This process, which leads to C-S bond fragmentation with formation of an aldehyde, may be viewed as a general method for the preparation of aryl and heteroaryl aldehydes. In this effort, mechanistic studies offered new hints on the structure of the intermediate persulfoxide.

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Effects of Turmeric (Curcuma longa L.) on the Physicochemical Characteristics of Kochujang during Fermentation

  • Kim, Dong-Han
    • Journal of Applied Biological Chemistry
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    • v.56 no.2
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    • pp.101-107
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    • 2013
  • Physicochemical properties of kochujang prepared with different concentration of turmeric were compared. The number of yeast and bacteria in the kochujang were low in the group with more than 1% of turmeric while the amylase and protease activity increased in the group with less than 1% of turmeric. The L- and b-values increased as the concentration of turmeric increased, however a-value decreased. The titratable acidity was low in the high percentage of turmeric added group. Oxidation-reduction potential increased in the later stage of fermentation with decrease in Aw. Reducing sugar and alcohol were high in than higher turmeric added group. Amino- and ammonia-type nitrogen were the highest in the 0.5% turmeric added group. The overall acceptability of kochujang was significantly more favorable (p<0.05) in the 0.25% turmeric added group than over 1% turmeric added one.

An Approach to the Enantioselective Synthesis of the Crucial Intermediate of Conformationally Locked Nucleosides (형태학적으로 고정된 뉴클레오사이드 주요중간체의 Enantioselective 합성법 탐색)

  • Kim, Soon-Ai;Kim, Hak-Sung
    • YAKHAK HOEJI
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    • v.54 no.6
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    • pp.474-480
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    • 2010
  • Conformationally locked nucleosides are important in searching selective agonists and antagonists for P2Y receptors. There were two previous synthetic works of the crucial intermediate, cyclopentenyl alcohol (3), which had some inefficiency like using too strong dianionic base and synthesis of racemate. Here we describes a facile synthesis of the intermediate using Sharpless epoxidation and the opening of epoxide ring using zinc, followed by Grubb's metathesis as key steps. The intermediate was converted to the southern bicyclo[3.2.0]heptane for confirming its usefulness.

Species Difference in the Inhibition of Alcoholdehydrogenase by cArnitine and Acetylcarnitine

  • Cha, Youn-Soo
    • Preventive Nutrition and Food Science
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    • v.4 no.1
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    • pp.75-78
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    • 1999
  • Acetylcarnitine, a metabilite of carnitine, has been porven to be a potent inhibitor of ethanol oxidation in hepatocytes. It inhibits the activity of alcohol dehydrognase (ADH), but not the microsomal ethanol oxidizing system. which was significatly inhibited by acetylcarnitine at NAD ; acetylcarnitine $\leq$1. the main objectives of his study were to ascertain the interaction between acetylcarnitine and NAD on ADH activity and to elucidate whether different species have different effects. Tehpost-mocrosomal supernatant (PMS) was prepared from normal rat, guinea pig, mouse and broilers by differential centrifugation . Horse and yeast ADH were purchased from the Sigma Chemical Co. Prepared and purchased ADH are used for determination of ADH activity in the presence or absence of carnitine and acetylcar- nitine. Binding studies showed that acetylcarnitine did bind to ADH in a dose realted manner when low NAD ; acetylcar- nitine ratio was provided. It was found that the inhibitionof ADH activity occurred only when NAD concentration was less than the inhibitor concentration . Crystalline and crude ADH preparation from different vertebrate species wer inhibited by acetylcarnitine, whereas the yeast ADH was not affected by acetylcarnitine.

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The Study of Environment Change for Iron Antiquities after Excavation (고대 출토 철제 유물의 환경 변화에 따른 고찰)

  • Moon, Whan-Suk;Kim, Byoung-Gun;Wi, Koang-Chul;Hwang, Jin-ju
    • 보존과학연구
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    • s.14
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    • pp.35-44
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    • 1993
  • The way of prevention for the continuous corrosion progress in iron antiquities after excavation and conservation treatment have been studied. The corrosion occuring have been found the oxidation of ferrous ions in the presence of chloride. The consideration to control the activity of chloride is important of controling relative humidity for the stable environment of the storage. One of the method that keeps archeological iron antiquities recommend the storage of special vinyl film(poly-vinyl alcohol film) with silica gel to control the relative humidity. Although this method is not permanent, it's very well efficiency of economy and convenience at present.

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Antioxidant Activities of Agrimonia pilosa Ledeb: In Vitro Comparative Activities of Its Different Fractions

  • Chen, Lei;Kang, Young-Hwa
    • Korean Journal of Plant Resources
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    • v.27 no.6
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    • pp.642-649
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    • 2014
  • The antioxidant potentials of the methanol extract and its various fractions from Agrimonia pilosa Ledeb were measured as 1,1-diphenyl-2-picrylhydrazyl (DPPH), and 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging abilities as well as the reducing power decreasing NO in vitro. The methanol extract of Agrimonia pilosa Ledeb showed significantly strong scavenging effects on free radicals of DPPH, ABTS, and NO. Hexane fraction (HF), ethyl acetate fraction (EF) and n-butyl alcohol fraction (BF) were prepared by solvent fractionation. By comparison of polyphenol contents among BF and HF, EF with high polyphenol contents showed the highest DPPH, ABTS, and NO scavenging effects with the value of 50.2%, 80.4%, and 65.7%, respectively, at the highest tested dose. HPLC analysis revealed the presence of various phenolic compounds in EF of Agrimonia pilosa Ledeb. These results suggest that EF could be considered as natural antioxidant sources and dietary nutritional supplements to prevent oxidation-related diseases.