• Journal of Applied Biological Chemistry
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• v.55 no.3
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• pp.157-161
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• 2012

The aim of this research was to investigate the industrial application of Sedum sarmentosum. Antibacterial activities of the n-hexane, methylene chloride (MC), ethyl acetate, and n-butanol fractions of S. sarmentosum were tested against Escherichia coli, Staphylococcus aureus, and Helicobacter pylori. The MC fraction showed the strongest antibacterial activity against E. coli, with an inhibition zone greater than 13 mm in disc assays. At $100{\mu}g/mL$, all fractions scavenged more than 50% of 1,1-diphenyl-2-picrylhydrazyl (DPPH) and hydroxyl radicals (${\cdot}OH$). In particular, the MC fraction showed the strongest scavenging activity against DPPH and ${\cdot}OH$. In addition, we found that treatment with the MC fraction inhibited the growth of H. pylori and gastric adenocarcinoma cells. The present results suggest that the MC fraction of S. sarmentosum would play the promising protective role against pathogenic bacteria and free radicals.

• Toxicological Research
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• v.23 no.2
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• pp.143-150
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• 2007

Although animal and epidemiological studies have suggested oxidative stress as an etiological factor in pathogenesis including cancer, inflammation, sepsis, fibrosis, cardiovascularlneurodegenerative diseases and aging-related disorders, conflicting results have been obtained in clinical trial with antioxidants. The reason for this discrepancy remains unknown but may be due, in part, to the lack of a validated assay system for evaluating antioxidant capacity. The antioxidant activity of a series of sugar alcohols against peroxyl radicals, hydroxyl radicals and peroxynitrites was determined by the total oxy-radical scavenging capacity (TOSC) assay and cell-based assay using H4IIE cells. Specific TOSC values calculated from the slope of the linear regression for erythritol, xylitol, sorbitol or mannitol against peroxyl radicals was $2.1{\pm}0.2,\;3.7{\pm}0.3,\;9.1{\pm}0.3$ or $8.7{\pm}1.1$ TOSC/mM, respectively. Specific TOSC values for erythritol, xylitol, sorbitol or mannitol against peroxynitrite was $1.9{\pm}0.3,\;3.9{\pm}0.4,\;7.8{\pm}0.7$ or $7.7{\pm}0.5$ TOSC/mM, respectively. These results suggest that oxy-radical scavenging capacity is dependent on the number of aliphatic hydroxyl group in sugar alcohols of monosaccharide. Tert-butylhydroperoxide (t-BHP)-induced cell toxicity determined by MTT assay was marginally attenuated by 10 mM erythritol, but completely inhibited by 10 mM xylitol, 2 mM sorbitol or 0.75 mM maltitol, a disaccharide alcohol. Oxidative stress markers, such as glutathione (GSH) and malondial-dehyde (MDA) levels, were measured in t-BHP-treated cells using HPLC equipped with a fluorescence detector and a reverse phase column. Erythritol did not change the levels of GSH and MDA in H411E cells treated with t-BHP. The t-BHP-induced changes in cellular GSH and MDA levels were ameliorated by 10 mM xylitol and completely blocked by 10 mM sorbitol and maltitol. These results indicate that sugar alcohols protect cells against oxidative stress via scavenging oxy-radical and suggest that TOSC assay in conjunction with cell-based assay is a valid method for evaluating antioxidant capacity of natural and synthetic chemicals.

• The Korean Journal of Pharmacology
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• v.21 no.1
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• pp.34-48
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• 1985

In vitro effects of nitrofurantoin, an antimicrobial agent for acute and chronic urinary tract infection, on the lung microsomal lipid peroxidation and the generation of reactive oxygen radicals were investigated to elucidate the biochemical mechanisms of its in vivopulmonary toxicity. The interaction of nitrofurantoin with porcine lung microsome resulted in significant lipid peroxidation. In addition, nitrofurantoin stimulated the generation of reactive oxygen radicals, $O^{-}_{2}{\cdot},\;H_2O_2$ as well as a highly reactive secondary oxygen species, $OH{\cdot}$. The stimulation of lipid peroxidation was inhibited not only by superoxide dismutase and catalase, but also by hydroxyl radical scavengers, mannitol and thiourea. Neither singlet oxygen $({^1}O_{2})$ was detected during the incubation of microsome with nitrofurantoin, nor lipid peroxidation was inhibited by singlet oxygen scavengers. When incubated anaerobically under the nitrogen atmosphere, the ability of nitrofurantoin to stimulatle lipid peroxidation was abolished. It appears that NADPH-dependent metaboliam of nitrofurantoin in pulmonary microsome under aerobic condition is accompanied by the stimulation of lipid peroxidation through the mediation of reactive oxygen radicals, particularly hydroxyl radical. It is strongly suggested from these results that the stimulation of pulmonary microsomal lipid peroxidation by the reactive oxygen radical may be a in vivo mechanism of pulmonary toxicity caused by nitrofurantoin.

• Journal of Life Science
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• v.23 no.1
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• pp.31-37
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• 2013

The present study aimed to investigate effects of ethanol extracts from Hydropsyche kozhantschikovi on cell and DNA damage caused by oxidative stress. In a radical scavenging assay, compared with ascorbic acid used as a control, the level of DPPH (1,1-diphenyl-2-picrylhydrazyl) and that of hydroxyl radicals in H. kozhantschikovi extracts were 60.0% and 43.7%, respectively. The ferrous iron chelating level was 37.5% compared to the chelating value of EDTA (ethylenediaminetetraacetic acid) as a positive control at the same concentration. To verify inhibitory effects of oxidative cell damage induced by reactive oxygen species (ROS), the relative level of lipid peroxidation and the expression level of the p21 protein were compared in extracts-treated and untreated groups. Lipid peroxidation was completely inhibited in the extracts-treated group compared with the radical-only treated group. The level of p21 protein expression was restored to 92.2% of p21 protein expression in the control sample. In addition, DNA cleavage inhibition in the H. kozhantschikovi extracts was 74.1% compared with that of the control group, suggesting that H. kozhantschikovi extracts repress DNA cleavage induced by ROS. Moreover, the phosphorylation ratio of the H2AX protein was 16.7% in the radical-treated group, indicating that the ethanol extracts inhibited 83.3% of DNA damage. Our findings suggest that ethanol extracts from H. kozhantschikovi are effective not only in repressing the oxidation of free radicals and highly toxic hydroxyl radicals, but also in decreasing cell and DNA damage caused by oxidative stress.

• YAKHAK HOEJI
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• v.52 no.5
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• pp.355-360
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• 2008

In this study we investigated antioxidant activity of against several free radicals and skin whitening effect of 70% ethanol extract (leaf extracts and branch/stem mixed) of Lindera obtusiloba BL. Antioxidant activity was assessed by DPPH, superoxide radical and hydroxyl radical assays. The Lindera obtusiloba BL. extract had antioxidant activity dose dependently with an ${IC}_{50}$ value of 243.14 and 181.10 ${\mu}g$/ml for DPPH, 165.77 and >1500 ${\mu}g$/ml for non-enzymatic system of superoxide radical assay, 35.47 and >100 ${\mu}g$/ml for enzymatic system of superoxide radical assay, 1.21 mg/ml for hydroxyl radical assay. In addition we tested tyrosinase inhibition activity and melanin contents on B16 melanoma F10. B16 melanoma cell was treated by such sample as 1, 5, 10 and 50 ${\mu}g$/ml for 72 hr and tyrosinase inhibition was tested. Melanogenesis was inhibited to 22% at the dose of 50 ${\mu}g$/ml and tyrosinase was inhibited to 45.2% at the same dose. In conclusion Lindera obtusiloba BL had potent antioxidant activity and inhibitory activity of tyrosinase and melanin formation. It could be developed as the health functional food and functional cosmetic resources.

• Journal of the Korean Society of Tobacco Science
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• v.12 no.1
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• pp.19-27
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• 1990

To evaluate tobacco quality, several mathods including sensory test, or measurement of some toxic compounds such as tar, nicotine and carbon monoxide in cigarette smoke have been used. However, many detrimental effects of smoking on the physiological functions including respiratory system reported were turned out to be the action of reactive oxygen species. Therefore, the amounts of oxygen free radicals such as superoxide, hydroxyl radical, even hydrogen peroxide in the cigarette smoke are thought the very important factors. In the present study, we have determined the generation of superoxide and the content of hydrogen peroxide using superoxide dismutase and catalase in the gas and particulate phases obtained from cigarette smoke, respectively. In the aqueous extracts of total particulate materials, suproxide and hydrogen peroxide were detected, and there was an excellent correlation between oxygen tint of oxygen free radicals in cigarette smoke may be a useful index for evaluation of cigarette quality in the aspect of smoking and health.

• Journal of Life Science
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• v.9 no.4
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• pp.466-472
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• 1999

These studies were designed to investigate the effects of pine (Pinus densiflora Sieb et Zucc.) needle extract (PNE) on oxygen radicals and their scavenger enzymes in liver membranes of Sprague-Dawley (SD) rats as a study on investigation of anti-aging effect and determination of chemical structures of PNE through the animal experiments. Male SD rats were fed basic diets (control group) and experimental diets (0.5% and 1.0%-PNE group) for 6 weeks. There were no significant differences in hydroxyl radical (·OH) formations of liver mitochondria and microsomes in 0.5%-PNE group, while ·OH formations were significantly decreased (10% and 18%, respectively) in liver mitochondria and microsomes of 1.0%-PNE group compared with control group. Microsomal hydrogen peroxides and cytosolic superoxide radicals were remarkably decreased (20% and 20∼25%, respectively) in 0.5% and 1.0%-PNE groups compared with control group. Mn-SOD activities in mitochondria were significantly increased about 10% in 1.0%-PNE group, while Mn-SOD activities in mocrosomes were remarkably increased (16∼20%) in 0.5% and 1.0%-PNE groups compared with control group. There were no significant differences in Cu, Zn-SOD activities of liver cytosol in 0.5% and 1.0%-PNE groups, while glutathione peroxidase (GSHPx) and catalase (CAT) activities were significantly decreased (28∼30% and 15∼30%, respectively) in liver cytosols of 0.5% and 1.0%-PNE groups compared with control group. These results suggest that these PNE may play a effective role in a attenuating a oxygen radical formations and increasing a scavenger enzyme activities.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.5
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• pp.1349-1355
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• 2005

The steamed root of Rehmannia glutinosa has been used for treatment of inner ear diseases, such as tinnitus and hearing loss in traditional Oriental Medicine. In the present study, we investigated the effect of ethanol extract of steamed root R. glutinosa (SRG) on cisplatin cytotoxicity of HEI-OC1 auditory cells. In addition, to investigate the mechanism of SRG on cisplatin cytotoxicity, the effects of SRG on lipid peroxidation as well as scavenging activities against various free radicals were measured in cisplatin-treated cells. Treatment of SRG protected cells from cisplatin and reduced lipid peroxidation in a dose-dependent manner. Furthermore, SRG demonstrated significant scavenging activity against various free radicals, including superoxide radical, hydroxyl radical, hydrogen peroxide, and DPPH radical. These results indicate that SRG protects cisplatin-induced damages of HEI-OC1 cells through inhibition of lipid peroxidation and augmenting scavenging activities against free radials.

• Journal of Society of Preventive Korean Medicine
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• v.1 no.1
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• pp.48-54
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• 1997

Scutellariae radix, has been used as a natural drug for fever, inflammation, cataract, and liver disease in traditional medicine. This study was performed in order to investigate the antioxidative effects of Scutellariae radix aqua-acupuncture solution (SRAS) on lipid peroxidation by free radicals. Lipid peroxidation levels were determined by TBA method during the autoxidation of linoleic acid. In this linoleic acid autoxidation system, SRAS markedly exhibited antioxidant activity, which inhibited 89% of linoleic acid peroxidation. SRAS showed scavenging effects on ${\alpha},{\alpha}-diphenyl-{\beta}-picrylhydrazyl$(DPPH) radical, inhibited superoxide generation in xanthine-xathine oxidase system, and also inhibited lipid peroxidation of rat liver tissue by hydroxyl radical derived from $H_2O_2-FE^{+2}$ system. These effects were similar to those of $dl-{\alpha}-tocopherol$, BHA and BHT. In addition, SRAS protected the cell death induced by ter-butyl hydroperoxide (t-BHP) and significantly increased cell viability in the normal rat liver cell (Ac2F). On the basis of these results, it is suggested that SRAS might play a protective role in lipid peroxidation by free radicals.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.2
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• pp.462-467
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• 2007

The radix of Pueraria thunbergiana BENTHAM (Leguminosae) is traditionally prescribed to attenuate the clinical manifestations of inner ear dysfunction and various clinical situations including fever, gastrointestinal disorders, skin problems, migraine headaches, lowering cholesterol and treating chronic alcoholism in Oriental Medicine. In the present study, we examined the effect of ethanol extract of P. thunbergiana radix (EPR) on cisplatin-mediated HEI-OC1 auditory cell death. In addition, to investingate the protection mechanism of EPR on free radicals. Treatment of EPR protected cells from cisplatin and reduced lipid peroxidation in a dose-dependent manner. Furthermore, EPR demonstrated significant scavenging activity against various free radicals, including superoxide radical, hydroxyl radical, hydrogen peroxide, and DPPH radical. These results indicate that EPR protects cisplatin-induced damages of HEI-OC1 cells through inhibition of lipid peroxidation and augmenting scavenging activities against free radials.