• Title/Summary/Keyword: 페놀

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Enzymatic Synthesis of Polyphenol Glycosides by Amylosucrase (재조합 아밀로수크라아제를 이용한 효율적인 폴리페놀 배당체의 합성)

  • Park, Hyun-Su;Choi, Kyoung-Hwa;Park, Young-Don;Park, Cheon-Seok;Cha, Jae-Ho
    • Journal of Life Science
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    • v.21 no.11
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    • pp.1631-1635
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    • 2011
  • The capability of synthesizing polyphenol glycosides was examined using recombinant amylosucrase from the hyperthermophilic bacterium Deinococcus geothermalis. Based on the action mode of amylosucrase, sucrose and twenty-one polyphenols were used as a donor and acceptors respectively. The transglycosylation reaction by amylosucrase produced one or two major polyphenol glycosides depending on the type of polyphenols used. The synthesized polyphenol glycosides were detected by thin-layer chromatography. The structures of the newly synthesized polyphenol glycosides were predicted based on the transglycosylation mechanism of the enzyme. According to the acceptability of the polyphenols, the structural characteristics of polyphenol as an efficient acceptor were evaluated. The results indicate that amylosucrase is an efficient catalyst for the enzymatic synthesis of polyphenol glycosides, which have high potentials in food, cosmetics, and pharmaceutical industries.

Adsorption Behavior of Monosubstituted-Halophenols by Amberlite XAD Resins (Amberlite XAD 수지에 대한 일치환 할로 페놀들의 흡착거동에 관한 연구)

  • Lee, Taek Hyeok;Lee, Dae Un
    • Journal of the Korean Chemical Society
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    • v.34 no.3
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    • pp.267-279
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    • 1990
  • The adsorption mechanisms of phenols on XAD-2 and XAD-7 resins were studied by using the distribution coefficient(log Kd) measured in the optimum adsorption conditions. It was observed that the Langmuir adsorption isotherm, indicating a molecular size-dependent adsorption, was appropriate for characterizing the adsorption behaviors of phenols on XAD-2 and XAD-7 resins. The adsorption energies of phenols on XAD resins were calculated by Lennard-Jones potential equation. In the calculation of the adsorption energy, the molecular radii and dipole moments of the resins and phenols were calculated by their van der Waals volumes and Debye equation, respectively. The stacking factor (F) were determined from the radio of the equilibrium distance to the stacking distance of molecules. In order to explain the adsorption energy calculated from the stacking factor it was compared with the adsorption enthalpy for each of phenols which was experimentally determined by batch adsorption shake method. It was observed that the adsorption enthalpy of phenolate ions on the XAD resins was likely to be more seriously affected by dispersion interaction than by a dipole or a charge interaction.

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Analytical Determination of Alkylphenols, Chlorophenols and Bisphenol A in Biota Samples using Gas Chromatography/Mass Spectrometry (기체 크로마토그래피/질량분석기를 이용한 생물시료 중 알킬 페놀류, 클로로페놀류 및 비스페놀 A의 분석법)

  • Hong, Jongki;Kim, Hyup;Baek, In-Girl;Kim, Do-Gyun;Seo, Jung-Joo;Seo, Jong-Bok;Chung, Bong-Chul;Pyo, Hee-Soo;Kim, Kyung-Rae;Kim, Yong-Hwa
    • Analytical Science and Technology
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    • v.13 no.4
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    • pp.484-493
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    • 2000
  • The simultaneous analysis of alkylphenols, chlorophenols and bisphenol A in biota samples was performed by gas chromatography-mass spectrometry-selected ion monitoring mode. The phenols were extracted from sample with organic solvent and Forisil and Silica columns for clean-up procedure were compared. Recovery studies were performed at 1-ppm level of phenols added to each biota sample. Their recoveries ranged between 83 and 116% with coefficient of variations of 2.4-11.9%. To improve the detection limits of phenols, trimethylsilyl (TMS) derivatization was applied. The gas chromatographic properties of free phenols and TMS derivatized phenols were also investigated.

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Thermo-rheological behaviors of Phenolic Resins Blended with Petroleum-based Pitches for High Temperature Carbon Composites (석유계 피치가 첨가된 고온 탄소복합재용 페놀수지의 열 유변학적 거동 연구)

  • Yang, Jae-Yeon;Kuk, Yun-Su;Seo, Min-Kang;Kim, Byoung-Suhk
    • Composites Research
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    • v.33 no.6
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    • pp.329-335
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    • 2020
  • In this study, the thermo-rheological behaivors of petroleum pitches with different softening points were studied, and a B-stage phenolic resins/petroleum pitches blends were prepared by adding petroleum pitches to the phenolic resins. As a result, the petroleum pitch with different softening points decreased the fluidity of the petroleum pitch as the Quinoline insoluble (QI) content increased and showed the viscous properties of the solid. In addition, the effect of adding petroleum pitches having different softening points on the thermo-rheological properties of phenolic resins was investigated. When petroleum pitch with a high softening point was added, the fluidity of the phenolic resin was reduced, and the hardening behavior was fast. It was possible to control the curing rate and curing behavior of the phenolic resin by adding petroleum pitches of different softening points. Among them, the phenolic resin mixture to which P-Pitch 2 was added has a higher fluidity than other blends under the same curing temperature condition.

Evaluation of Heat Resistance of Lyocell-based Carbon/Phenolic for Aerospace (항공우주용 리오셀계 탄소/페놀릭 복합재료의 내열 성능 평가)

  • Seo, Sang-Kyu;Kim, Yun-Chul;Bae, Ji-Yeul;Hahm, Hee-Chul;Hwang, Tae-Kyung
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.49 no.5
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    • pp.355-363
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    • 2021
  • Heat resistance performance evaluation and thermal analysis were performed to confirm the applicability of the lyocell-based carbon/phenolic composite material for heat-resistant parts for aerospace. Heat resistance performance evaluation of carbon/phenolic was conducted by Thermal Protection Evaluation Motor (TPEM). In this paper, boundary layer integration code considering the boundary layer analysis of combustion gas and MSC-Marc 2018 considering ablation and thermal pyrolysis were used for the thermal analysis. The ablation and thermal insulation performance were analyzed by the pressure curve of test motor and the cut carbon/phenolic specimens. The thermal response of the lyocell-based carbon/phenolic material was similar to that of the rayon-based carbon/phenolic material. Based on the results through the combustion test, the applicability of heat-resistant parts for aerospace to which domestic lyocell-based carbon fibers were applied was confirmed.

Separation of Phenol from Waste Water (모사폐수로부터 페놀의 분리)

  • 한성록;유홍진
    • Proceedings of the KAIS Fall Conference
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    • 2002.11a
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    • pp.283-286
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    • 2002
  • 막-용매 추출을 이용하여 모사폐수로부터 페놀을 분리하였으며, 이때 미세기공 비친수성 중공사형 모듈을 사용하였다. 전체적인 시스템은 향류, 및 병류로 운영되었으며, 유기오염물은 tube 안쪽으로, 용매는 shell쪽으로 흐르게 하였다. MIBK를 추출용매로 사용하였으며, 페놀의 분리효율은 향류 흐름이 병류흐름보다 더 우수함을 알 수 있었다.

Antioxidant and Antiviral Activities of Polyphenolics in Plum Wine (자두와인 내 폴리페놀 화합물의 항산화 및 항바이러스 활성)

  • Kang, Byung-Tae;Kwon, Dur-Han;Choi, Wha-Jung;Kim, Soon-Hee;Park, Dong-Cheol
    • Food Science and Preservation
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    • v.15 no.6
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    • pp.891-896
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    • 2008
  • Total phenolics and flavonoids, and the antioxidant capacity of plum cultivar wines (Prunus salicina L. cv. Soldam and P. salicina L. cv. Formosa) were determined using spectrophotometric methods. The total phenolic and flavanoid contents of Soldam wine were $478.4\;{\pm}\;5.6\;mg$ GAE and $202.4\;{\pm}\;7.5\;mg$ CE per L,respectively, and in Formosa wine were $200.6\;{\pm}\;7.5\;mg$ GAE and $64.4\;{\pm}\;6.8\;mg$ CE per L, respectively. Neutral and acidic phenolics in Soldam wine were extracted with ethyl acetate and 0.01 N HCl, respectively. In the 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging assay, neutral phenolics (64.5 EDA%) had $3{\sim}4$ times higher antioxidant activity than acidic phenolics (21.5 EDA%) and other related phenolic compounds such as chlorogenic acid (15.5 EDA%) and quercetin (24.6 EDA%) at a concentration of $100\;{\mu}g/mL$. The antiviral activities of neutral and acidic phenolics in Soldam wine were investigated in vitro using a virus-induced cytopathic effect (CPE) inhibition assay. Results showed that neutral and acidic phenolics at concentrations of $100\;{\mu}g/mL$ inhibited porcine epidemic diarrhea virus (PEDV) replication at rates of 78.12% and 58.37%, respectively. The inhibition rate of 10 g/mL neutral phenolics (69.42%) was higher than that of ribavirin as an antiviral reagent (57.86%). At concentrations of $100\;{\mu}g/mL$ or less, neutral and acidic phenolics of Soldam wine had no cytotoxic effect against vero cells.

A study on the oxidation characteristics of phenol on Pt anode (백금전극을 이용한 페놀의 산화특성에 관한 연구)

  • Kim, Hong-Soo;Nam, Jeong-Woo;Nam, Ki-Dae
    • Applied Chemistry for Engineering
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    • v.1 no.1
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    • pp.44-51
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    • 1990
  • The electrochemical oxidation behavior of phenol on platinum anode had been investigated by cyclic voltammetric method. The initial oxidation potential of phenol was dependent on the pH in acid solution. But in basic solution, it was held 033-0.40V(vs. S.C.E.). The peak current was proportional to the concentration of phenol and the optimum concentration was found to be about 0.1N. The oxidation reaction of phenol was found to be irreversible and controlled by diffusion.

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Properties and Thermal Characteristics of Phenol Foam for Heat Insulating Materials (단열재용 페놀폼의 물성과 열적특성)

  • Kim, Dong-Kwon;Lee, Soo-Bok
    • Applied Chemistry for Engineering
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    • v.17 no.4
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    • pp.357-360
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    • 2006
  • In this study, we studied the physical properties and application of PF foam as heat insulating materials. In the experimental results, the density of PF foam showed $0.030g/cm^3$ and the thermal conductivity showed $0.026kcal/m.h.^{\circ}C$. Also, thermal resistance of the prepared PF foam was volatilized about 71.7 wt% when the temperature was $500^{\circ}C$ (1 h). And the chemical structure of PF foam have a closed cell type in the important properties as heat insulating materials. Therefore, it was confirmed that the prepared PF foam had excellent performance as heat insulating materials.

Differences in Phenolic Compounds between Korean Ginseng and Mountain Ginseng (고려인삼과 장뇌삼의 페놀성 성분 비교 연구)

  • 유병삼;이호재;변상요
    • KSBB Journal
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    • v.15 no.2
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    • pp.120-124
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    • 2000
  • Differences in phenolic $\infty$mpounds were observed between cultured and mountain ginsengs. Cinnamic acid and p-hydroxy­b benzoic acid in Korean mountain ginseng and Chinese mountain ginseng were much higher than those in Korean ginseng. C Contents of the esculetin in Korean cultured ginseng and Korean mountain ginseng were higher than that in Chinese m mountain ginseng. The highest contents of esculetin in Korean mountain ginseng was$47.2\mu\textrm{g}/g$. Contents of the ferulic acid a and caffeic acid in red $\infty$lored Korean mountain ginseng were higher than any other ginseng.

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