• Title/Summary/Keyword: Carboxylic esters

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Evaluation of Volatile Compounds Isolated from Pork Loin (Longissimus dorsi) as Affected by Fiber Type of Solid-phase Microextraction (SPME), Preheating and Storage Time

  • Park, Sung-Yong;Yoon, Young-Mo;Schilling, M. Wes;Chin, Koo-Bok
    • Food Science of Animal Resources
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    • v.29 no.5
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    • pp.579-589
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    • 2009
  • This study was conducted to investigate the effects of heating, fiber type used in solid-phase microextraction (SPME, two phase vs three phase) and storage time on the volatile compounds of porcine M. longissimus dorsi (LD). Volatile compounds were measured using a gas chromatography and mass spectrometry (GC/MS) with a quadrupole mass analyzer. Among the volatile compounds identified, aldehydes (49.33%), alcohols (24.63%) and ketones (9.85%) were higher in pre-heated loins ($100^{\circ}C$/30 min), whereas, alcohols (34.33%), hydrocarbons (22.84%) and ketones (16.88%) were higher in non-heated loins. Heating of loins induced the formation of various volatile compounds such as aldehydes (hexanal) and alcohols. The total contents of hydrocarbons, alcohols, and carboxylic acids were higher in two phase fibers, whereas those of esters tended to be higher in three-phase fibers (p<0.05). Most volatile compounds increased (p<0.05) with increased storage time. Thus, the analysis of volatile compounds were affected by the fiber type, while heating and refrigerated storage of pork M. longissimus dorsi increased the volatile compounds derived from lipid oxidation and amino acid catabolism, respectively.

Continuous Surface Treatment and Dyeability of PTT Film via $UV/O_3$ Irradiation (UV/Ozone 조사에 의한 PTT 필름의 연속식 표면처리와 염색성)

  • Jang Jinho;Park Dae Sun
    • Textile Coloration and Finishing
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    • v.17 no.1
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    • pp.7-13
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    • 2005
  • Continuous and intense UV irradiation on PTT film using two types of UV bulbs at different irradiation power level was carried out to modify surface characteristics of the film including zeta potential, wettability, surface energy, and dyeability. ESCA analysis of the irradiated film showed higher O/C ratio than the untreated film indicating photooxidation of outer surface layer. ATR analysis showed that the ester bonds were broken and some new groups were produced such as carboxylic acid, phenolic hydroxy, and other esters, implying that ester bonds of PTT was responsible for the observed photooxidation effect. The surface of the treated PTT film became more hydrophilic and wettable to water, coupled with increased surface energy. Polar component of the surface energy increased and nonpolar component decreased with increasing irradiation energy. The treatment also decreased zeta potential of the modified surface and nanoscale roughness increased with increasing irradiation. The dyeability of the treated films to catonic dyes was significantly improved by electrostatic and polar interaction between dye molecules and the anionic film surface. The UV irradiation seems to be a viable polymer surface modification technology, which has advantages such as no vacuum requirement and continuous process unlike plasma treatment.

Synthesis of New Aromatic Ester Plasticizers and Their Endocrine Disrupting Screening (새로운 방향족 에스테르계 가소제 합성 및 내분비계 장애성 시험)

  • Yoo, Kyung-Ho;Ryu, Jae-Chun
    • Journal of the Korean Applied Science and Technology
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    • v.24 no.3
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    • pp.211-218
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    • 2007
  • Based on the Benzoflex (Vesicol Chemical Co.) as PVC plasticizer substituents for Di-n-octyl phthalate (DOP), a series of new aromatic carboxylic acid ester compounds were designed as plasticizers, synthesized, and screened for the endocrine disrupting activity. 2-Hydroxybenzoic acid (1) and 2-methoxybenzoic acid (2) as the commercially available starting materials were reacted with diethylene glycol (3) in the presence of p-toluenesulfonic acid using Dean-Stark column to give diethylene glycol di-(2-hydroxy)benzoate (4, KH01) and diethylene glycol di-(2-methoxy)benzoate (5, KH02), respectively. And diethylene glycol di-(3-pyridinyl) ester (7, KH03) and dipropylene glycol di-(3-pyridinyl) ester (9, KH04) were obtained in high yields by treatment of nicotinoyl chloride (6) with diethylene glycol (3) and dipropylene glycol (8) in the presence of triethylamine as a base. To determine the estrogenic disrupting effect of new synthetic phthalate analogues, E-screen assay method was used. Of these compounds, 4 (KH01) was found to be compound without endocrine disrupting effect.

Electromagnetic Interference Shielding Properties of CO2 Activated Carbon Black Filled Polymer Coating Materials

  • Hu, Quanli;Kim, Myung-Soo
    • Carbon letters
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    • v.9 no.4
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    • pp.298-302
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    • 2008
  • Carbon blacks could be used as the filler for the electromagnetic interference (EMI) shielding. The poly vinyl alcohol (PVA) and polyvinylidene fluoride (PVDF) were used as the matrix for the carbon black fillers. Porous carbon blacks were prepared by $CO_2$ activation. The activation was performed by treating the carbon blacks in $CO_2$ to different degrees of burnoff. During the activation, the enlargement of pore diameters, and development of microporous and mesoporous structures were introduced in the carbon blacks, resulting in an increase of extremely large specific surface areas. The porosity of carbon blacks was an increasing function of the degree of burn-off. The surface area increased from $80\;m^2/g$ to $1142\;m^2/g$ and the total pore volume increased from $0.14073\;cc{\cdot}g^{-1}$ to $0.9343\;cc{\cdot}g^{-1}$. Also, the C=O functional group characterized by aldehydes, ketones, carboxylic acids and esters was enhanced during the activation process. The EMI shielding effectiveness (SE) of raw N330 carbon blacks filled with PVA was about 1 dB and those of the activated carbon blacks increased to the values between 6 and 9 dB. The EMI SE of raw N330 carbon blacks filled with PVDF was about 7 dB and the EMI SE increased to the range from 11 to 15 dB by the activation.

Reduction of Representative Organic Functional Groups with Gallane-Trimethylamine

  • 최정훈;오영주;김민정;황북기;백대진
    • Bulletin of the Korean Chemical Society
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    • v.18 no.3
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    • pp.274-280
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    • 1997
  • The rates and stoichiometry of the reaction of gallane-trimethylamine with selected organic compounds containing representative functional groups were examined in tetrahydrofuran solution under standardized conditions (THF, 0 ℃). And its reducing characteristics were compared with those of aluminum hydride-triethylamine(AHTEA). The rate of hydrogen evolution from active hydrogen compounds varied considerably with the nature of the functional group and the structure of the hydrocarbon moiety. Alcohols, phenol, amines, thiols evolved hydrogen rapidly and quantitatively. Aldehydes and ketones were reduced moderately to the corresponding alcohols. Cinnamaldehyde was reduced to cinnamyl alcohol, which means that the conjugated double bond was not attacked by gallane-trimethylamine. Carboxylic acids, esters, and lactones were stable to the reagent under standard conditions. Acid chlorides also were rapidly reduced to the corresponding alcohols. Epoxides and halides were inert to the reagent. Caproamide and nitrile were stable to the reagent, whereas benzamide was rapidly reduced to benzylamine. Nitropropane, nitrobenzene and azoxybenzene were stable to the reagent, whereas azobenzene was reduced to 1,2-diphenylhydrazine. Oximes and pyridine N-oxide were reduced rapidly. Di-n-butyl disulfide and dimethyl sulfoxide were reduced only slowly, but diphenyl disulfide was reduced rapidly. Finally, sulfones and sulfonic acids were inert to the reagent under the reaction.

Flavor Components in the Bellflower Roots (Platycodon glaucum Nakai) (도라지 뿌리의 향기성분에 관하여)

  • Chung, Tae-Yung;Kim, Jeong-Lim;Hayase, Fumitaka;Kato, Hiromichi
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.16 no.2
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    • pp.136-146
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    • 1987
  • Flavor components were trapped by stimultaneous steam distillation-extraction method for investigating it in the bellflower roots and fractionated into four groups such as a neutral, a basic, a phenolic and an acidic fraction. An acidic fraction methylated with diazomethane solution and three others were analysed by GC and GC-MS equipping a fused silica capillary column, and S-containing compounds in these were detected with a flame photometric detector (FPD). The total of one hundred and three compounds from the bellflower roots were identified: they were 6 aliphatic hydrocarbons, 10 aromatic hydrocarbons, 2 terpene hydrocarbons, 12 alcohols, 8 terpene alcohols, 17 aldehydes, 3 terpene aldehydes, 5 ketones, 5 esters, 3 furans, 2 thiazoles, 2 lactones, 2 sulfides, 9 phenols, l2 carboxylic acids and 5 others. The greater part of the others except carboxylic acids were identified from a neutral fraction of which was assumed to be indispensable for the reproduction of bellflower root odor in a sensory evaluation. As a result of a sensory evaluation, 1-hexanal, trans-2-hexenal, 1-hexanol, cis-3-hexenol, trans-2-hexenol, 1-octen-3-ol and so forth identified in a neutral fraction were considered to be the key compounds of grass-like odor in the bellflower roots.

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Selective Reduction with Zinc Borohydride. Reaction of Zinc Borohydride with Selected Organic Compounds Containing Representative Functional Groups (수소화붕소아연에 의한 선택환원. 수소화붕소아연의 대표적 유기화합물과의 반응)

  • Yoon Nung Min;Ho Jun Lee;Hye Kyu Kim;Jahyo Kang
    • Journal of the Korean Chemical Society
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    • v.20 no.1
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    • pp.59-72
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    • 1976
  • The addition of one mole of zinc chloride to 2.33 moles of sodium borohydride in tetrahydrofuran at room temperature gave a clear chloride-free supernatant solution of zinc borohydride after stirring three days and standing at room temperature.The approximate rates and stoichiometry of the reaction of zinc borohydride with 54 selected organic compounds were determined in order to test the utility of the reagent as a selective reducing agent. Aldehydes and ketones were reduced rapidly, aromatic ketones being somewhat slowly, and the double bond of cinnamaldehyde was not attacked. Acyl halides were reduced rapidly within one hour, but acid anhydrides were reduced at a moderate rate. Carboxylic acids, both aliphatic and aromatic, were slowly reduced to alcoholic stage. Esters were inert to this reagent but a cyclic ester, γ-butyrolactone, was slowly attacked. Primary amides were reduced slowly with partial evolution of hydrogen, whereas tertiary amides underwent neither reduction nor hydrogen evolution. Epoxides and nitriles were all inert, as well as nitro, azo, and azoxy compounds. Cyclohexanone oxime and phenyl isocyanate were reduced slowly but pyridine was inert. Disulfide, sulfoxide, sulfone and sulfonic acids were stable to this reagent.

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Zinc supplementation of lactating dairy cows: effects on chemical-nutritional quality and volatile profile of Caciocavallo cheese

  • Ianni, Andrea;Martino, Camillo;Innosa, Denise;Bennato, Francesca;Grotta, Lisa;Martino, Giuseppe
    • Asian-Australasian Journal of Animal Sciences
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    • v.33 no.5
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    • pp.825-835
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    • 2020
  • Objective: The aim of the present study was to investigate the effect of dietary zinc supplementation of Friesian cows on chemical-nutritional and aromatic properties of Caciocavallo cheese after 7 days (C7) and 120 days (C120) of ripening. Methods: Twenty eight Friesian cows, balanced for parity, milk production and days in milk, were randomly assigned to 2 groups. The control group (CG) was fed with a conventional complete diet, while the experimental group (zinc group, ZG) received a daily zinc supplementation of 60 mg for kg of dry complete feed. During the experimental period, the milk yield was monitored and samples of milk and caciocavallo cheese were collected and analyzed for chemical-nutritional composition and aromatic profile. Results: The enrichment of dairy cows diet with zinc, did not influence milk yield and composition, however a marked reduction of somatic cell count was evidenced. Both in milk and cheese the ZG samples were characterized by a lower concentration of satured fatty acids and an increase in oleic, vaccenic and rumenic acids. The aromatic profile of dairy products was also positively affected by dietary zinc intake, with an increase in concentration of carboxylic acids, esters and lactones. Conclusion: The present results suggest a positive role of dietary zinc intake in improving the quality of bovine milk and related cheese, in particular for the increase in concentration of bioactive fatty acids such as rumenic acid. The changes evidenced in cheese through the analysis of the volatile profile, would be consistent with the development of interesting organoleptic properties, although further evaluations should be performed to confirm the consumer acceptability of these changes.

Designs and Syntheses of Oxathiin Carboxanilide Analogues and their Antiviral Activities

  • Hahn, Hoh-Gyu;Rhee, Hee-Kyung;Lee, Chong-Kyo;Whang, Kyu-Ja
    • Archives of Pharmacal Research
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    • v.23 no.4
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    • pp.315-323
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    • 2000
  • Syntheses of new analogues of oxathiin carboxanilide (UC84) and their antiviral activities were described. The heterocyclic carboxylic acids including oxathiins (4), thiazines (9) and dithiins (13) in which the methyl was replaced either by lipophilic trifluoromethyl- or bulky phenylgroup were synthesized starting from $\beta$-keto esters (5). Reaction of 4, 9 and 13 with thionyl chloride followed by treatment of the substituted aniline 22 gave the corresponding carboxanilides (24a~24f). The carboxanilides were subjected to Laweson's reagent the corresponding thiocarboxanilides (24g~24k). The antiviral activities of the synthesized compounds against human immunodeficiency virus type 1 (HIV-1), poliovirus type 1 (PV-1 ), coxsackie B virus type 3 (CoxB-3), vesicular stomatitis virus (VSV) and herpes simplex virus type 1 (HSV-1) were presented. The antiviral activity against HIV-1 of dithiin carboxanilide (24e) was similar with that of UC84 (24a). The corresponding thiocarboxanilides (24g~24k) showed higher inhibitory activity against HIV-1 than the carboxanilides (24a, 24b, 24d, 24e). The compounds in which ether the lipophilic trifluorormethyl substituents (24d, 24f, 24i ,24k) or bulky phenyl substituent is present in the heterocyclic compounds showed lower inhibitory activity than that of the methyl substituents is present in the compounds against the HIV-1. But the trifluoromethylated dithiin (24f) showed higher inhibitory activity against PV-1 and CoxB-3 virus than commercial antiviral agents, ribavirin (RV).

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Selective Reduction with Lithium Borohydride. Reaction of Lithium Borohydride with Selected Organic Compounds Containing Representative Functional Groups (수소화붕소리튬에 의한 선택환원. 수소화붕소리튬과 대표적 유기화합물과의 반응)

  • Nung Min Yoon;Jin Soon Cha
    • Journal of the Korean Chemical Society
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    • v.21 no.2
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    • pp.108-120
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    • 1977
  • The approximate rates and stoichiometries of the reaction of lithium borohydride, with fifty two selected organic compounds containing representative functional groups under the standard condition (tetrahydrofuran, $0^{\circ}$), were studied.Among the active hydrogen compounds,primary alcohols and compounds containing an acidic proton liberated hydrogen relatively fast, but secondary and tertiary alcohols very sluggishly. All the carbonyl compounds examined were reduced rapidly within one hour. Especially, among the ${\alpha}{\beta}$-unsaturated carbonyl compounds tested, the aldehydes consumed one hydride cleanly, however the cyclic ketones consumed more than one hydride even at $-20^{\circ}$. Carboxylic acids were reduced very slowly, showing about 60% reduction in 6 days at $25^{\circ}$, however acyl chlorides reduced immediately within 30 minutes. On the other hand, the reductions of cyclic anhydrides proceeded moderately to the hydroxy acid stage, however the further reductions were very slow. Aromatic and aliphatic esters, with exception of the relatively moderate reduction of acetate, were reduced very slowly, however lactones were reduced at a moderate rate. Epoxides reacted slowly, but amides and nitriles as well as the nitro compounds were all inert to this reagent. And cyclohexanone oxime and phenyl isocyanate were reduced very sluggishly. Last of all, all sulfur compounds studied were inert to this hydride.

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