• 동의생리병리학회지
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• 제36권6호
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• pp.209-212
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• 2022

We recently reported that Gastrodia elata extracts (GEE) had an effects to protect against lipopolysaccharide-induced cognitive impairment in vivo model. In this study, we investigated the neuroprotective effects and the mechanism of action of GEE in hydrogen peroxide (H₂O₂)-induced cell death of SH-SY5Y human neuroblastoma cell. The SH-SY5Y cells were divided into five groups, including control(non-treated group), 100 μM H₂O₂, 100, 200, 500 ㎍/㎖ GEE+ 100 μM H₂O₂ groups. Pre- and co-treatment with GEE prevented cell death induced by 100 μM H₂O₂ for 24 h in SH-SY5Y cells. Our findings also showed that anti-oxidants enzymes (Cu/Zn superoxide dismutase, Mn superoxide dismutase, catalase) were up-regulated by 100 μM H₂O₂. But GEE suppressed H₂O₂-induced anti-oxidants enzymes decrease in a dose-dependent manner. Treatment with GEE also inhibited phosphorylation of eukaryotic initiation factor-2α (eIF-2α) and p38 by H₂O₂. Taken together, the neuroprotective effects of GEE in terms of recovery of antioxidant enzymes expression, down-regulation of eIF-2α and p38 phosphorylation, and inhibition of cell death are associated with reduced oxidative stress in SH-SY5Y cells.

• 한국식품위생안전성학회지
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• 제13권1호
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• pp.1-5
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• 1998

본 연구는 E. coli O157:H7에 대한 LP system(lactoperoxidae/thiocyanate/hydrogen peroxide)의 항균효과를 측정하기 위해 수행되었다. 초기 접종수준($10^{2},\;10^{4},\;10^{7}cfu/ml$), LP의 농도 (10ppm, 20ppm, 30ppm), 배지종류 (TSB, UHT milk, raw milk), 배양온도 ($5^{\circ}C,\;10^{\circ}C,\;15^{\circ}C$) 등에 따라 E. coli O157:H7에 대한 항균효과를 측정, 비교한 결과, 초기 접종수준을 $10^2/ml$으로 하였을 때와 LP의 농도를 10ppm 및 $5^{\circ}C$ 배양에서 항균력이 가장 높게 나타났다.

• 대한한방내과학회지
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• 제21권2호
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• pp.299-308
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• 2000

This study was performed to elucidate the effects of Gokajisilsosiho-Tang(GJST) on the lactic dehydrogenase(LDH) release, cell viability and activity, lipid peroxidation, DNA synthesis and the changes of total protein synthesis and GSH changes in vivo and in vitro in rat cultured hepatocytes from hydrogen peroxide$(H_2O_2)$-induced injury. The GJST extract had not an effect on cytotoxicity in all experimental results. The treatment of GJST extract of $160{\mu}g/ml$, $320{\mu}g/ml$ showed the significant effect to decrease LDH leakage induced by t-BHP in cultured rat hepatocytes. The higher concentration of GJST extract than $160{\mu}g/ml$, showed the inhibitory effect on decreasing cell viability induced by t-BHP. The treatment of t-BHP to rat cultured hepatocytes resulted in a concentration dependent increase in TBARS, in the presence of GJST extract the production of TBARS induced by hydrogen peroxide was inhibited concentration dependently, significantly inhibited at $80{\mu}g/ml$ of GJST extract and above. The GJST extract simutaneously present with t-BHP prevented the loss of total protein and GSH in a concentration dependent manner. These results suggested that GJST extract may play a hepatoprotective role in oxidative damage induced by hydrogen peroxide and a therapeutic potential of inhibiting liver injury.

• The Korean Journal of Physiology and Pharmacology
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• 제21권5호
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• pp.509-518
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• 2017

Glioblastoma multiforme (GBM) is the most common primary intracranial tumor in adults and has poor prognosis. The GBM-specific tumor microenvironment (TME) plays a crucial role in tumor progression, immune escape, local invasion, and metastasis of GBM. Here, we demonstrate that hypoxia, reactive oxygen species (ROS), and differential concentration of glucose influence the expression of cytokines and chemokines, such as IL-6, IL-8, and IP-10, in human glial cell lines. Treatment with cobalt chloride ($CoCl_2$) and hydrogen peroxide ($H_2O_2$) significantly increased the expression levels of IL-6, IL-8, and IP-10 in a dose-dependent manner in CRT-MG and U251-MG astroglioma cells, but not in microglia cells. However, we found strikingly different patterns of expression of cytokines and chemokines between $H_2O_2$-treated CRT-MG cells cultured in low- and high-glucose medium. These results suggest that astroglioma and microglia cells exhibit distinct patterns of cytokine and chemokine expression in response to $CoCl_2$ and $H_2O_2$ treatment, and different concentrations of glucose influence this expression under either hypoxic or oxidant-enriched conditions.

• Bulletin of the Korean Chemical Society
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• 제33권9호
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• pp.3009-3016
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• 2012

This study evaluated the use of iron-impregnated SBA-15 (Fe/SBA-15) as a catalyst for the oxidative degradation of persistent phenol analogues, such as 2-chlorophenol (2-CP), 4-chlorophenol (4-CP), 2-nitrophenol (2-NP), 4-nitrophenol (4-NP) and 2,4,6-trichlorophenol (2,4,6-TCP) in water. The oxidation reactions were carried out with reaction time, concentration of the phenols, amount of the catalysts, reaction temperature, pH of the reaction mixture as the process variables with or without using hydrogen peroxide as the oxidizing agent. The conversion achieved with Fe/SBA-15 at 353 K for 2-CP, 4-CP, 2-NP, 4-NP, 2,4,6-TCP was 80.2, 71.2, 53.1, 62.8, 77.3% in 5h with a reactant to $H_2O_2$ mole ratio of 1:1, and 85.7, 65.8, 61.9, 63.7, 78.1% in the absence of $H_2O_2$, respectively. The reactions followed pseudo first order kinetics. The leachability study indicated that the catalyst released very little iron into water and therefore, the possibility of secondary pollution is negligible.

• 센서학회지
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• 제30권4호
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• pp.229-235
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• 2021

This study presents a simple approach for the assembly of a free-standing conductive electronic nanofilm of single-walled carbon nanotubes (SWNTs) suitable for enzymatic electrochemical biosensors. A large-scale SWNT electronic film was successfully produced by the dialysis of p-Terphenyl-4,4''-dithiol (TPDT)-treated SWNTs. Furthermore, Horseradish peroxidase (HRP) was immobilized on the TPDT-SWNT electronic film, and the enzymatic detection of hydrogen peroxide (H₂O₂) was demonstrated without mediators. The detection of H₂O₂ in the negative potential range (-0.4 V vs. Ag/AgCl) was achieved by direct electron transfer of heme-based enzymes that were immobilized on the TPDT-SWNT electronic film. The SWNT-based biosensor exhibited a wide detection range of H₂O₂ from 10 µM to 10 mM. The HRP-doped SWNT electronic film achieved a high sensitivity of 342 ㎛A/mM·cm² and excellent selectivity against a variety of redox-active interfering substances, such as ascorbic acid, uric acid, and acetaminophen.

• 분석과학
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• 제12권2호
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• pp.125-129
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• 1999

고농도의 과산화수소(10-75%)를 생산현장에서 손쉽게 측정할 수 있는 전극 센서 시스템을 연구하였다. Teflon 전극체는 휴대에 간편하도록 길이 10 cm, 지금 1.5 cm의 봉 형태로 제작하였고, 작업 극으로는 직경 3 mm의 glassy carbon을, 보조전극으로는 내경 5 mm, 외경 9 mm의 흑연을 전극물질로 사용하였다. 과산화수소 산화전위는 0.8 V의 전위를 걸어주었다. 공장에서 생산된 고농도의 과산화수소를 일정 이온강도의 전해질 용액으로 희석해 10% 이하의 농도가 되도록 하면 과산화수소에 첨가된 안정제의 방해작용과 과산화수소의 산화작용으로 인한 전극표면의 변성을 최소화할 수 있었고, 손쉽게 정량적인 측정을 할 수 있었다. 또한 과산화수소 투과막(teflon membrane${\leq}100{\mu}m$)을 입힌 전극을 이용하면 고농도의 과산화수소를 희석하지 않고 재현성 있게 정량할 수 있었다. 반면 투과막을 이용하는 방법을 내부전해질을 자주 교환해야 하는 단점이 있었다.

• 한국식품영양과학회지
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• 제32권3호
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• pp.444-449
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• 2003

To investigate the long term effect of buchu (Chinese chives) diet on ROS formation in the liver and stin tissue of ICR mice, one of control, 2% or 5% buchu-added diet was fed to ICR mice for 12 months. Superoxide anion (O2ㆍ), hydrogen peroxide($H_2O$$_2$) and hydroxyl radical (ㆍOH) contents were measured in cytosol, microsome, mitochondria of liver and skin of mice, respectively. Behu diet showed a significant decrease of superoxide anion, hydrogen peroxide and hydroxyl radical contents in liver and skin tissues compared to control diet, and this effect is especially higer at 5% than at 2% buchu diet level. ICR mice showed an age-dependent increase in ROS contents, while the group fed buchu diet decreased its ROS contents significantly and ROS contents of liver appeared to be 2 fold higher than skin. The results of the present study suggest that antioxidative components and sulfur-compounds in buchu diet appear to be responsible for the inhibition of ROS formation in ICR mice.

• 전기학회논문지
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• 제67권12호
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• pp.1626-1632
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• 2018

In this paper, we describe the fabrication and characterization of a hydrogen peroxide ($H_2O_2$) sensor based on palladium and copper (PdCu) electroplated laser induced graphene (LIG) electrodes. $CO_2$ laser was used to form LIG electrodes on a PI film. This fabrication method allows simple control of the LIG electrode size and shape. The PdCu was electrochemically deposited on the LIG electrodes to improve the electrocatalytic reaction with $H_2O_2$. The electrochemical performance of this sensor was evaluated in terms of selectivity, sensitivity, and linearity. The physical characterization of this sensor was conducted using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS), which confirmed that PdCu was formed on the laser induced graphene electrode. In order to increase the sensor sensitivity, the Pd:Cu ratio of the electroplated PdCu was varied to five different values and the condition of highest amperometric current at an identical of $H_2O_2$ concentration was chosen among them. The resulting amperometric current was highest when the ratio of Pd:Cu was 7:3 and this Pd;Cu ratio was employed in the sensor fabrication. The fabricated PdCu/LIG electrode based $H_2O_2$ sensor exhibited a sensitivity of $139.4{\mu}A/mM{\cdot}cm^2$, a broad linear range between 0 mM and 16 mM of $H_2O_2$ concentrations at applied potential of -0.15 V, and high reproducibility (RSD = 2.6%). The selectivity of the fabricated sensors was also evaluated by applying ascorbic acid, glucose, and lactose separately onto the sensor in order to see if the sensor ourput is affected by one of them and the sensor output was not affected. In conclusion, the proposed PdCu/LIG electrode based $H_2O_2$ sensor seems to be suitable $H_2O_2$ sensor in various applications.

• The Korean Journal of Ecology
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• 제26권3호
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• pp.115-121
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• 2003

Leaves of two-week old seedlings of tomato (Lycopersicon esculentum) were treated with various concentrations (0∼100 M) of $CdCl_2$ for up to 9 days and subsequent growth of seedlings, symptoms of oxidative stress and isozyme activities of antioxidant enzymes including superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX) and peroxidase (POX) were investigated. Compared with the non-treated control, Cd exposure decreased biomass but increased Cd accumulation, hydrogen peroxide production and lipid peroxidation as malondialdehyde (MDA) formation in leaves and roots. Further studies on the developmental changes of isozyme activities showed that Fe-SOD, Cu/Zn-SOD and one of three APX isozymes decreased and CAT and one of four POX isozymes increased in leaves, whereas Fe-SOD, one of three POX isozymes and two of four APX isozymes decreased and CAT increased in roots, showing different expression of isozymes in leaves and roots with Cd exposure level and time. Based on our results, we suggest that the reduction of seedling growth by Cd exposure is the oxidative stress resulting from the over production of $H_2O_2$ and the insufficient activities of antioxidant enzymes particularly involved in the scavenging of $H_2O_2$. Further, the decreased activities of SOD and APX isozymes of chloroplast origin, the increased activities of CAT and POX and high $H_2O_2$ contents with Cd exposure might indicate that Cd-induced oxidative stress starts outside chloroplast.