• Journal of Environmental Science International
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• v.13 no.6
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• pp.551-560
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• 2004

The feasibility and efficiency of the hydrogen peroxide produced by an electrolysis cell reactor was investigated, From regulating voltages for the given reaction time, the concentration of the hydrogen peroxide was gradually increased with increasing voltages. Optimal voltage range was found to be 10～15 V. The concentration of hydrogen peroxide was much higher with oxygen gas than without oxygen gas in the cathodic chamber. But there was a little difference in the generating rate of hydrogen peroxide regardless of the presence of nitrogen gas. Under given conditions, the maximum value of ICE(Instantaneous Current Efficiency) was about 38%, and then current density was 74 $mA/\textrm{cm}^2.$ The specific energy consumption was $0.694[kWh/kg-H_2O_2].$ Since Esp (Specific Energy Consumption)was very little value, It did not demand high energy in this system. Using the hydrogen peroxide gained in the experiment, Fenton's reaction was conducted and the removal of nitrobenzene, 3-chlorophenol and dye wastewater was studied. This results were very similar to the Fenton's reaction by using commercial hydrogen peroxide.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.264-264
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• 2017

Legumes are good sources of various nutrients. Among legumes, soybean and its flour are accessible foods to consumers. However, in case of soybean flour, there is a disadvantage of easily going rancid. Thus, this study aimed to investigate how the quality of soybean flour changes during storage according to the packaging materials and storage temperatures. The raw and roasted soybean flours were packed in two types of packaging, polyethylene (PE) and polypropylene (PP) film bags respectively, and stored at three different storage temperatures (4, 20, and $45^{\circ}C$) for 1 year. The acid value, conjugated diene value, peroxide value, p-anisidine value, thiobarbituric acid (TBA) value, lipoxygenase activity, and fatty acid content of raw and roasted soybean flours were measured at the point of starting storing, and after 1, 2, 4, 8, and 12 weeks of storage. The acid value of soybean flour was increased for 4 weeks and thereafter significantly decreased (p < 0.0001). The conjugated diene value was significantly increased after 4 weeks storage at $45^{\circ}C$ with PE and PP film bags (p < 0.0001). The peroxide value had no changes during 4 weeks storage at $45^{\circ}C$ with PE and PP film bags, and then those was dramatically increased after 8 weeks (p < 0.0001). The p-anisidine values in all of storage conditions were decreased after 4 weeks. Lipoxygenase activity was decreased at 12 weeks storage at $20^{\circ}C$ and $45^{\circ}C$ with PP film bags. Acid value had positive correlations with p-anisidine value (r = 0.30 and p < 0.0001) and lipoxygenase activity (r = 0.36 and p < 0.0001), and had negative correlations with conjugated diene value (r = -0.45 and p < 0.0001) and peroxide value (r = -0.25 and p < 0.001). Conjugated diene value had a high positive correlation with peroxide value (r = 0.76 and p < 0.0001), but that had a negative correlation with lipoxygenase activity (r = -0.51 and p < 0.0001). Peroxide value had negative correlations with p-anisidine value (r = -0.20 and p < 0.01) and TBA value (r = -0.15 and p < 0.05). The degree of reduction in fatty acid content of raw soybean flour was higher than the roasted soybean flour during the storage. Total fatty acid content had positive correlations with acid value (r = 0.45 and p < 0.0001) and p-anisidine value (r = 0.58 and p < 0.0001), but had a weak negative correlation with conjugated diene value (r = -0.19 and p < 0.01). This study showed how the rancidity of the raw and roasted soybean flours progressed during storage. Thus, our findings can be used as base data to do a further study of finding and developing more stable storage conditions of the soybean flour.

• Restorative Dentistry and Endodontics
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• v.21 no.1
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• pp.19-34
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• 1996

It has been demonstrated that intracoronal bleaching of pulpless teeth may result in cervical root resorption. Several authors postulated that bleaching agents such as hydrogen peroxide penetrated through the dentinal tubules to damage the surrounding tissues that cause cervical root resorption. The purpose of this study was to suggest on in vitro model for direct determination of hydrogen peroxide penetration through CEJ during nonvital bleaching. In addition, this model permit the quantification of the amount of hydrogen peroxide penetrated during the procedure. Freshly extracted intact premolars, removed for orthodontic reasons were used. Root canal treatment was performed in each tooth. And then the outer surface and crown portion of the teeth was sealed with wax leaving the CEJ. The prepared teeth mounted on the wax laminates were placed in plastic assay tubes containing 1.5ml bidistilled water with their entire root, including the CEJ, submerged in the solution. The teeth were dividied into four groups. Thermo group : thermocatalytic bleaching with superoxol Walk group: walking bleaching with sodium perborate & superoxol Combi group : combination of thermocatalytic & walking bleaching Dw group : walking bleaching with sodium perborate & water The bleaching procedure was performed three times. The bleaching intervals were at 3 days. The hydrogen peroxide present in the assay system was added to ferrous ammonium sulfate resulting in ferric ion release. Upon the addition of potassium thiocyanate a ferrithiocyanate complex results, which absorbs light at the wavelength of 467nm. The radicular penetration of hydrogen peroxide in the four groups was assessed directly using spectrophotometer. The amount of hydrogen peroxide in the samples tested is determined by comparing them with a standard curve generated by known amounts of hydrogen peroxide. The results were obtained as follows : 1. In all experimental groups except the Dw group showed lower penetration amount in day 4 than day 1, there was statistical importance in the difference (P<0.05). 2. After 3rd treatment, Thermo group showed slightly increased value and narrow distribution. Walk group showed much more penetration amount and widely dispersed value. Value of Combi group showed wide distribution without regard to treatment time, but value of Dw group evenly distributed. 3. Thermo group, Walk group and Dw group showed a tendency of increasing penetration amount with increasing treatment times(P<0.01), but Combi group revealed no statistically important differences. 4. Combi group showed the highest degree of penetration. Walk group showed lower penetration than Combi group. Thermo group & Dw group showed lower than Walk group. 5. Cervical root permeability to hydrogen peroxide varied from 0 to 35 %.

• Journal of the Korean Home Economics Association
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• v.24 no.1
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• pp.43-51
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• 1986

In order to study antioxidative acton of garlic, alliin, scordinin, garlic oil, ethanol fraction and non-kaolin fraction which have been discovered from garlic until now were extracted and isolated, and each fraction was utilized as the experimental materials. Antioxidative action of each fraction was compared through the in vitro and in vivo experiments. Electron donatingability on $\alpha$, $\alpha$-diphenyl-$\beta$picrylhydra-$\chi$yl, the inhibitory effect of lipoperoxide formation by TBA and peroxide value were measured and analyzed. RESULTS : 1. When observed antioxidative ability by EDA value, ethanol fraction of garlic components showed the strongest reaction as 15.25. 2. In vitro experiment with TBA value, garlic oil, alliin and ethanol fracton showed distinctive effect on inhibitory effect of lipoperoxide formation. 3. Comparing with the inhibitory effect of lipoperoxide formation with TBA value in vivo, the ethanol fraction was the most effective in the blood or liver by intraperitoneal administration, whereas the ethanol fraction in the blood and non-kaolin fraction in the liver was most effective each other by orally administration. 4. In vitro experiment with peroxide value, garlic oil was distinctive effect on the inhivitory effect of lipoperoxide formation, which was a similar to the trend of TBA value in vitro. 5. Examining the induction time for the first period of lipoperoxide formation in vitro, garlix oil, ethanol fraction and alliin were effective, which was a similar to the trend of TBA value and peroxide value in vitro.

• Food Science of Animal Resources
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• v.32 no.1
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• pp.98-102
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• 2012

The aim of this study was to investigate the relationship between a simple method for measuring lipid peroxidation by using a chemiluminescence analyzer and traditional methods, such as 2-thiobarbituric acid reactive substances or peroxide value of solid food samples. Freeze-dried egg yolk powder was kept on $25^{\circ}C$, under dark condition. The peroxidation value was measured during certain storage period by using 3 methods, and the chemiluminescence value was compared with 2-thiobarbituric acid reactive substances or peroxide value. For comparison, 3 kinds of freeze-dried egg yolk were prepared from whole eggs purchased from a local market. The chemiluminescence value was significantly correlated with both the peroxide value and the 2-thiobarbituric acid related substances during storage, and showed a high correlation to the real sample test. It showed a little higher correlation with peroxide value. These results suggest that using a chemiluminescence analyzer may provide the ability to measure the lipid peroxidation of high lipid content solid-food samples, instead performing both the 2-thiobarbituric acid reactive substances test and measuring the peroxide value.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.09a
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• pp.191-194
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• 2004

The concentration of hydrogen peroxide in soil and effluent was measured to understand the relationship between the profile of hydrogen peroxide and the removal efficiency of phenanthrene in an Electrokinetic-Fenton process. Electrokinetic phenomena were observed in two different conditions for 1, 2, 4, and 7 days; 3.5% and 10% hydrogen peroxide. The concentration of hydrogen peroxide in soil was high near the anode and decreased towards the cathode due to the direction of electroosmosis. The hydrogen peroxide concentration in effluent increased with time, but the value was lower than the initial. The removal efficiency of phenanthrene at 10% hydrogen peroxide was higher than the case at 3.5%. The removal efficiency after 7 days was high(> 97%) in both cases.

• The Korean Journal of Food And Nutrition
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• v.11 no.2
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• pp.137-142
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• 1998

This study aims to examine appropriate kinds of pan oil to release a cake from the pan coated with polyether sulphone and to prove the change of acid value and peroxide value during the process of baking. The major factor effecting the rate of release of the cakes from the pan was properties of the oils rather than the additives. The releasing rate appeared higher as the iodine value was lower. The highest releasing rate was found in the sample, which was made of coconut oil plus 2% of wax, 2% of lecithin. The changes of acid value of the pan oil between the beginning and after baking was little different. In contrast, Peroxide value showed a great change after baking.

• Microbiology and Biotechnology Letters
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• v.9 no.1
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• pp.21-27
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• 1981

The effects of anti-oxidant of ether extract of red pepper peel were studied to compare with butylated hydroxyl toluene (BHT), citric acid and ascorbic acid. Peroxide and acid values of magarine irradiated with the sunlight were detected. The results were as follows: 1. The extract of red pepper peel influenced as antioxidant of magarine. But the extract was lower anti-oxidative effect than that of BHT at the same concentrations. The anti-oxidative effect increased with the concentration of the extract applied. 2. There was no synergistic and anti-oxidative effects, when the extract was used together citric and ascorbic acids. 3. The peroxide value of fermented magarine was controlled by the addition of the extract and BHT. However acid value of it was not controlled as much as peroxide value.

• Restorative Dentistry and Endodontics
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• v.27 no.4
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• pp.441-447
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• 2002

The bleaching of discolored nonvital teeth is conservative treatment that satisfy the cosmetic desire. The most common method for this treatment, walking bleaching, is using 30% hydrogen peroxide and sodium perborate. Many alternatives are suggested for preventing the external cervical root resorption that is the common complication of the nonvital teeth bleaching with 30% hydrogen peroxide The same extent of oxidation reactions as that resulted by the bleaching with the application of 30% hydrogen peroxide and sodium perborate can also be acquired more safely by materials that contain 10% carbamide peroxide, used primarily for the bleaching of vital teeth. Therefore, this study was performed to evaluate the efficacy of 10% and 15% carbamide peroxide bleaching gel in nonvatal teeth bleaching. The internal bleaching of intentionally discolored teeth was performed in vitro with 10% carbamide peroxide (Group 1), 15% carbamide peroxide (Group 2), mixture of distilled water and sodium perborate (Group 3), and mixture of 30% hydrogen peroxide and sodium perborate (Group 4). The bleaching materials were refreshed following 3, 6, 9 and 12 days. To evaluate the bleaching effect, the color change of the crowns was measured at 1, 2, 3, 4, 7 and 15 days of bleaching using the colorimeter. The results were as follows：1. L$^*$ and $\Delta$E$^*$ values were increased with time in all bleaching agents (p<0.01). 2. There was no significant difference in L$^*$ and $\Delta$E$^*$ value among bleaching agents. 3. $\Delta$E$^*$ value higher than 3 was shown after 3 days of bleaching with 10% carbamide peroxide gel, 1 day with 15% carbamide poroxide gel, 4 days with mixture sodium perborate and distilled water and 4 days with mixture sodium perborate and 30% hydrogen peroride, respectively. These results revealed that the use of 10% and 15% carbamide peroxide bleaching gel in non-vital teeth bleaching is as effective as mixture of distilled water and sodium perborate and mixture of 30% hydrogen peroxide and sodium perborate. Accordingly, carbamide peroxide could be used clinically to bleach discolored non-vital teeth.

• Food Science and Biotechnology
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• v.17 no.1
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• pp.85-89
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• 2008

This study was carried out to examine the antioxidant effects of cheonggukjang combined with Phellinus linteus extract. The electron-donating activity (EDA) of cheonggukjang containing 0.3% P. linteus extract (0.3% CPLE) was higher than that of cheonggukjang only. EDA of the ethanol extract from cheonggukjang was higher than that of the water extract. The water and the ethanol extracts showed strong antioxidant activity with regard to peroxide value. However, the ethanol extract showed a higher peroxide value than the water extract. The nitrite scavenging activity of the ethanol extract was greater than that of the water extract, crresponding to the EDA and peroxide values for each extract. Therefore, the antioxidant effects were enhanced by adding 0.3% of extract from P. linteus in manufacturing cheonggukjang. It is suggested that P. linteus extract could be put into practice as an effective antioxidant agent.