• Corrosion Science and Technology
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• v.21 no.5
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• pp.412-417
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• 2022

Proton exchange membrane fuel cells (PEMFCs) provide zero emission power sources for electric vehicles and portable electronic devices. Although significant progresses for the widespread application of electrochemical energy technology have been achieved, some drawbacks such as catalytic activity, durability, and high cost of catalysts still remain. Pt-based catalysts are regarded as the most efficient catalysts for sluggish kinetics of oxygen reduction reaction (ORR). However, their prohibitive cost limits the commercialization of PEMFCs. Therefore, we proposed a NiCo@Au core shell structure as Pt-free ORR electrocatalyst in PEMFCs. NiCo alloy was synthesized as core to introduce ionization tendency and autoxidation reaction. Au as a shell was synthesized to prevent oxidation of core NiCo and increase catalytic activity for ORR. Herein, we report the synthesis, characterization, electrochemical properties, and PEMFCs performance of the novel NiCo@Au core-shell as a catalyst for ORR in PEMFCs application. Based on results of this study, possible mechanism for catalytic of autoxidation core@anti-oxidation shell in PEMFCs is suggested.

• Journal of the Korean Applied Science and Technology
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• v.38 no.5
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• pp.1209-1218
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• 2021

The aim of this study was to assure the possiblility of Achyranthes japonica Nakai for a cosmetic material. For this we examined the Anti-oxidation, Anti-inflammation, Anti-wrinkle effects of Achyranthes japonica Nakai extract. Each material is extracted from Achyranthes japonica Nakai roots(AJNR) and Achyranthes japonica Nakai stalks(AJNS) using 70% ethanol. We carried out Nitric oxide assay of the extract with cultured RAW 264.7 macrophage cells, And we conducted MMP-1 assay, Type I procollagen synthesis assay of the extract with cultured CCD-986sk fibroblast cells. After we measured ABTS+ assay and SOD assay of AJNR and AJNS, we knew that effect of anti-oxidant increased as their concentration get higher. The result of this study was that the antioxidant activity of AJNR and AJNS was similarly excellent and the anti-inflammatory activity of AJNR was significantly higher than AJNS. The MMP-1 inhibitory activity and Type I procollagen synthesis of AJNR and AJNS was generally excellent, AJNS had slightly better than AJNR. Therefore I thought it has the chance to play an imfortant role as a functional cosmetic material for anti-oxidant, anti-inflammation and wrinkle reduction effects.

• The Korea Journal of Herbology
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• v.31 no.1
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• pp.69-75
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• 2016

Objectives : The aim of this study is to investigate the various effects of individual or combined extract of GamiSaengmaeksan (GSS) on cell viability, anti-inflammatory and antioxidant activityMethods : In order to evaluate cytotoxicity, MTT assay was performed. We investigated the levels of proinflammatory cytokines such as tumor necrosis factor (TNF)-α and interleukin (IL)-6 and interleukin (IL)-1β, and nitric oxide(NO) in LPS-induced RAW 264.7 cells to check the effects on anti-inflammatory activity. The level of NO production in RAW 264.7 cells was measured by using Griess reagent. The levels of cytokines and ROS were measured by Luminex and Flow cytometry, respectively.Results : At concentration of 200 ㎍/㎖ GSS, cytotoxicity was observed in RAW 264.7 cells. However, at concentration less than 100 ㎍/㎖ of both combine and individual GSS, cytotoxicity was not observed in Raw 264.7 cells. However, the level of ROS in RAW 264.7 cells were decreased at both extract of 100 ㎍/㎖ GSS. Also, the level of NO in RAW 264.7 cells were decreased from extraction of concentration of 100 ug/ml in GSS and individual-extraction of Liriopis Tuber, White Ginseng and Glycyrrhizae Radix. In addition, productions of pro-inflammatory cytokines (TNF-α) in LPS-induced RAW 264.7 cells were decreased from extraction of concentration of 10 and 100 (㎍/㎖) in GSS and individual-extraction of Liriopis Tuber.Conclusions : It is concluded that combined extract of GSS appears to be more effective in anti-oxidation and anti-inflammatory effect than those in individual-extraction of GSS. These results may be developed as a raw material for new therapeutics to ease the symptoms related with inflammatory and oxidative stress.

• Food Science and Preservation
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• v.24 no.5
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• pp.658-665
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• 2017

The current study was performed to investigate the changes of bio-activities of Salicornia europaea (SE) depending on the different dry methods. The ethanol extracts were prepared from the freeze-drying SE (FD), hot-air drying SE (HD), and shade drying SE (SD). Their anti-oxidant and anti-thrombosis activities were compared. The yields of ethanol extraction in FD, HD, and SD were 14.4, 13.2 and 11.9%, respectively. The highest contents of total polyphenol (4.6 mg/g) and total sugar (23.4 mg/g) were shown in FD, whereas, the highest content of reducing sugar (14.6 mg/g) was observed in HD. In anti-oxidation activity assay, the FD and HD showed similar radical scavenging activities and reducing power. However, in SD, nitrite scavenging activity and reducing power were severely decreased. In anti-coagulation activity assay, the thrombin time (TT), prothrombin time (PT) and activated partial thromboplastin time (aPTT) of FD, HD and SD did not show significant changes at 5 mg/mL concentration. But the HD at 7 mg/mL had strong inhibitions against thrombin and blood coagulation factors. The platelet aggregation and hemolysis activities were not affected by dry methods. Our results suggest that both FD and HD are effective to maintain the functional ingredient of SE, and HD is economic and efficient dry process for production of functional food.

• The Journal of Internal Korean Medicine
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• v.39 no.4
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• pp.480-494
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• 2018

Objectives: To investigate the effect of fermented extract of Artemisiae Iwayomogii Herba, Curcumae Longae, Crataegi Fructus and Salviae Miltiorrhizae Radix (FMH) on anti-inflammation associated with dyslipidemia and anti-oxidation in RAW264.7 and HUVEC cells. Methods: The total polyphenols, total flavonoids, DPPH radical scavenging activity, ABTS radical scavenging activity, and cytotoxicity of FMH were measured. RAW264.7 cells treated with FMH were tested for production of NO, and for cytokine and LTB4 levels and HUVEC cells treated with FMH were examined for production of cDNA of genes related to inflammation. Results: 1. FMH contained polyphenols and flavonoids. The DPPH and ABTS radical scavenging activity of FMH increased in a concentration-dependent manner. 2. FMH treatment inhibited the production of nitric oxide (NO), cytokines, and LTB4 in RAW264.7 cell when compared to the untreated control group. 3. FMH decreased the transcription of pro-inflammatory genes, whereas it increased transcription of anti-inflammatory genes, in HUVEC cells. Conclusion: FMH is effective as an antioxidant and for treatment and prevention of dyslipidemia, atherosclerosis, ischemic heart disease, stroke, and other cardiocerebrovascular diseases.

• Ocean and Polar Research
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• v.43 no.3
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• pp.113-126
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• 2021

In the present study, the halophyte C. falcatum extract and its solvent fractions (n-hexane, 85% aqueous methanol, n-butanol, and water) were evaluated for antioxidant and anti-inflammatory activities. Antioxidative ability was measured by DPPH radical, intracellular reactive oxygen species (ROS) and peroxynitrite scavenging, DNA oxidation inhibition, and ferric reducing antioxidant power (FRAP). For DPPH radical and peroxynitrite scavenging, DNA oxidation inhibition, and FRAP, 85% aq.MeOH and n-BuOH fractions showed significant scavenging activity. For production of intracellular ROS in HT-1080 cells, 85% aq.MeOH fraction showed the highest scavenging activity. In addition, anti-inflammatory activity was also assessed by measuring the inhibitory effect against mRNA expression of pro-inflammatory factors (NO, IL-1β, IL-6 and COX-2) in LPS-stimulated Raw 264.7 macrophages. For NO production, crude extract exhibited a strong inhibitory effect at a concentration of 100 ㎍/ml. For mRNA expression of pro-inflammatory cytokines (IL-1β, IL-6, and COX-2), n-BuOH greatly suppressed expression levels of IL-1β and IL-6 at 100 ㎍/ml concentration while 85% aq. MeOH fraction significantly inhibited that of COX-2 even at 100 ㎍/ml. These results suggest that C. falcatum may be used as a potential source for the development of a natural antioxidant or anti-inflammatory agent.

• Food Science and Biotechnology
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• v.17 no.6
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• pp.1228-1234
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• 2008

Having idea to develop more effective anti-diabetic agent from ginseng root, we comprehensively assessed the anti-diabetic activity and mechanisms of ginsam in C57BL/KsJ db/db mice. The db/db mice were divided into 4 groups; diabetic control (DC), ginsam at a dose of 300 or 500 mg/kg (GS300 or GS500) and metformin at a dose of 300 mg/kg (MT300). Ginsam was orally administered for 8 weeks. GS500 reduced the blood glucose concentration and significantly decreased an insulin resistance index. In addition, GS500 reduced the plasma non-esterified fatty acid, triglyceride, and increased high density lipoprotein-cholesterol as well as decreased the hepatic cholesterol and triglyceride. More interestingly, ginsam increased the plasma adiponectin level by 17% compared to diabetic control group. Microarray, quantitative-polymerase chain reaction and enzyme activity results showed that gene and protein expressions associated with glycolysis, gluconeogenesis, and fatty acid oxidation were changed to the way of reducing hepatic glucose production, insulin resistance and enhancing fatty acid $\beta$-oxidation. Ginsam also increased the phosphorylation of AMP-activated protein kinase and glucose transporter expressions in the liver and skeletal muscle, respectively. These changes in gene expression were considered to be the mechanism by which the ginsam exerted the anti-diabetic and anti-dyslipidemic activities in C57BL/KsJ db/db mice.

• Korean Journal of Food Science and Technology
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• v.52 no.3
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• pp.255-262
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• 2020

Obesity is a critical health issue in Korea, where half of all adults are overweight and a third obese. Aronia melanocarpa -rich in flavonoids and phenolics- with antioxidant and anti-inflammatory activities, could have anti-obesity activity and reduce body fat mass by upregulating lipolysis and β-oxidation in obese mice. Male C57BL/6J mice (n=12) were assigned into four groups: normal chow (18% kcal from fat); high-fat diet control (HFD, 45% kcal from fat); HFD+A. melanocarpa (200 mg/kg diet); HFD+Xenical (500 mg/kg diet, positive control). Antioxidant capacity of A. melanocarpa was established in vitro and in vivo. Weight loss was induced as decreased adiposity and lowered respiratory quotient at rest suggested oxidation of stored fat. Adiposity reduction, accompanied with elevated fat utilization, was owing to enhanced activity of hormone-sensitive lipase. Thus, A. melanocarpa lowered adiposity by enhancing lipolysis and utilization of fatty acids in visceral fat.

• Journal of Society of Preventive Korean Medicine
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• v.17 no.3
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• pp.165-176
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• 2013

Objective : The purpose of this study was to establish the simultaneous analysis for six compounds in Gumiganghwal-tang (GMGHT, Jiuweiqianghuo-tang) and to investigate the anti-atherosclerotic effects of GMGHT in vitro. Methods : The column for separation of six compounds was used Luna $C_{18}$ column and maintained at $40^{\circ}C$. The mobile phase for gradient elution consisted of two solvent systems, 1.0% acetic acid in water and 1.0% acetic acid in acetonitrile. The analysis was carried out at a flow rate of 1.0 mL/min with pothodiode array (PDA) detection at 254, 280, and 320 nm. The injection volume was 10 ${\mu}L$. The antioxidant activities of GMGHT were evaluated by measuring free radical scavenging activities on 2,2'-Azinobis-3-ethyl-benzothiazoline-6-sulfonic acid (ABTS) and 1-1-diphenyl-2-picrylhydrazyl (DPPH). The inhibitory effects on low-density lipoprotein (LDL) oxidation were evaluated by the formation of thiobarbituric acid relative substances (TBARS), relative electrophoretic mobility (REM), and fragmentation of apolipoprotein B (ApoB)-100. Results : Calibration curves were acquired with $r^2{\geq}0.9998$. The contents of liquiritin, ferulic acid, baicalin, baicalein, glycyrrhizin, and wogonin in GMGHT were 1.784, 1.693, 37.899, 0.258, 1.869, and 0.034 mg/g, respectively. The GMGHT showed the radical scavenging activity in a dose-dependent manner. The concentration required for 50% reduction ($RC_{50}$) against ABTS and DPPH radicals were 72.51 ${\mu}g/mL$ and 128.49 ${\mu}g/mL$. Furthermore, GMGHT reduced the oxidation properties of LDL induced by $CuSO_4$. Conclusion : HPLC-PDA is considered as an available and convenient method for quality control and standardization of GMGH and GMGHT has potentials on anti-atherosclerosis by anti-oxidative effect and suppressive effect on LDL oxidation.

• IMMUNE NETWORK
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• v.11 no.1
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• pp.42-49
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• 2011

Background: In this study, we have investigated the effect of Korean red ginseng (KRG) extracts on the production of TNF-${\alpha}$ and IL-8 in human keratinocytes. Also, to examine the antioxidative effect of red ginseng extracts, free radical scavenging activity and superoxide dismutase (SOD) activity in human dermal fibroblasts was measured. Methods: To investigate the effect of KRG in atopic dermatitis, we measured the level of TNF-${\alpha}$ and IL-8 secretion in LPS-stimulated human keratinocytes after the treatment of KRG extracts using enzyme-linked immunosorbent assay. Anti-oxidative activity was investigated by measuring 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging and SOD activity. Results: The stimulation of human keratinocytes with KRG extracts shifted the LPS-induced cytokine secretion toward a more immunosuppressive response. KRG dose-dependently decreased TNF-${\alpha}$ and IL-8 production in HaCaT cells and a significant inhibition of TNF-${\alpha}$ was shown when cells were treated with 500 and $1,000{\mu}g/ml$ of KRG extracts. Additionally, KRG extracts showed DPPH radical scavenging and SOD activity in a dose-dependent manner. Particularly, SOD activities of concentrations higher than $60{\mu}g/ml$ of KRG extracts were significantly different in human dermal fibroblast cells. Conclusion: Based on this study, KRG extracts may be a useful immunosuppressive agent in the treatment of atopic dermatitis.