• Toxicological Research
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• 제14권4호
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• pp.541-545
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• 1998

This experiment carried out to compare the protective effects of some antioxidants to hydroxyl radicals in embryonic mouse whole brain tissue culture. The ICR mouse whole brain (13 embryonic day) was cultured in hydroxyl radical system in which radicals were generated by 20 mU / ml glucose oxidase (GO). In this experiment, to make ferrous iron from ferric iron, iron as an accelerator, and ascorbic acid as a reductant were used. For comparison of the protective effects to hydroxyl radicals, antioxidants such as desferrioxamine (DFX), laccase. water or ethanol extracts from Rhus Vemiciflua Stokes (RVS), and $\alpha$-tocopherol were used, because they relate to metal ion. The results of this experiment showed that all antioxidants protected effectively the cytotoxicity from hydroxyl radicals in the brain cultures. More than 70% of cell viabilities among different antioxidants was at 1 mM DFX, 1.43 $\mu\textrm{m}$ laccase, 12.5 $\mu\textrm{m}$ water extract, 12.5 $\mu\textrm{m}$ ethanol extract and 50 $\mu\textrm{m}$ $\alpha$-tocopherol individually, compared with 20 mU/ml GO alone. In comparison to the antioxidative activities of antioxidants, laccase and extracts from RVS showed strong antioxidative effects even at low concentration.

• Asian Pacific Journal of Cancer Prevention
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• 제13권7호
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• pp.3065-3071
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• 2012

Aim: The present investigation was to evaluate the effects of essential oils of Wedelia chinensis (Osbeck) on free radicals and in vivo antioxidant properties. Methods: Essential oils were extracted using hydro-distillation and compound analysis was performed by GC-MS analysis. Screening for inhibitory activity was conducted by DPPH and OH-scavenging assays. In addition an in vivo study was carried out in cell line implanted cancer bearing mice with assessment of levels of catalase, superoxide dismutase, glutathione peroxidase, lipid peroxidation, nitric oxide and reduced glutathione. Finally, lungs were dissected out for histopathology study of metastasis. Results: GC-MS analysis revealed the presence of carvocrol and trans-caryophyllene as the major compounds with 96% comparison with the Wilily and NBS libraries. The essential oil exhibited significant inhibition in DPPH free radical formation. Whereas reducing power and hydroxyl radical scavenging activity are dose dependent. When compared with the standard, it was found that the essential oil has more or less equal activity in scavenging free radicals produced. In the animal studies, the level of antioxidant enzymes catalase, superoxide dismutase and glutathione peroxidase, as well as glutathione, were found to be increased in treated groups whereas lipid peroxidation and nitric oxide were reduced. Histopathology report also shows that the essential oil has a significant combating effect against cancer development. Conclusion: In all the in vitro assays, a significant correlation existed between the concentrations of the essential oil and percentage inhibition of free radicals. The in vivo studies also has shown a very good antioxidant property for the essential oil during cancer development. From, these results the essential oil can be recommended for treating disease related to free radicals and to prevent cancer development.

• 대한한의학회지
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• 제32권1호
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• pp.141-150
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• 2011

Objectives: The aim of this study was to elucidate the antioxidant effect of solvent fractions of Angelica gigas root. Methods: The ethanol extract of Angelica gigas root was suspended in water and then partitioned with dichloromethane (MC Fr.), ethyl acetate (EA Fr.) and butanol (BuOH Fr.), sequentially. The antioxidant activities of solvent fractions of Angelica gigas root were evaluated for radical scavenging activity against stable free radicals (2,2-diphenyl-1-picrylhydrazyl) DPPH, hydrogen peroxide and superoxide anion radicals. In addition the antioxidant activities of solvent fractions of Angelica gigas root against peroxyl radicals, hydroxyl radicals and peroxynitrites were determined by the total oxy-radical scavenging capacity (TOSC) assay. Results: Among the solvent fractions of MC Fr., EA Fr., and BuOH Fr., BuOH Fr. was found to have stronger antioxidant activity with $IC_{50}$ values of 59.72, 14.36, 30.96 and $44.75\;{\mu}g/m{\ell}$ on the DPPH radical, nitrite, superoxide anion and hydrogen peroxide, respectively, than BHA used as a positive control. Moreover, specific TOSC values(564.8, 276.4 and 405.5 TOSC/mM) of BuOH fr. against peroxyl radicals, hydroxyl radical and peroxynitrite were 4 times higher than GSH (136.5, 67.4 102.6 TOSC/mM) used as a positive control. Conclusions: These results suggest that the BuOH fr. of Angelica gigas root has a high antioxidant activity and can be useful to develop functional food against oxidative stress conditions.

• 대한한의학회지
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• 제30권5호
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• pp.146-156
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• 2009

Objectives: The objective of this study was to investigate the antioxidant effects of manufactured Wen-pi-tang-Hab-Wu-ling-san (WHW$^{(R)}$) in vitro. Methods: WHW$^{(R)}$ was prepared by the pilot manufacture of WHW water extract from a GMP system appointed company. Antioxidative activities were determined by in vitro tests as follows: the scavenging activities of oxygen free radicals including 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, superoxide anion, hydrogen peroxide and nitric oxide radicals, as well as ferrous ion chelating capacity and Trolox equivalent antioxidant capacity (TEAC). Results: WHW$^{(R)}$ significantly scavenged oxygen free radicals such as DPPH (IC$_{50}$=115.28 $\pm$ 0.25 $\mu$g/$m\ell$), superoxide anion (IC$_{50}$=8.56 $\pm$ 0.08 $\mu$g/$m\ell$), hydrogen peroxide (IC$_{50}$=240.36 $\pm$ 3.41 $\mu$g/$m\ell$) and nitric oxide (IC$_{50}$=162.28 $\pm$ 0.21 $\mu$g/$m\ell$) radicals. WHW$^{(R)}$ also showed ferrous ion chelating activity (IC$_{50}$=543.19 $\pm$ 4.85 $\mu$g/$m\ell$) and Trolox equivalent effects (IC$_{50}$=45.311 $\mu$g/$m\ell$) in TEAC and ORAC assay, respectively. Conclusion: This study demonstrates that WHW$^{(R)}$ has strong antioxidative properties through free radical scavenging activity. These data suggest that WHW$^{(R)}$ be used as an antioxidant agent.

• Natural Product Sciences
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• 제16권3호
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• pp.169-174
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• 2010

The seed of Phaseolus calcaratus Roxburgh (PHCR) is traditionally used for anti-pyretic and antiinflammatory effects. Although these effects are believed to be related to its antioxidant potential, little information is available for the mechanisms by which PHCR seed might scavenge free radicals or otherwise act as an antioxidant. In the present study, we purified some fractions from the ethanol extract of PHCR seed and evaluated each fraction's ability to scavenge free radicals generated by cell-free systems. We also identified active compound that is putatively responsible for free radical scavenging by analyzing NMR spectra. PHCR samples exhibited a concentration-dependent radical scavenging activity against hydroxyl radicals, superoxide anions, and DPPH radicals. Of the samples tested, a methanol-eluted sub-fraction from the PHCR extract, named $FF_4$, scavenged these radicals more effectively than the other fractions. We identified catechin-7-O-$\beta$-Dglucopyranoside as the active compound responsible for free radical scavenging potential of $FF_4$.

• 한국식품과학회지
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• 제34권2호
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• pp.170-173
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• 2002

본 연구는 ESR spectroscopy를 이용하여 free radical 농도를 측정함으로써 밀가루와 찹쌀가루의 방사선 조사여부를 일정기간 후에도 확인할 수 있는지를 알아보았다. 밀가루와 찹쌀가루를 0, 0.1, 0.5, 1 및 2 kGy로 Co-60 감마선을 조사한 후, 이를 시료로 Bruker-EPR spectroscopy를 이용하여 측정하였다. 실험결과 비조사시료와 조사시료 모두에서 밀가루는 $g_1=2.006{\pm}0.0001$, 찹쌀가루는 $g_1=2.006{\pm}0.0002$에서 신호를 나타내었으나, 조사시료의 경우 비조사시료와 비교하여 신호의 크기가 매우 커서 비조사시료와 쉽게 구별할 수 있었다. 적용선량의 범위에서 $(0.1{\sim}2\;kGy)$ 조사선량이 증가함에 따라 free radical 농도는 비례적으로 증가하였으며, 선량의 증가에 따른 free radical 농도의 증가를 나타낸 $R^2$ 값은 $0.9995{\sim}0.9998$의 높은 값을 나타내었다. 또한 이들 신호는 4주간의 저장기간 후에도 관찰할 수 있어 ESR spectroscopy를 이용한 밀가루와 찹쌀가루의 방사선 조사여부 판별은 4주간의 저장후에도 측정 가능한 방법임을 알 수 있었다.

• 대한화학회지
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• 제27권5호
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• pp.320-329
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• 1983

$\alpha$-아미노알킬라디칼들에 대한 안정화에너지를 검토하기 위하여 반경험적 분자궤도함수계산법인 MINDO/3-RHF 방법을 이용하여 고찰하고 비경험적 방법인 ab initio 및 실험적인 연구결과들과 비교하였다. 결과로써 라디칼들의 안정화에너지는 ab initio결과와 일치하게 나타났으며 실험결과와는 상반되게 나타났다. 그리고 라디칼들의 구조도 구조연구를 위해 더 적합하다고 알려진 ab initio 결과와 다르게 나타났다. 그러나 여러가지 증거에 의해 안정화에너지에 관한한 실험과 이론관의 상반된 결과를 일으키는 2가지 요인즉 (1) 실험결과 처리에서의 오차 (2)이온에서의 correlation을 고려하지 않았다는 점 가운데 후자가 더 크게 작용한다는 것을 알 수 있었으며 정성적으로 correlation을 고려했을 때는 실험과 일치하는 경향을 얻었다. 결국 correlation을 고려한 방법을 썼을 경우 실험과 일치하는 경향성을 보일 것으로 예측되었다.

• Environmental Engineering Research
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• 제10권3호
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• pp.138-143
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• 2005

Laboratory batch experiments were conducted to evaluate the Fenton degradation rates of phenanthrene. Fenton reactions for the degradation of phenanthrene were carried out with aqueous and slurry phase, to investigate the effects of sorption of phenanthrene onto solid phase. Various types of surfactants and electrolyte solutions were used to evaluate the effects on the phenanthrene degradation rates by Fenton's reaction. A maximum 90% removal of phenanthrene was achieved in aqueous phase with 0.9% of $H_2O_2$ and 300 mg/L of $Fe^{2+}$ at pH 3. In aqueous phase reaction, inhibitory effects of synthetic surfactants on the removal of phenanthrene were observed, implying that surfactant molecules acted as strong scavenger of hydroxyl radicals. However, use of $carboxymethyl-{\beta}-cyclodextrin$ (CMCD), natural surfactant, showed a slight enhancement in the degradation of phenanthrene. It was considered that reactive radicals formed at ternary complex were located in close proximity to phenanthrene partitioned into CMCD cavities. It was also show that Fenton degradation of phenanthrene were greatly enhanced by addition of NaCl, indicating that potent radical ion ($OCI^-$) played an important role in the phenanthrene degradation, although chloride ion might be acted as scavenger of radicals at low concentrations. Phenanthrene in slurry phase was resistant to Fenton degradation. It might be due to the fact that free radicals were mostly reacting with dissolved species rather than with sorbed phenanthrene. Even though synthetic surfactants were added to increase the phenanthrene concentration in dissolved phase, low degradation efficiency was obtained because of the scavenging of radicals by surfactants molecules. However, use of CMCD in slurry phase, showed a slight enhancement in the phenanthrene degradation. As an alternative, use of Fenton reaction with CMCD could be considered to increase the degradation rates of phenanthrene desorbed from solid phase.

• 한국환경과학회지
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• 제17권6호
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• pp.671-677
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• 2008

We studied to determine quantitatively the radical species generated from humic acid (HA) solutions by irradiation(>400 mn). The formation of radical species from HA solutions was investigated with ESR spectroscopy. We gave ESR spectrum with g-value 2.0048 and line width 0.559mT, coincided with those of the semiquinone radical. 0.1 mg/L HA solution generated the radicals of $1.2{\times}10^{-6}M$, increased with increasing HA concentration. Also, pH and ionic strength effect of the amount of the semiquinone radical generate from HA solution. In this study, we have found that the singlet oxygen affects the semiquinone radicals generation in HA solution.

• Preventive Nutrition and Food Science
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• 제22권3호
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• pp.223-230
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• 2017

The purposes of this study were to produce polysaccharides from red pepper stems using different extraction methods and evaluate their chemical composition, in vitro biological capacities, and rheological properties. Two polysaccharides were extracted from red pepper stems using an autoclave and alkali treatments, and the extracts were named PAU and PAL, respectively. The contents of total phenolics and flavonoids were significantly higher in PAU than those in PAL. PAU exhibited greater scavenging activities on 2,2-diphenyl-1-picrylhydrazyl radicals, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt radicals, superoxide radicals, and nitrite compared to PAL, suggesting that PAU served as better antioxidants. Similarly, in vitro inhibitory abilities against carbohydrate hydrolyzing enzymes of PAU were higher than those of PAL. Steady shear rheological analysis demonstrated that PAU showed higher psuedoplastic shear-thinning behavior compared to PAL. Based on the results from dynamic shear rheological properties, it was found that both samples had predominantly viscous behavior rather than elastic behavior.