• Preventive Nutrition and Food Science
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• v.4 no.2
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• pp.92-96
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• 1999

The effects of aqueous extracts from Korean commercial teas on excessive free radicals were examined utilizing spin trapping, 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical and lipid peroxidation. A potent scavenging effect of green tea and oriental senna tea was dound using sipin trapping. The most effective teasagainst the DPPH radical was green tea, followed inorder by pine leak tea, Chinese gutta percha tea and orietnal senna tea. Similar to the effects of DPPH radical , green tea, pine leaf tea, Chinese gutta percha tea and oriential senna tea had an inhibitory effect on lipid peroxidation. These findings predict that Korean tea is a promising material for scavenging free radicals, and for curing diseases related to free-radical reactions.

• The Korean Journal of Physiology and Pharmacology
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• v.2 no.5
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• pp.629-635
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• 1998

It has been suggested that oxygen free radicals are involved in the initiation process of acute pancreatitis, although its pathogenesis is not clear. This study evaluates the roles of oxygen radicals and the effects of small molecular antioxidants (rebamipide, N-acetyl-cysteine, allopurinol, ${\beta}-carotene)$ on the development of cerulein-induced acute pancreatitis. Acute edematous pancreatitis was induced by the intravenous infusion of cerulein at supramaximal dose of 10 ${\mu}g/kg/hour$ for 3.5 hours. The effects of antioxidants, rebamipide (100 mg/kg, i.p.), N-acetyl-cysteine (200 mg/kg, i.v.), allopurinol (20 mg/kg/hour), ${\beta}-carotene$ (50 mg/kg, i.p.), were examined. Cerulein administration resulted in a significant increase in serum amylase activity and pancreatic malondialdehyde (MDA), but not glutathione peroxidase (GSHpx). The glutathione (GSH) content in pancreatic tissue decreased dramatically. Pretreatment of N-acetyl-cysteine significantly decreased the cerulein-induced hyperamylasemia and maintained GSH content in pancreas, but MDA was slightly decreased. In addition, N-acetyl-cysteine ameliorated histological damage. Allopurinol and ${\beta}-carotene$ attenuated cerulein-induced hyperamylasemia, but histologically there was no difference from control. These results indicate that oxygen free radicals play an important role in the initiation of experimental acute pancreatitis. N-acetyl-cysteine is an effective antioxidant that ameliorates the cerulein-induced acute pancreatitis, and the possible therapeutic application of antioxidants against acute pancreatitis needs a further evaluation.

• Journal of Preventive Medicine and Public Health
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• v.23 no.4 s.32
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• pp.371-390
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• 1990

Production of free radicals of superoxide anion in tissues by cadmium, activities of superoxide dismutase and catalase to protect tissue damages caused by the free radicals and ATPase that plays an important role in energy metabolism at cellular level were investigated. Experiments in vivo were conducted with liver, kidney and testicle tissue homogenates of rats adding $0.05{\sim}0.50mM$ cadmium chloride, and in vivo experiments administering single dose of 5 mg of cadmium/kg of body weight in 0.1% cadmium chloride solution intraperitoneally 48 hours prior to evisceration. Production of superoxide radicals in liver and testicle increased with addition of cadmium in vitro, but not in kidney. In vivo experiments, however, superoxide radicals slightly increased in liver and kidney but not in testicle. Superoxide dismutase (Cu, Zn-SOD and Mn-SOD), catalase and ATPase (total, $Mg^{++}-\;&\;Na^+,\;K^+-$) activity decreased in the presence of cadimium in dose dependent manner. Reduction of these enzyme activities varied not only with dosage of cadmium but also with type of tissue and between in vitro and in vivo experiment.

• Herbal Formula Science
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• v.10 no.2
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• pp.243-249
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• 2002

This study was performed to investigate the effects of fermented extract of Pinus densiflora (FPD) on oxygen radicals and $H_2O_2$-induced damage. The results are as follows: 1. The 1.1-diphenyl-2-picrylhydrazyl (DPPH) free radicals were considerably reduced by FPD and $IC_{50}$ value was showed the concentration of 20 ㎍／㎖. 2. The cytotoxicity did not observe by FPD treatment in A548 cells. 3. The $H_2O_2$-induced cell damage was recovered by FPD pretreatment in A549 cells. These results suggest that FPD, as a natural antioxidant, has scavenging effect of free radicals and protection effect from $H_2O_2$-induced cytotoxicity.

• Journal of Acupuncture Research
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• v.15 no.2
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• pp.135-145
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• 1998

Bupleury radix has been used for the treatment of fever, liver disease, inflammation in traditional medicine. The present study was carried out to evaluate the antioxidant effects of Bupleury radix aqua-acupuncture solution (BRAS) in vitro. Oxygen derived free radicals produced in the course of normal aerobic life, such as superoxide anion radical($O_2^-$ ), hydroxyl radicaI( OH), hydrogen peroxide($H_2O_2$) and singlet oxygen($^1O_2$) can attack polyunsaturated fatty acid in cell membranes, enzymes, other cell compounds, and give rise to lipid peroxidation, DNA damage, lipofuscin accumulation, structure alteration of cell membrane and cell death. In this study, antioxidant effects of BRAS on lipid peroxidation were determined according to the method of TBA. BRAS inhibited markedly peroxidation of linoleic acid during the autoxidation, and also inhibited lipid peroxidation induced by hydroxyl radical derived from $H_2O_2-Fe^{2+}$ in rat liver homogenate. And BRAS showed 30% scavenging effect on DPPH radical, also exhibited a 30% inhibitory effect on superoxide generation from xanthine-xanthine oxidase system. In addition, BRAS protected the cell death induced by tert-butyl hydroperoxide(t-BHP) and significantly increased cell viability in the normal rat liver cell(Ac2F).

• Journal of Radiation Industry
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• v.9 no.2
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• pp.57-62
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• 2015

In this study, we fabricated effect of storage conditions on graft of polypropylene (PP) non-woven fabric induced by electron beam. The electron beam irradiations on PP non-woven fabric were carried out over a range of irradiation doses from 25 to 100 kGy to make free radicals on fabric surface. The radical measurement was established by electron spin resonance (ESR) for confirming the changes of the alkyl radical and peroxy radical according to effect of storage time, storage temperature and atmosphere. It was observed that the free radicals were increased with irradiation dose and decreased with storage time due to the continuous oxidation. However, the radical extinction was significantly delayed due to reduced mobility of radicals at extremely low temperature. The degree of graft based on the analysis of ESR was investigated. The conditions of graft reaction were set at a temperature: $60^{\circ}C$, reaction time: 6 hours and styrene monomer concentration: 20 wt%.

• Preventive Nutrition and Food Science
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• v.12 no.3
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• pp.177-180
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• 2007

Tocotrienols (T3) are minor plant constituents found abundantly in rice bran, which provide a significant source of vitamin E in animal feeds. T3 was reported to have an intrinsic hypocholesterolemic effect by inhibiting HMG-Co A reductase. It has similar antioxidative properties as tocopherols in food and biological system due to their similar chemical structures. However, the antioxidant activity and mechanism of T3 to scavenge free radicals and to inhibit the peroxidation of linoleic acid are less understood. The purpose of this study was to investigate the scavenging effect of T3 on free radicals and its inhibition of peroxide formation. Free radical scavenging activity was monitored by the DPPH (1,1-diphenyl-2-picrylhydrazyl) method whereas inhibition of linoleic acid peroxidation was evaluated using the thiocyanate method. Thiobarbituric acid (TBA) test was used to determine malonaldehyde formation from linoleic acid peroxidation. Free radical scavenging activity increased with increasing concentration levels of T3. T3 exhibited 38.2, 78.6, 92.7 and 96.2% radical scavenging activity at concentrations of 2, 8, 32 and 128 ppm, respectively. At 128 ppm, it was highly effective in inhibiting linoleic acid peroxidation. The activity of T3 evaluated by the thiocyanate method showed low absorbance values indicating a high level of antioxidant activity. All treatments showed similar trends in antioxidant activity when evaluated by both the thiocyanate method and TBA test.

• Toxicological Research
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• v.11 no.1
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• pp.57-62
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• 1995

To investigate the ultrastructural changes of kidney and clarify to a cause of its changes in lead intoxicated rats, the 0.5% lead acetate administed orally to the rats and those were sacrifled at 2 day, 1, 2, 4, 6 and 8 week after the treatment of lead acetate. Each extirpated kidney was histopathologically examined under the electron microscopy and histochemical examination was also carried out. Concomitantly, the activity of free radical metabolizing enzyme was determined. The blood levels of lead concentration showed a gradual increase from the first group reaching the plateau at the one or two week group with the slightly decreasing value throughout the whole course of the experiment. And the urinary ALA concentration showed a gradual increase from the first group to the 8 week group. In the kidney tissue of rat sacrified at 6 week, the proximal tubular cells showed dilatation of endoplasmic reticulum, mitochondrial swelling, increased numbers of secondary lysosomes and myelin figure-like residual bodies on electron microscope and oxygen free radicals are identified by histochemistry on light microscope whereas there were no differences in the activity of catalase and glutathione peroxidase between the lead acetate treated group and control group. But the activity of xanthine oxidase was more increased in lead acetate treated rats than control group. Furthermore, the superoxide dismutase activity was significantly increased in the experimental group than the control group. In conclusion, it is assumed the kidney damage in lead intoxicated rat may be induced by free radicals.

• Advances in Traditional Medicine
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• v.8 no.3
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• pp.260-265
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• 2008

Annona reticulata belonging to the family Annonaceae is traditionally used as anthelmintic and it is reported to have anticancer activity. Free radicals are known to be involved in various types of diseases like cancer, diabetes, neurological disorders etc. The present study was aimed to evaluate free radical scavenging property of methanol extract of the leaves of Annona reticulata in some in vitro models e.g. DPPH, nitric oxide, superoxide and lipid peroxide radical model. The extract showed good dose-dependent free radical scavenging property in all the models. $IC_{50}$ values were found to be 3.22, 170.01, 25.12 and $140.12\;{\mu}g/ml$ respectively in DPPH, nitric oxide, superoxide and lipid peroxidation inhibition assays. Reductive ability of the extract was also tested based on potassium ferricyanide reduction where dose dependant reducing capability was observed. Measurement of total phenolic compounds by Folin-Ciocalteu's phenol reagent indicated that 1mg of the extract contained $146.20\;{\mu}g$ equivalent of pyrocatechol. The findings ascertain promising free radical scavenging property of the extract and the antioxidant property of the extract may be due to the high content of phenolic compounds.

• Korean Journal of Pharmacognosy
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• v.34 no.4 s.135
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• pp.324-326
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• 2003

The methanol (MeOH) extract and ist fractions of Taraxacum mongolicum (Compositae) were examined for their scavenging effects on 1,1-diphenyl-2- phenylhydrazyl (DPPH) and superoxide radicals, and hepatoprotective effects on tacrine-induced cytotoxicity in human hepatoma cell line, Hep G2 cells. Both methylene chloride $(CH_2Cl_2)$ and butanol (n-BuOH) soluble fractions of the MeOH extract showed the free radicals scavenging and hepatoprotective effects. From these results, it is suggested that hepatoprotective effect of these fractions partly relies on their free radical scavenging activity.