• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.250.2-250.2
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• 2014

Currently, teeth whitening method which is applicable to dental surgery is that physician expertises give medical treatment to teeth directly dealed with a high concentration of hydrogen peroxide and carbamide peroxide. If hydrogen peroxide concentration is too high for treatment of maximized teeth whitening effect [1], it is harmful to the human body [2]. To the maximum effective and no harmful teeth whitening effect in a short period of time at home, we have observed the whitening effect using carbamide peroxide (15%) and a low-temperature atmospheric pressure plasma jet which is regulated by the Food and Drug Administration. The gas supplied conditions of the non-thermal atmospheric pressure plasma jet was with the humidified (0.6%) gas in nitrogen or air at gas flow rate of 1000 sccm. Also, the measurement of chemical species from the jet was carried out using the optical emission spectroscopy (OES), the evidence of increased reactive oxygen species compared to non-humidified plasma jet. We have found that the whitening effect of the plasma is very excellent through this experiment, when bovine teeth are treated in carbamide peroxide (15%) and water vapor (0.2 to 1%). The brightness of whitening teeth was increased up to 2 times longer in the CIE chromaticity coordinates. The colorimetric spectrometer (CM-3500d) can measure color degree of whitening effect.

• Korean Journal of Food Science and Technology
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• v.30 no.5
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• pp.1040-1044
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• 1998

Tetrasodium pyrophosphate peroxidate can be crystallized as a hydrogen-peroxide-bound salt from the solution of tetrasodium pyrophosphate and hydrogen peroxide. The antimicrobial activity and stability of the compound were tested for the use as a food preservative. It showed antimicrobial activities against several food spoilage microorganisms at the concentration of 0.1% (w/v), and was stable for 80 days in room temperature as a form of 70% hydrogen-peroxide-bound tetrasodium pyrophosphate peroxidate. It was also stable at the boiling temperature but decomposed significantly in the presence of metal ions. The compound can be an effective food preservative at the 0.2% (w/v) concentration, which contains 0.03% (v/v) hydrogen peroxide. The compound could be commercialized if the application area and usage direction as well as the removal method of hydrogen peroxide were developed.

• Journal of the Korean Wood Science and Technology
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• v.14 no.3
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• pp.23-29
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• 1986

Alakline peroxide pretreatment for the delignification of poplar wood was performed. sinceit is a simple and efficent method for enhancing the enzymatic digestibility of wood residues. Approximately one-half of their lignin and most of the hemicellulose present in poplar wood were removed when the wood sawdust was reacted at 25$^{\circ}C$ for 100 hrs in an alkaline solution (pH 11.5) of 1% peroxide. The rate of decomposition as well as the saccharification efficiency were enhanced up to 350% and 260% respectively in comparision with those of the controll. This enhancement is comparable with that pretreated with 1% sodium hydroxide and 20% peracetic acid successively. The advantages of alkaline peroxide as delignifying agents against other chemicals were also discussed.

• Journal of fish pathology
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• v.22 no.1
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• pp.1-7
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• 2009

To investigate the effect of hydrogen peroxide in israel carp, Cyprinus carpio, toxicity and microbial activities were determined. For hydrogen peroxide toxicity test, the median lethal concentration ($LC_{50}$) to israel carps Cyprinus carpio (average weight 0.44 g) by acute toxicity was determined after 24 hour treatment. All israel carp were alive in 24 hours treatment at 80 $\mu\ell/\ell$ concentration and $LC_{50}$ value was 148.9 $\mu\ell/\ell$. For biocidal activities of hydrogen peroxide, remove of parasite and growth inhibition of pathogenic bacteria were determined. The parasite Trichodina sp. infected on the skin and gills of israel carps (average weight 0.1 g) was completely eliminated at 40 $\mu\ell/\ell$ of hydrogen peroxide treatment for 24 hour. Most of the minimum inhibitory concentrations (MICs) against 30 fish pathogenic bacteria were less than 40 $\mu\ell/\ell$.

• Journal of Ginseng Research
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• v.23 no.3 s.55
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• pp.176-181
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• 1999

The purpose of this study was to investigate the antioxidant activities of water soluble browning reaction products (WS-BRPs) isolated from korea red ginseng. Antioxidant activities of WS-BRPs were examined with the various systems. All three WS-BRPs (L, S-1 and S-2) were found to have an ability to donate hydrogen to DPPH. Especially, L was more effective than S-1, S-2. and, L as well as S-1 and S-2 was the strongest than BHT, BHA $(5{\times}10^{-4}M),\;{\alpha}-tocopherol\;(1.0{\times}10^{-4})$ and ascorbic acid $(5.7{\times}10^{-3}M)$ previously known as antioxidants. These WS-BRPs (L, S-1 and S-2) also showed a synergistic effect against antioxidative activities of these antioxidants. Moreover S-2 had the strongest activity of these three WS-BRPs to scavenge free radicals such as hydrogen peroxide $(H_2O_2)$.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.27 no.3
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• pp.159-167
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• 2021

The need for biodegradable plastic continues to increase, improvement of physical properties is necessary for actual use in the market. In this study, composite film was produced by adding peroxide additives to bioplastic according to concentration to investigate changes in the melt index, elongation, morphology, and TGA of the composite film. The addition of peroxide compatibilizer showed superior elongation of film and TGA compared to those of control. The added amount of compatibilizer affected the extrusion process, and it was revealed that adding an appropriate amount of peroxidizer is important. Analysis of the composite film's morphology revealed a heterogeneous dispersion sequence due to different rates of crystallization depending on the resin, and surface physical properties were best in the group added with 4% peroxide. The results above showed that the test group added with 4% peroxide compatibilizer was superior in the production of composite biodegradable film.

• Biomedical Science Letters
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• v.28 no.4
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• pp.237-246
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• 2022

Ischemia-reperfusion results in excess reactive oxygen species (ROS) that affect myocardial cell damage. ROS production inhibition is effectively proposed in treating cardiovascular diseases including myocardial hypertrophy. Studies have shown that oxidizing cultured cells in in vitro experiments gradually decreases the permeability of mitochondrial membranes time- and concentration-dependent, resulting in increased mitochondrial membrane damage due to secondary ROS production and cardiolipin loss. However, recent studies have shown that 5-iodo-6-amino-1,2-benzopyrone (INH₂BP), an anticancer and antiviral drug, inhibited peroxynitrite-induced cell damage in in vitro and alleviated partial or overall inflammation in animal experiments. Therefore, in this paper, we studied the preventive effect of INH₂BP on H9c2 cells derived from mouse heart damaged by oxidative stress using 700 μM of hydrogen peroxide. As a result of oxidative stress to H9c2 cells by hydrogen peroxide whether the treatment of INH₂BP or not, hydrogen peroxide caused serious damage in H9c2 cells. These results were confirmed with cell viability and Hoechst 33342 assays. And this damage was through cell death. However, it was confirmed that H9c2 cells pretreated with INH₂BP significantly reduced cell death by hydrogen peroxide. In addition, measurements with DCF-DA assay to determine whether ROS is produced in H9c2 cells treated with only hydrogen peroxide produced ROS significantly, but H9c2 cells pretreated with INH₂BP significantly reduced ROS production by hydrogen peroxide. Taken together, it is believed that INH₂BP can be useful for the prevention and treatment of cardiovascular diseases induced through oxidative stress such as heart damage caused by ischemia/reperfusion.

• The Korean Journal of Pesticide Science
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• v.3 no.3
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• pp.20-26
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• 1999

This study was to investigate the potential degradation of a herbicide paraquat by Fenton reagents(ferric ion and hydrogen peroxide) under UV light irradiation(365 nm) in an aqueous solution. When $10{\sim}500$ mg/L of paraquat was reacted with either ferric ion or hydrogen peroxide in the dark or under UV light, no degradation was occurred. However, the simultaneous application of both ferric ion(0.8 mM) and hydrogen peroxide(0.140 M) in paraquat solution(500 mg/L) caused dramatic degradation of paraquat both in the dark (approximately 78%) and under UV light(approximately 90%). The reaction approached an equilibrium state in 10 hours. In the dark, when $0.2{\sim}0.8$ mM ferric ion was added, $20{\sim}70%$ paraquat of $10{\sim}500$ mg/L was degraded, regardless of hydrogen peroxide concentrations($0.035{\sim}0.140$ M), while under UV light, 95% of 10 and 100 mg/L paraquat was degraded regardless of ferric ion and hydrogen peroxide concentrations. At paraquat concentration of 200 and 500 mg/L, paraquat degradation increased with increasing ferric ion concentrations as in the dark. However the increase in hydrogen peroxide concentration did not affect the extent of paraquat degradation. The initial reaction rate constants(k) for paraquat degradation ranged from 0.0004 to 0.0314, and 0.0023 to 0.0367 in the dark and under UV light, respectively. The initial reaction rate constant increased in proportion to the increase in ferric ion concentration in both conditions. The half-lives of paraquat degradation(t1/2) were 20 - 1,980 and 19 - 303 minutes in the dark and under UV light, respectively. This study indicates that Fenton reagents under UV light irradiation are more potent than in the dark in terms of herbicide paraquat degradation in an aqueous solution.

• Journal of Korean Ophthalmic Optics Society
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• v.1 no.1
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• pp.57-63
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• 1996

The microbial contamination in contact lens care systems and conjunctivas of 40 asymptomatic cosmetic soft contact lens wearers was investigated. Patient ages ranged from 19 to 27(mean:22), most of them have used hydrogel contact lenses for less than 1 year, and the ages of lens cases were 1 weeks ~ 3 months (43 %) or 4~6 months (52%). Twenty-seven patients (67%) chemically disinfected their lenses and 8(20 %) used hydrogen peroxide, and 5 used heat to disinfect. Fourteen patients used commercial non-preserved saline, and 26(65%) were using commercial preserved saline. Sixty-two percent of the patients had bacterial contamination of lens case, and 17% had conjunctival contamination. The bacterial contamination rate was highest in lens cases, followed by unpreserved salines, disinfecting chemicals(non-hydrogen peroxide), and conjunctivas. The fungal contamination rate of cases and conjunctivas was 67% and 15%, respectively, and lens case, unpreserved saline, and conjunctiva seemed more susceptible to contamination. The use of hydrogen peroxide for disinfection rather than chemical disinfection was associated remarkabley with decreased contamination of solution itself, and there was no significant difference in contamination rates between hydrogen peroxide care system and other disinfecting systems. Five of lens cases(13%) and 2 conjunctivas(5%) were contaminated with Pseudomonas aeruginosa, and Candida albicans were isolated from 11cases (27%) and 5 conjunctivas (12%). Of the organisms that were contaminated lens cases and conjunctivas, Pseudomonas aeruginosa, Escherichia coli, Candida albicans, and Aspergillus fumigatus were isolated from lens cases, whereas Pseudomonas aeruginosa, Candida albicans, and Aspergillus fumigatus were recorvered from conjunctivas. Fortunately all of the these tested samples showed 0% of Acanthamoeba in this investigation.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.10
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• pp.1090-1098
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• 2005

Benzoyl peroxide is very toxic to aquatic organisms but environmental concentration or exposure effects were not studied. Distribution of the chemical among multimedia environment was estimated using EQC(Equilibrium Criterion) model based on the physical-chemical properties to evaluate the risk of benzoyl peroxide in environment. Level I describes a situation that 100,000 kg of benzoyl peroxide is emitted into the environment which is equilibrium and steady-state without degradation and advection condition. Level II describes a situation that a constant rate of 1,000kg/h of benzoyl peroxide is continuously discharged into the environment which is equilibrium and steady-state with degradation and advection condition. Level III describes a situation that 1,000 kg/h of benzoyl peroxide is continuously introduced in each air, water, soil, and sediment compartment which are non-equilibrium and steady-state with degradation, advection, and inter-media transfer condition. In Level I and II calculations the chemical was distributed to soil(68.3%) and water(28.7%). In Level III calculation it was primarily distributed to soil(99.9%) and overall residence time was estimated to be 3.4 years. Benzoyl peroxide can be persistent in environment.