• Bulletin of the Korean Chemical Society
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• 제32권12호
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• pp.4411-4414
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• 2011

• 한국식품영양과학회지
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• 제30권4호
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• pp.726-731
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• 2001

밤 가공공장에서 폐기되고 있는 밤의 귀피를 항산화 기능성 자원으로 활용하고자 밤 귀치의 methanol 추출물 및 용매획분을 benzoic acid 수산화법으로 hydroxyl radical 소거능과 ferric thiocyanate법으로 과산화물생성 억제능을 시험하였다. 대부분의 획분에서 항산화성을 보였으며 특히 ethyl acetate 획분에서 BHA나 $\alpha$-tocopherol과 거의 유사한 rkdgkshydroxyl radical 소거능과 지질과산화물생성 억제능을 보였다. Ethyl acetate 획분으로부터 항산화성 물질을 분리하기 위하여 Sephadex LH-20 column chromatography 및 prep HPLC를 행하여 단일 물질로 정제하였다. 분리 정제된 물질을 $^{1}$H-NMR과 $^{13}$C-NMR로 구조 분석한 결과 gallic acid로 동정하였다. 페놀산을 GC로 분석한 결과 밤 귀피의 주요 페놀산으로 ellagic acid(172.22 mg%) 와 gallic acid(107.39 mg%)가 확인되었다.

• 한국식품위생안전성학회지
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• 제14권2호
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• pp.140-145
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• 1999

Analytical method for preservatives in food was developed using gas chromatography/mass spectrometry (GC/MS). Propionic acid, sorbic acid, benzoic acid, ethyl salicylate, ethyl p-hydroxy benzoate, iso-propyl p-hydroxy benzoate, n-propyl p-hydroxy benzoate, iso-butyl p-hydroxy benzoate, n-butyl p-hydroxy benzoate, p-hydroxy benzoic acid and dehydro acetic acid were extracted from cooling beverage with diethyl ether. The polar hydroxyl and carboxyl groups of food preservatives were derivatized with N-methyl-N-tert-butyldimethylisilyl-trifluoroscetamide (MTBSTFA) to form the corresponding tert-bytyldimethyl-silylated derivatives, and submitted to GC/MS analysis. The mass spectra of the derivatives were investigated for the selection of monitoring ions for multi-residue analysis of 11 preservatives by GC/MS. The macro program was also developed for the qualitative analysis of these preservatives in food.

• 한국지반환경공학회 논문집
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• 제13권10호
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• pp.69-76
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• 2012

본 연구에서는 전자빔공정(Electron beam process, E-beam)에서 생성되는 수산화라디칼의 생성특성을 조사하였고, 이 공정에 첨가제로 과산화수소와 $Fe^{3+}-EDTA$을 이용한 펜타클로로페놀(Pentachlorophenol, PCP)의 분해 특성을 조사하였다. 이를 위해 수산화라디칼의 측정은 벤조산(Benzoic Acid, BA)에 의한 hydroxylation으로 생성된 hydroxybenzoic acid(OHBA)의 농도를 정량화하여 수행하였다. 실험결과, 실제 측정된 수산화라디칼의 농도는 예측된 수산화라디칼에 비해 낮은 농도로 나타났으며, 이것은 아마도 E-beam 에너지의 조사와 동시에 형성되는 다양한 반응성 화학종이 수산화라디칼을 스케빈져(scavening)할 것으로 생각되었다. 특히, 1mM 이하의 과산화수소 주입은 PCP 분해를 촉진시킬 수 있으나 그 이상의 과산화수소의 주입은 오히려 PCP의 분해를 감소시키거나 PCP의 부산물인 염소이온과 Carbon yield(%)를 증가시키는 요인으로 작용하였다. 반면에, $20{\mu}M$의 $Fe^{3+}-EDTA$ 첨가는 효과적으로 PCP를 제거하였고, 이에 따른 G-value도 증가한 것으로 나타났다. OHBA의 형성과 PCP의 분해를 고려하여 보면, 결과적으로 E-beam공정에 가하는 $Fe^{3+}-EDTA$의 첨가는 상대적으로 낮은 세기에서도 효과적으로 PCP를 처리할 수 있을 것으로 생각된다.

• Bulletin of the Korean Chemical Society
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• 제12권4호
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• pp.438-440
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• 1991

Each aqueous solution (pH = 1) of acetic acid, acetamide, and acetonitrile produces carbon dioxide and hydrogen at 300 K when irradiated in the presence of semiconductors such as titanium dioxide, platinized titanium dioxide, etc. Similar results were obtained for each of benzoic acid, benzamide, and benzonitrile. Based on the relative amount of carbon dioxide, nitrile is believed to be transformed into carboxylic acid through the intermediacy of amide. A mechanism in which hydrogen atom and hydroxyl radical are involved is presented.

• Toxicological Research
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• 제26권4호
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• pp.321-327
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• 2010

The ability of 80% ethanol extracts from five medicinal plants, Aralia continentalis, Paeonia suffruticosa, Magnolia denudata, Anemarrhena asphodeloides, and Schizonepeta tenuifolia, to neutralize hydroxyl radical, peroxyl radical and peroxynitrite was examined using the total oxyradical scavenging capacity (TOSC) assay. Peroxyl radical was generated from thermal homolysis of 2,2'-azobis(2-methylpropionamidine) dihydrochloride (ABAP); hydroxyl radical by an iron-ascorbate Fenton reaction; peroxynitrite by spontaneous decomposition of 3-morpholinosydnonimine N-ethylcarbamide (SIN-1). The oxidants generated react with $\alpha$-keto-$\gamma$-methiolbutyric acid (KMBA) to yield ethylene, and the TOSC of the substances tested is quantified from their ability to inhibit ethylene formation. Extracts from P. suffruticosa, M. denudata, and S. tenuifolia were determined to be potent peroxyl radical scavenging agents with a specific TOSC (sTOSC) being at least six-fold greater than that of glutathione (GSH). These three plants also showed sTOSCs toward peroxynitrite markedly greater than sTOSC of GSH, however, only P. suffruticosa revealed a significant hydroxyl radical scavenging capacity. Seven major active constituents isolated from P. suffruticosa, quercetin, (+)-catechin, methyl gallate, gallic acid, benzoic acid, benzoyl paeoniflorin and paeoniflorin, were determined for their antioxidant potential toward peroxynitrite, peroxyl and hydroxyl radicals. Quercetin, (+)-catechin, methyl gallate, and gallic acid exhibited sTOSCs 40~85 times greater than sTOSC of GSH. These four components also showed a peroxynitrite scavenging capacity higher than at least 10-fold of GSH. For antioxidant activity against hydroxyl radical, methyl gallate was greatest followed by gallic acid and quercetin. Further studies need to be conducted to substantiate the significance of scavenging a specific oxidant in the prevention of cellular injury and disease states caused by the reactive free radical species.

• Food Science and Biotechnology
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• 제14권3호
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• pp.371-374
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• 2005

The compositions and antioxidant activities of tree and hydrolyzed phenolic acids, which are aglycones of esterified phenolic acids, in wild ginseng leaves were investigated. The contents of tree and hydrolyzed phenolic acids in the wild ginseng leaves were $422.4\;{\pm}\;3.5$ and $319.6\;{\pm}\;5.7\;mg/100\;g$, respectively, as gallic acid equivalents. Free phenolic acids were composed of 55.3% benzoic acid derivatives and 44.6% phenylpropanoids. The major constituents of free phenolic acids in the ginseng leaves were syringic (139.4 mg/l00 g) and sinapic (131.2 mg/100 g) acids. On the other hand, hydrolyzed phenolic acids in the ginseng leaves were mainly composed of caffeic (59.4 mg/100 g), ferulic (49.5 mg/100 g), and p-coumaric (33.8 mg/100g) acids. Phenylpropanoid content was higher (82.7%) than benzoic acid derivatives (17.3%). $IC_{50}$ values of DPPH radical scavenging activity were $10.2\;{\mu}g/mL$ for tree phenolic acids and 8.0 mg/mL for hydrolyzed phenolic acids, as gallic acid equivalents. Hydrolyzed phenolic acids also exhibited higher hydroxyl and superoxide radical scavenging activities than free phenolic acids did. These results indicated that the antioxidant activities of the wild ginseng leaves were correlated more closely with phenylpropanoid contents than with total amount of phenolics.

• Bulletin of the Korean Chemical Society
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• 제27권11호
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• pp.1785-1790
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• 2006

A novel kinetic method for determination of $HO_2{^{\cdot}}/O_2{^{{\cdot}-}}$ in ozone decomposition in water is described. In this study, potential interferences of $O_3$ and the hydroxyl radicals, $^{\cdot}OH_{(O3)}$, are suppressed by $HSO_3{^-}/SO_3{^{2-}}$. $HO_2{^{\cdot}}/O_2{^{{\cdot}-}}$ formed in ozone decomposition reduces $Fe^{3+}$-EDTA into $Fe^{2+}$-EDTA and subsequently the well-known Fenton-like (FL) reaction of $H_2O_2$ and $Fe^{2+}$-EDTA produces the hydroxyl radicals, $^{\cdot}OH_{(FL)}$. Benzoic acid (BA) scavenges $^{\cdot}OH_{(FL)}$ to produce OHBA, which are analyzed by fluorescence detection (${\lambda}_{ex}=320nm$ and ${\lambda}_{ex}=400nm$). The concentration of $HO_2{^{\cdot}}/O_2{^{{\cdot}-}}$ in ozone decomposition has been determined by the novel kinetic method using the experimentally determined half-life ($t_{1/2}$). The steady-state concentration of $HO_2{^{\cdot}}/O_2{^{{\cdot}-}}$ is proportional to the $O_3$ concentration at a given pH. However, the steady-state concentration of $HO_2{^{\cdot}}/O_2{^{{\cdot}-}}$ in ozone decomposition is inversely proportional to pH values. This pH dependence is due to significant loss of $O_2{^{{\cdot}-}}$ by $O_3$ at higher pH conditions. The steady-state concentrations of $HO_2{^{\cdot}}/O_2{^{{\cdot}-}}$ are in the range of $2.49({\pm}0.10){\times}10^{-9}M(pH=4.17){\sim}3.01({\pm}0.07){\times}10^{-10}M(pH=7.59)$ at $[O_3]_o=60{\mu}M$.

• 한국자원식물학회지
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• 제26권3호
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• pp.355-361
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• 2013

The present study attempts to evaluate antioxidant activities of extracts from Abeliophyllum distichum. Nakai flower. The samples were collected in Jangyyeon-myeon, Goesan-gun, Korea and extracted with either hot-water or ethyl acetate (EtOAC). In DPPH, hydroxyl radical scavenging activity and $Fe^{2+}$ chelating activity of EtOAC extracts were 93.41%, 98.43%, and 7.38%, while those of hot-water extracts were 86.93%, 41.33% and 47.68% at 200 ${\mu}g/ml$, respectively. In ${\varphi}X$-174 RF I plasmid DNA cleavage assay, the protective effects of EtOAC and hot-water extracts against oxidative DNA damage were 82% and 17% at 200 ${\mu}g/ml$, respectively. Both extracts showed the protective effect of DNA migration by oxidative stress in intracellular DNA migration assay. Both extracts had no cytotoxity in NIH3T3 cells. Several polyphenolic compounds were identified such as 2-methoxy-benzoic acid, vanillic acid, phytol and pulegone by GC/MS. These results indicated that extracts of Abeliophyllum distichum Nakai flower showed antioxidant activities and protective activities against oxidative DNA damage and showed the possibility to be used as an effective natural antioxidants.

• 대한본초학회지
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• 제25권4호
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• pp.55-59
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• 2010

본 연구에서는 연자육의 항산화 활성을 평가하기 위해 EtOAC 분획물과 열수 추출물을 이용하여 DPPH, Hydroxyl 라디칼 소거활성과 $Fe^{2+}$ 킬레이팅 활성을 측정하였다. 또한 산화적 DNA 손상억제 효과는 ${\phi}X$-174 RF I plasmid DNA cleavage assay를 통해 평가하였다. EtOAC 분획물은 $200{\mu}g/m{\ell}$에서 DPPH, Hydroxyl 라디칼 소거활성과 $Fe^{2+}$ 킬레이팅 활성이 각각 96.54%, 55.27%, 66.17%의 활성이 나타났으며, 열추 추출물에서는 각각 21.25%, 15.72%, 30.52%로 열수 추출물에 비해 EtOAC 분획물의 항산화 활성이 높은 것으로 나타났다. 또한 ${\phi}X$-174 RF I plasmid DNA cleavage assay에서 EtOAC 추출물은 $200{\mu}g/m{\ell}$에서 76%의 높은 억제 효과가 나타난 반면, 열수 추출물은 6%의 낮은 DNA 산화적 손상억제 효과를 나타내었다. 각 추출물의 총 페놀 함량을 조사한 결과 열수 추출물에 비해 EtOAC 분획물이 높은 것으로 나타났다. 항산화 활성과 DNA 산화적 손상억제 효과가 높은 EtOAC 분획물을 GC/MS에 의해 분석한 결과, Benzeneethanol, 3-methyl-Benzoic acid, 4-ethyl-Phenol, 2,4-bis(1,1-dimethylethyl)Phenol 등 페놀성 화합물이 다수 동정되었다. 본 연구결과에 의해 연자육은 항산화 및 암 예방적 소재로써의 새로운 기능성 식품소재로서 충분한 가능성이 있다고 판단된다.