• Journal of Korean society of Dental Hygiene
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• v.8 no.4
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• pp.11-18
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• 2008

The purposes of this study were to examine the effect of 35% Carbamide Peroxide(CP) bleaching agent on the changes in physical and chemical characteristics of tooth. The effect of bleaching agent on enamel was analyzed using Hardness test, SEM and EDS. The microhardness between bleached groups after bleaching showed statistically significant difference according to the paired t-test. The bleached enamel surface showed apparent morphological changes compared to the enamel, which was stored in distilled water only. The difference of the total mineral contents for the distilled water and Carbamide Peroxide did not show statistical significance. These results demonstrated that bleaching using 35% Carbamide Peroxide were adversely affects application time of experimental group and may the safety of using these agents for a short time in dentist-monitored bleaching.

• Journal of the Korean Society of Food Science and Nutrition
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• v.13 no.3
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• pp.326-333
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• 1984

The oxidation rate of krill lipids is very slow and no peroxides are accumulated even after long storage. By means of various chromatographic techniques and mass spectrophotometry, the primary antioxidant has been identified as ${\alpha}$-tocopherol. The phospholipid fractions did not show any antioxidative activity but peroxide-decomposing properties of total lipids depended upon the phospholipid contents. The peroxide-decomposing activities of phospholipids were due to the presence of polar materials generated during the storage. The most peroxide-decomposing fractions of oxidized krill lecithin by DEAE-cellulose column chromatography was low-molecule fraction (mean molecular weight: 182) and high-molecule fraction (mean molecular weight: 1942) was the next. The separation of peroxide-decomposing properties from low-molecule fraction was achieved by partitioning between chloroform and methanol/water. The methanol/water fraction showed strong peroxide-decomposing activities and main component of this fraction was assumed hydroxyamine compounds derived from choline.

• BMB Reports
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• v.28 no.6
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• pp.490-493
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• 1995

We investigated the effect of hydrogen peroxide-treated metallothionein on the hepatic xanthine oxidase activity in vitro. When the metallothionein was preincubated with 1 mM of hydrogen peroxide, the activity of xanthine oxidase and type conversion were elevated dose-dependently by the addition of metallothionein into the reaction mixture. While increasing the treatment of hydrogen peroxide to the $50{\mu}g$of metallothionein, the xanthine oxidase activity and type conversion ratio were remarkably elevated dose dependently compared to the control. When cadmium ion was added to the reaction mixture, the increasing pattern of the enzyme activity was similar to the effect of hydrogen peroxide-treated metallothionein. DTT or penicillamine restored the increasing activity and type conversion of xanthine oxidase by the cadmium ion to the control level.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.6
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• pp.1379-1384
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• 2009

The purpose of this study is to investigate the effect of water extract from Artemisiae Argi Folium Fermented with Lactobacillus pentosus (AFL) on hydrogen peroxide production within human hepatocyte HepG2 cells treated with gallic acid, EtOH, nicotine, acetaminophen, and acetaldehyde. AFL (0~400 ug/mL) was treated with gallic acid, EtOH, nicotine, acetaminophen, and acetaldehyde. And the intracellular productions of hydrogen peroxide were measured by dihydrorhodamine 123 (DHR) assay. AFL showed the restoration of the intracellular productions of hydrogen peroxide which were reduced by gallic acid, EtOH, nicotine, acetaminophen, and acetaldehyde in HepG2 Cells. AFL could be supposed to have the hepatoprotective effect related with hepatocytologic signaling activity against gallic acid, EtOH, nicotine, acetaminophen, and acetaldehyde.

• Journal of environmental and Sanitary engineering
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• v.21 no.4 s.62
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• pp.11-18
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• 2006

This study was carried out to investigate the distribution of Vibrio parahaemolyticus in the Incheon adjacent sea, and antimicrobial effect on growth of Vibrio parahaemolyticus in lactic acid and hydrogen peroxide and combination of lactic acid and hydrogen peroxide. The detected strains were compared geographical, months and sample types. The distribution of Vibrio parahaemolyticus was high at Ganghwa county with 66.1%(336 samples), on 7-9 months with 72.4%(386 samples) and from tireland with 75.0%(90 samples), respectively. The minimun inhibitory concentration (MIC) of lactic acid in Vibrio parahaemolyticus were 1250 ppm at pH 6.5 and 7.0, 625 ppm at pH 6.0. respectively. The minimun inhibitory concentration (MIC) of hydrogen peroxide in Vibrio parahaemolyticus were 25 ppm at pH 6.5 and 7.0, 12.5 ppm at pH 6.0, respectively. MICs of combined treatment of lactic acid and hydrogen peroxide in Vibrio parahaemolyticus were 625 ppm of lactic acid with 12.5 ppm of hydrogen peroxide. The correlations between MICs of lactic acid and hydrogen peroxide in Vibrio parahaemolyticus were obtained through the coefficient of determination($R^2$). $R^2$ value were 1.0000. The antimicrobial effect of lactic acid and hydrogen peroxide in Vibrio parahaemolyticus could be confirmed from the result of this experiment.

• Journal of Physiology & Pathology in Korean Medicine
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• v.25 no.1
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• pp.78-83
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• 2011

The purpose of this study is to investigate whether the intracellular hydrogen peroxide productions of mouse macrophage RAW 264.7 are modulated by Red Ginseng-Ejung-tang water extract (ER) and White Ginseng-Ejung-tang water extract (EG). Red Ginseng-Ejung-tang were composed of Red Ginseng, Atractylodes rhizome white, Zingiberis Rhizoma Siccus, and Glycyrrhizae Radix. White Ginseng-Ejung-tang were composed of White Ginseng, Atractylodes rhizome white, Zingiberis Rhizoma Siccus, and Glycyrrhizae Radix. The intracellular hydrogen peroxide productions were measured by dihydrorhodamine 123 assay with spectrofluorometer (excitation 485 nm; emission 535 nm). For 4, 20, 24, 44, 48, 68, and 72 h incubation, ER significantly increased hydrogen peroxide productions of RAW 264.7 at the concentration of 25, 50, 100, and $200{\mu}g/mL$ (P <0.05). EG for 4, 20, 24, 44, and 48 h incubation significantly increased hydrogen peroxide productions of RAW 264.7 at the concentration of 25, 50, 100, and $200{\mu}g/mL$ (P <0.05). For 68 and 72 h incubation, EG at the concentration of 50, 100, and $200{\mu}g/mL$ significantly increased hydrogen peroxide productions in RAW 264.7 (P <0.05). These results suggest that ER and EG have the immune-enhancing properties related with their increasing effects on the intracellular hydrogen peroxide production of macrophage.

• Journal of environmental and Sanitary engineering
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• v.19 no.4 s.54
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• pp.69-75
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• 2004

The inhibitory effect of the food processing agent on growth of Escherichia coli O157:H7, Salmonella Enteritidis, and Listeria monocytogenes was performed with hydrogen peroxide and lactic acid, and combination of hydrogen peroxide and lactic acid. The minimun inhibitory concentration (MIC) of hydrogen peroxide in E coli O157:H7 was 100 ppm at pH 5.0, 6.0, 6.5 and 7.0, while in Listeria monocytogenes 25 ppm at PH 5.5, 6.0 and 50 ppm at PH 6.5, 75ppm at pH 7.0. MIC of lactic acid in E coli O157:H7 was 2500 ppm at pH 5.0, 6.0, 6.5 and 7.0. MIC of lactic acid in S. Enteritidis was 1250 ppm at pH 5.0, 2500 ppm at pH 5.5, 6.0, 5.5 and 7.0, while in L monocytogenes 625 ppm at pH 5.5 and 125 ppm at pH 6.0, 6.5 and 7.0. MIC of combined hydrogen Peroxide and lactic acid in E. coli O157:H7, S. Enteritidis, and L. monocytogenes was 75 ppm of hydrogen peroxide with 2500 ppm of lactic acid at pH 6.5. The correlations between MICs of hydrogen peroxide and lactic acid in E. coli O157:H7, S. Enteritidis and L. monocytogene were obtained through the coefficient of $determination(R^2)$. $R^2$ value were 0.9994, 0.9935 and 0.9283, respectively. The inhibitory effect of hydrogen peroxide and lactic acid in E. coli O157:H7, S. Enteritidis and L. monocytogenes could be confirmed from the result of this experiment. Therefore, it was expected that the food process would increase or maintain by using lactic acid together with hydrogen peroxide.

• Journal of Aquaculture
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• v.21 no.3
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• pp.172-175
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• 2008

We evaluated storage stability of hydrogen peroxide, sodium hypochlorite, glutaraldehyde and didecyl dimethyl ammonium chloride (DDAC). Hydrogen peroxide and DDAC have been stabilized for 6-month storage at room temperature and $4^{\circ}C$ after opening. However sodium hypochlorite and glutaraldehyde were degraded to 15% and 39% for 6 month storage at $4^{\circ}C$ after opening, respectively. Therefore we have to take special attention wherever long term storing hydrogen peroxide and DDAC, also organic contents and pH in water should be considered for effective application in fish farms.

• Elastomers and Composites
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• v.48 no.1
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• pp.18-23
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• 2013

Nylon 12 elastomer was slightly crosslinked in molten state by the addition of small amount of dicumyl peroxide (DCP) as a crosslink agent and triallycyanuate (TAC) as a co-agent during melt compounding at $160^{\circ}C$ in an internal mixer. The effect of the peroxide crosslinking on mechanical, dynamic mechanical and rheological properties of the nylon 12 elastomer was investigated by means of tensile testing, dynamic mechanical analysis (DMA) and small amplitude oscillating rheometer, respectively. With modification, there is an improvement in tensile modulus and Young's modulus with decease in elongation at break. DMA results for peroxide modified nylon 12 elastomers demonstrated that the glass transiaiton temperature of PTMG segment shifted to higher temperature and the storage modulus remained constant above the melting temperature of nylon 12 segments. Melt rheological studies revealed that the peroxide modified nylon 12 elastomer exhibited a more solid like behavior and stronger shear thinning behavior compared to neat nylon 12 elastomer, which was more prominent at higher TAC content in the polymer matrix. The peroxide modified nylon 12 elastomer exhibited good elastic recoverability and improved mechanical properties without sacrificing melt processibilty, and especially the service temperature range increased as compared to neat nylon 12 elastomer.

• Research in Plant Disease
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• v.28 no.4
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• pp.204-208
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• 2022

Hydrogen peroxide is an eco-friendly oxidizing agent, which has exhibited a broad spectrum of antimicrobial activity without adverse environmental impact. This study was conducted to investigate the antifungal effect of hydrogen peroxide treatment against Cylindrocarpon destructans, and consequently to evaluate its control efficacy against root rot disease of 2-year-old ginseng plants. Hydrogen peroxide treatment strongly inhibited the viability of C. destructans conidia in vitro. The hydrogen peroxide at a concentration of 300 mg/l significantly reduced disease infection of the ginseng root when treated to spore suspension (10⁷ conidia/ml). Spraying with 300 mg/l of hydrogen peroxide reduced the root rot disease of the ginseng sprouts by 15% compared to the untreated control at 14 days after the inoculation. However, 300 mg/l of hydrogen peroxide delayed the emergence of ginseng plants during sprouting under aeroponic conditions. Further works need to be done to provide an acceptable control efficacy of hydrogen peroxide against the disease and its good safety to ginseng plants.