• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.24 no.2
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• pp.131-135
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• 2011

We have been studied the effects of oxidant on the properties of Sr-ferrite magnets using mill scale for motor. The small-added (0.5 wt%) $NaNO_3$ oxidant improved significantly the degree of oxidation and the grindability of mill scale, and then highly enhanced the magnetic properties of anisotropic Sr-ferrite sintered magnets; such as the remanent flux density from 3.55 to 3.80 kG, the intrinsic coercivity from 2.75 to 3.22 kOe, and the maximum energy product from 2.90 to 3.45 MGOe.

• Applied Science and Convergence Technology
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• v.26 no.6
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• pp.218-222
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• 2017

This study was conducted to remove $NO_x$, which is the main cause of fine dust and air pollution as well as acid rain. $NO_x$ was tested using 3% NO (diluted in He) as a simulated gas. Experiments were sequentially carried out by oxidizing NO to $NO_2$ and absorbing $NO_2$. Especially, we focused on the changes of NO oxidation according to both oxidant ($NaClO_2$) concentration change (1~10 M) and oxidant pH change (pH = 1~5) by adding HCl. In addition, we tried to suggest a method to improve $NO_2$ absorption by conducting $NO_2$ reduction reaction with reducing agent (NaOH) concentration (40~60%). It was found that NO removal efficiency increased as both concentration of oxidant and flow rate of NO gas increased, and NO decreased more effectively as the pH of hydrochloric acid added to the oxidant was lower. The $NO_2$ adsorption was also better with increasing NaOH concentration, but the NO removal efficiency was ~20% lower than that of the selective NO reduction. Indeed, this experimental method is expected to be a new method that can be applied to the capture and removal of fine dust caused by air pollution because it is a method that can easily remove NO gas by a simple device without expensive giant equipment.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07a
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• pp.82-85
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• 2002

High-quality Sr-ferrite sintered magnets have been studied by using mill scale added SrCO$_3$ and oxidents before oxidation process. The pre-added SrCO$_3$ powders were improved the degree of oxidation and crush of mill scale and the magnetic properties of Sr-ferrite sintered magnets. The small added NaNO$_3$ oxidant was also highly improved the degree of oxidation and crush of mill scale and the magnetic properties of Sr-ferrite sintered magnets; 3805 G of remanent flux density, 3240 Oe of intrinsic coercivity, and 3.45 MGOe of maximum energy product.

• Korean Journal of Pharmacognosy
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• v.39 no.2
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• pp.150-154
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• 2008

Butein is a one of polyphenolic compound widely available in numerous plants. It has broad biological activities including antioxidant and anti-inflammatory activities, which contributed to its protective effects against cancer. Evidences that butein influence proliferation of tumor cells make it important to determine how butein affects cell death of various cancers. In this study, we show that butein, a phenolic compound, induces apoptosis in human T lymphoma jurkat cells. We found that treatment of cells with butein increased apoptosis in a dose- and time- dependent manner as determined by staining cells with Annexin V and 7AAD. There was no significant apoptotic cell death when normal lymphocytes and monocytes from healthy donor were treated with butein. We also found caspase-3 activity was increased during butein-induced apoptosis. The buteininduced apoptotic cell death was blocked by the treatment of cells with caspase-3 inhibitor. These results indicate that butein has the potential to provide an effective strategy against cancer with the advantage of being widely avalible.

• Journal of Environmental Science International
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• v.29 no.11
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• pp.1025-1032
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• 2020

This work was performed to develop a dip injection wet scrubber (DIWS) system with chlorine dioxide as the oxidant. The exhaust pollutants from a lime kiln of paper-mill were introduced to the system. When NaClO₃ was used to oxidize NO into NO₂, the oxidation was unsatisfactory and the combination of HNO₃ or H₂SO₄ was required for 100% oxidation. ClO₂ is recommended to oxidize NO and SO₂ effectively. With the combination of 1^st stage of DIWS and ClO₂, 57.1% of NOx and 98% of SO₂ were effectively removed. In the case of 2^nd stage of DIWS and ClO₂, 93.5% of NOx and 99% of SO₂ were removed. The ClO₂+DIWS process was superior to the ClO₂+Scrubber process in terms of investment, running cost and NOx removal efficiency.

• Korean Journal of Agricultural Science
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• v.46 no.3
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• pp.427-437
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• 2019

Oxidative stress and overproduction of free radicals have been reported to be a major pathological hallmark of neurodegenerative diseases. Samultang has been known as a beneficial agent to treat liver disease and cardiovascular diseases. However, the anti-oxidant activities and neuro-protective effects of Samultang against oxidative stress still have not been evaluated yet. The aim of the present study was to investigate the anti-oxidant and protective effects of Samultang and its four herbal plants, Paeonia lactiflora (PL), Ligusticum striatum (LS), Rehmannia glutinosa (RG), and Angelica gigas (AG), in vitro system and in SH-SY5Y neuronal cells. The extracts of Samultang strongly increased the radical scavenging activities of 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl radical (${\cdot}OH$), and nitric oxide (NO) in a concentration-dependent manner. Furthermore, we investigated the protective effects of Samultang on cellular damage against oxidative stress induced by hydrogen peroxide ($H_2O_2$) in SH-SY5Y cells. Treatment with Samultang alleviated the oxidative stress from $H_2O_2$ by increasing the cell viability and decreasing the intracellular reactive oxygen species levels. Based on these results, we further investigated the radical scavenging effects of PL, LS, RG, and AG. In our results, PL had the highest DPPH, ${\cdot}OH$, and NO radical scavenging activities. Thus, PL has a crucial role in Samultang, which has anti-oxidative and neuro-protective effects. The present research suggests that Samultang and PL have protective roles against oxidative stress from $H_2O_2$-induced neuronal cell death.

• Korean Journal of Organic Agriculture
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• v.27 no.4
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• pp.513-528
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• 2019

Coriandrum sativum L., an annual herbaceous plant of Apiaceae family. The present study evaluated the anti-oxidant activities and anti-inflammatory effects of ethanol extracts of C. sativum. The anti-oxidant activities of C. sativum were measured by total contents of polyphenol, flavonoid, DPPH and ABTS radical scavenging and reducing power activity. And anti-inflammatory effects of C. sativum were measured by LPS-induced RAW 264.7 cells. The results showed that the contents of total polyphenol and flavonoid were 76.03 ± 1.36 mg of gallic acid equivalents/g and 182.23 ± 4.32 mg of rutin equivalents/g at concentration 1 mg/mL of C. sativum. The DPPH radical scavenging activity was found to be 52.8% at 500 ㎍/mL. The ABTS radical scavenging activity was shown in 58.3% after exposure to 1,000 ㎍/mL. Reducing power activity was found to be 66.8% at 2,000 ㎍/mL. The inhibitory effect of NO production was found to be 65% concentration 500 ㎍/mL. In the generation quantity of inflammatory cytokines such as TNF-α and IL-1β in cell culture medium, the expression levels of inflammatory proteins in cells were showed decrease with the increase of concentration. Therefore, we suggest that the C. sativum should be a potential source of alternative anti-inflammatory drug with good anti-inflammatory effects.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.4
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• pp.597-605
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• 2020

The diatom Melosira nummuloides is a microalga that is widely distributed in freshwater and seawater is used is used in the production of silicon and fucoxanthin. The objective of this experimental study was to determine the effects of diatom powder on the physiology of olive flounder Paralichthys olivaceus. In four feeding groups consuming 0%, 1%, 2% and 3% diatom powder. After 8 weeks of feeding, we investigated P. olivaceus growth rate, feed efficiency rate, survival rate, anti-oxidant enzyme rate, non-specific immune activity and immune gene expression. The rates of growth rate, feed efficiency rate and survival were significantly higher for olive flounder in all diatom groups than in the control. The results for anti-oxidant enzyme, superoxide dismutase and catalase showed no significance, but glutathione was significant, depending on the concentration of diatom addition. The galectin and lysozymes of immune genes were increased in the control group. Galectin and lysozymes were thought to have increased due to infections by from pathogens during the experiment period. These results suggest that the addition of diatoms to olive flounder diets is effective in enhancing growth rate and innate immunity.

• Korean Journal of Organic Agriculture
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• v.28 no.4
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• pp.659-677
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• 2020

Leonurus japonicus (L. japonicus) Houtt., a biennial plant in the Lamiaceae family is broadly distributed in Asia such as Korea, China, Japan. The aerial part of L. japonicus is used as a traditional medicine to treat uterine disease including dysmenorrhea, amenorrhea, sterility. In this study, we examined the antioxidant and anti-inflammatory effects of L. japonicus ethanol extracts. The antioxidant activity of L. japonicus was measured by total polyphenol and flavonoid content, and DPPH, ABTS scavenging, reducing power activity, and intracellular ROS expression assay. The anti-inflammatory effects were measured by nitric oxide (NO), cytokines (TNF-α and IL-1β) production and inflammatory protein expression in LPS-induced RAW 264.7 cells. Total polyphenol and flavonoid content of L. japonicus were 51.40 ± 0.47 mg of gallic acid equivalents/g and 73.28 ± 0.10 mg of rutin equivalents/g respectively. DPPH, ABTS radical scavenging activity and reducing power activity tended to increase concentration-dependent and treatment L. japonicus with 400 ㎍/mL reduced ROS production by 69.5%. Furthermore, L. japonicus inhibited NO, TNF-α and IL-1β production in a concentration-dependant manner and reduced the expression levels of inflammatory proteins via regulating NF-κB, MAPK pathway. Therefore, we suggest that L. japonicus could be a natural antioxidants and medicinal source to treat oxidative stress and inflammation-related disease.

• Journal of Acupuncture Research
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• v.31 no.1
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• pp.131-137
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• 2014

Objectives : This study is to investigate the effects of Acanthopanacis Cortex hot aqueous extract on nitric oxide(NO), prostaglandin E2(PGE2) production and DPPH(1,1-diphenyl-2-picryl hydrazyl) radical scavenging activity in macrophages. Methods : Acanthopanacis Cortex(200 g) was heated at $100^{\circ}C$ with distilled water(2 L) for 4hrs. The extract was filtered and concentrated to 100 ml using a rotary evaporator and was frozen at $-80^{\circ}C$, then was freeze-dried. The RAW 264.7 macrophages were subcultured. In order to evaluate cytotoxicity, MTT assay was performed. Experimental groups were divided into five(control, AC 25, 50, 100 and 200 ${\mu}g/ml$) and we measured cytotoxicity. The concentrations of NO were preprocessed by Griess assay. The RAW 264.7 macrophages was pretreated by 10 ${\mu}g/ml$ LPS and experimental groups were divided into five and we measured NO production. The concentrations of $PGE_2$ were measured by enzyme immunoassay. The RAW 264.7 macrophages was pretreated by 10 ${\mu}g/ml$ LPS. Experimental groups were divided into five and we measured $PGE_2$ production. Antioxidant activity was measured by the DPPH method. experimental groups were divided into four(AC 25, 50, 100 and 200 ${\mu}g/ml$) and we measured DPPH radical scavenging activity. Results : 1. Viability of RAW 264.7 macrophages did not significantly decrease in 25, 50 and 100 ${\mu}g/ml$ Acanthopanacis Cortex hot aqueous extract compared to control group. 2. NO production in LPS-stimulated RAW 264.7 macrophages significantly inhibited in 100, 200 ${\mu}g/ml$ Acanthopanacis Cortex hot aqueous extract compared to control group. 3. $PGE_2$ production in LPS-stimulated RAW 264.7 macrophages significantly inhibited in 100, 200 ${\mu}g/ml$ Acanthopanacis Cortex hot aqueous extract compared to control group. 4. DPPH radical scavenging capability of Acanthopanacis Cortex hot aqueous extract in RAW 264.7 macrophages had the high level in 100, 200 ${\mu}g/ml$. Conclusion : According to the results, Acanthopanacis Cortexx hot aqueous extract has ability to suppress NO, $PGE_2$ production and improve DPPH free radical scavenging activity. So Acanthopanacis Cortex hot aqueous extract may have an anti-inflammation effect and antioxidant activity.