• Title/Summary/Keyword: Plasma Oxidation

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Development of a Gliding Arc Plasma Reforming System to Produce Hydrogen Form Biogas (바이오가스 개질을 위한 글라이딩 아크 플라즈마 개질 시스템 개발)

  • Kim, Seong Cheon;Yang, Yoon Cheol;Chun, Young Nam
    • Applied Chemistry for Engineering
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    • v.20 no.4
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    • pp.423-429
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    • 2009
  • The purpose of this study is to investigate the optimal condition for the hydrogen-rich gas production and the CO removal by reforming of gliding arc plasma reforming system using biogas. The parametric screening studies were carried out according to changes of steam feed amount, catalyst bed temperature in water gas reactor and catalyst bed temperature, input air flow rate in preferential oxidation reactor. The standard condition is as follows. The steam/carbon ratio, catalyst bed temperature, total gas flow rate, input electric power and biogas composition rate ($CH_4$ : $CO_2$) were fixed 3, $700^{\circ}C$, 16 L/min, 2.4 kW and 6 : 4, respectively. The results are as follow, HTS optimum operating conditions were S/C ratio of 3 and reactor temperature of $500^{\circ}C$. LTS were S/C ratio of 2.9 and temperature of $300^{\circ}C$. Also, PROX I optimum conditions were input air flow rate of 300 mL/min and reactor temperature of $190^{\circ}C$. PROX II were 200 mL/min and $190^{\circ}C$ respectively. After having passed through each reactor, the results were as follows: 55% of $H_{2}$ yield, 0% of CO selectivity, 99% of $CH_4$ conversion rate, 27% of $CO_2$ conversion rate, respectively.

Phytosterols content of Keunnunjami germ and its antioxidative effects in adult rats (큰눈자미 배아의 식물성 스테롤 함량 및 성숙기 흰쥐에서 항산화 효과)

  • Liang, Jie;Ma, Jing Wen;Chung, Soo Im;Kang, Mi Young
    • Journal of Nutrition and Health
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    • v.53 no.2
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    • pp.99-110
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    • 2020
  • Purpose: The rice germ fraction is a better source of protein, lipid, and fiber than the rice endosperm. Furthermore, the rice germ is rich in bioactive phytochemicals such as γ-aminobutyric acid, tocopherols, tocotrienols, phytic acid, and so on. In this study, the phytosterol content and antioxidant activity of Keunnunjami germ (KG) or normal rice germ supplement were investigated in healthy adult rats. Methods: In vitro, quantitative assessment of phytosterols, including β-sitosterol, campesterol, cycloartenol, and stigmasterol, was performed. Comparative antioxidant activities of 2 rice germs were measured based on DPPH radical scavenging activity, reducing power, and ABTS radical scavenging capacity. In vivo, male Spraque-Dawley rats (30-weeks-old) were randomly assigned a diet of normal control (NC, AIN-93M diet), AIN-93M diet supplemented with normal rice germ 3% (NG3), or AIN-93M diet supplemented with KG 3% (KG3) and fed for 8 weeks. Results: KG contained significantly higher campesterol and stigmasterol contents and antioxidant activity than normal rice germ. The KG3 group exhibited significantly lower body weight gain as well as inguinal and total white adipose tissue weights. There were no significant differences in plasma glucose, insulin, C-peptide, or homeostasis model assessment of insulin resistance level among the 3 groups. The plasma tumor necrosis factor-α concentration was significantly lower while leptin, advanced oxidation protein products, and interleukin-6 showed downward trends in the KG3 group. In addition, the superoxide dismutase level of the KG3 group was significantly higher compared to the NC and NG3 groups. Conclusion: This study indicates that KG can be considered as a valuable source of phytosterol components. Lastly, KG has strong antioxidant properties and may have potential to ameliorate elevation of proinflammatory cytokine production with age.

Enzymatic Analysis of Organophosphorus Pesticides Using Cholinesterase Inhibition Activities (Cholinesterase 저해 활성을 이용한 유기인계 농약의 효소적 분석)

  • Kim, Jung-Ho
    • The Korean Journal of Pesticide Science
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    • v.5 no.1
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    • pp.12-18
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    • 2001
  • The effects of organophosphorus were examined with inhibition of the cholinesterase activity on tile chicken plasma in vivo and in vitro. The cholinesterase activity in chicken plasma determined by tile Ellman mettled was $23{\mu}mol$/min/g protein. After oral administration with 0.2 and 0.5 times of organophosphorus terbufos $LD_{50}$(1.81 mg/kg), cholinesterase activity were inhibited to 36% and 96% of control after 15min in vivo, respectively. After oral administration with 0.2 and 0.5 times of terbufos $LD_{50}$(1.81 mg/kg), then the recovery of cholinesterase activity followed to 99% and 56% of control after 11hr, respectively. Ki of phosphorodithioate and phosphorothioate with P=S was $74{\sim}322\;mole^{-1}min^{-1}$ in vitro. Ki of phosphate and phosphorothiolate with P=O was $13898{\sim}79610\;mole^{-1}min^{-1}$. Toxicology of organophosphorus with P=S was higher than that of organophosphorus with P=S by oxidation. $pI_{50}$ of phosphorodithioate and phosphorothioate with P=S was $21{\sim}102$ mg/L. $pI_{50}$ of phosphate and phosphorothiolate with P=O was $0.519{\sim}0.071$ mg/L. Enzyme-Inhibition method with cholinesterase was the rapid bioassay method to detect the organohpophorus pesticides in vitro.

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Microfabrication of submicron-size hole for potential held emission and near field optical sensor applications (전계방출 및 근접 광센서 응용을 위한 서브 마이크론 aperture의 제작)

  • Lee, J.W.;Park, S.S.;Kim, J.W.;M.Y. Jung;Kim, D.W.
    • Journal of the Korean Vacuum Society
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    • v.9 no.2
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    • pp.99-101
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    • 2000
  • The fabrication of the submicron size hole has been interesting due to the potential application of the near field optical sensor or liquid metal ion source. The 2 micron size dot array was photolithographically patterned. After formation of the V-groove shape by anisotropic KOH etching, dry oxidation at $1000^{\circ}C$ for 600 minutes was followed. In this procedure, the orientation dependent oxide growth was performed to have an etch-mask for dry etching. The reactive ion etching by the inductively coupled plasma (ICP) system was performed in order to etch ~90 nm $SiO_2$ layer at the bottom of the V-groove and to etch the Si at the bottom. The negative ion energy would enhance the anisotropic etching by the $Cl_2$ gas. After etching, the remaining thickness of the oxide on the Si(111) surface was measured to be ~130 nm by scanning electron microscopy. The etched Si aperture can be used for NSOM sensor.

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Inhibition Effect against the Rat Blood Plasma Oxidation of the $Makgeolli$ ($Takju$) Korean Rice Wine (막걸리(탁주)의 쥐 혈장 과산화물 생성 억제효과)

  • Wang, Seung-Jin;Lee, Hyoung-Jae;Cho, Jeong-Yong;Jang, Mi-Young;Park, Keun-Hyung;Moon, Jae-Hak
    • Food Science and Preservation
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    • v.19 no.1
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    • pp.116-122
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    • 2012
  • The antioxidant activities of $makgeolli$ and other alcoholic beverages were compared. Based on the same volume (70 ${\mu}L$ eq.) of the alcoholic beverages, the 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid ammonium salt) (ABTS+) radical-scavenging activities were as follows: whisky > $makgeolli$ crude extract (MCE) > rice wine (RW) > clarified $makgeolli$ (CM) > soju. Based on the same alcohol concentration (6%) of the alcoholic beverages, however, $makgeolli$ showed the highest activity. In addition, based on the same volume (70 ${\mu}L$ eq.), the inhibition effects against the formation of cholesteryl ester hydroperoxide (CE-OOH) were as follows: soju > whisky > RW > MCE > CM. Based on the same alcohol concentration (6%), however, the inhibition effects against the formation of CE-OOH were as follows: RW > MCE > soju > whisky > CM. Therefore, it was suggested that $makgeolli$ may contain radical-scavenging- and metal-ion-chelate-type antioxidants and may increase the antioxidant activity in the blood.

The Effect of Pre-Treatment Methods for the Life Time of the Insoluble Electrodes (불용성 전극의 전처리 방법이 전극의 수명에 미치는 영향)

  • Park, Mi-Jung;Lee, Taek-Soon;Kang, Meea;Han, Chi-Bok
    • Journal of Korean Society of Environmental Engineers
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    • v.38 no.6
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    • pp.291-298
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    • 2016
  • Electrochemical water treatment process as a useful treatment method for the removal of non-degradable matter has been consistently studied for several decades. Key process of electrochemical water treatment are oxidation reaction from an anode and reduction from a cathode. In this study, the effect of pre-treatment methods in the insoluble electrode manufacturing process for the water treatment has been evaluated for the life time of electrode The results of this study showed that pre-treatment methods of a base metal such as surface roughness, clean method and interlayer formation influenced to life time of electrode when the same condition (catalyst electrode layer coating method and material system) was applied for pre-treatment methods. This study was conducted by using $IrO_2/Ti$ electrode In the test of sand-blasting process, an electrode manufactured by using sanding media of different sizes resulted in the most effective electrode life time when the size of alumina was used for $212{\sim}180{\mu}m$ praticle size (#80). The most effective method was considered using arc plasma in the additional roughness control and cleaning process, sputtering method to form Ta type interlayer formation process.

Protective Effect of Rubus crataegifolius Extracts Against Obesity and Non-alcoholic Fatty Liver Disease via Promotion of AMPK/ACC/CPT-1 Pathway in HFD-induced C57BL/6J Obese Mice (HFD 유도 C57BL/6J 비만 mice에서 AMPK/ACC/CPT-1 경로 촉진을 통한 산딸기 추출물의 비만 및 비알코올성 지방간 질환에 대한 보호 효과)

  • Young Ik Lee;Hui Jin Lee;Su Jin Pyo;Yong Hyun Park;Myng Min Lee;Ho-Yong Sohn;Jin Sook Cho
    • Journal of Life Science
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    • v.33 no.12
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    • pp.967-977
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    • 2023
  • Rubus crataegifolius (RC) is a traditional Asian medicinal plant belonging to the Rosaceae family. The fruits of RC are known to prevent adult diseases through antioxidants. In this study, the effects of RC extract (RCex) on obesity and nonalcoholic fatty liver disease (NAFLD) were evaluated in animal models. Twenty-eight male C57BL/6J mice were induced to become obese for 8 weeks and then the extract was orally administered for 8 weeks. RCex reduced body weight, adipose tissue, liver weight. RCex improved biochemical biomarkers including lipid metabolism (alanine aminotransferase (ALT), aspartate aminotransferase (AST), plasma triglyceride (TG), total cholesterol (TC), high-density lipoprotein (HDL) cholesterol and low-density lipoprotein (LDL) cholesterol). The activation of AMP-activated protein kinase (AMPK) reduced the expression of adipogenesis genes (liver × receptor (LXR), sterol regulatory element-binding protein-1c (SREBP-1c), fatty acid synthesis (FAS), acetyl-CoA carboxylase 1 (ACC1) and the effect of enhancing carnitine palmitoyltransferase (CPT) activity by RCex was verified. RCex also influence on plasma production of hormones (adiponectin & leptin) related on energy expenditure and metabolism. In addition, we confirmed that RCex improved glucose intolerance in HFD-induced obese rats. RCex was first demonstrated to have anti-obesity as well as anti-NAFLD effects by regulating fatty acid oxidation and fatty acid synthesis by phosphorylation of AMPK. This suggests that RCex could be a good supplement for the prevention of obesity and related NAFLD.

ATHEROSCLEROSIS, CHOLESTEROL AND EGG - REVIEW -

  • Paik, I.K.;Blair, R.
    • Asian-Australasian Journal of Animal Sciences
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    • v.9 no.1
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    • pp.1-25
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    • 1996
  • The pathogenesis of atherosclerosis can not be summarized as a single process. Lipid infiltration hypothesis and endothelial injury hypothesis have been proposed and investigated. Recent developments show that there are many points of potential interactions between them and that they can actually be regarded as two phases of a single, unifying hypothesis. Among the many risk factors of atherosclerosis, plasma homocysteine and lipoprotein(a) draw a considerable interest because they are independent indicators of atherogenicity. Triglyceride (TG)-rich lipoproteins (chylomicron and VLDL) are not considered to be atherogenic but they are related to the metabolism of HDL cholesterol and indirectly related to coronary heart disease (CHD). LDL can of itself be atherogenic but the oxidative products of this lipoprotein are more detrimental. HDL cholesterol has been considered to be a favorable cholesterol. The so-called 'causalist view' claims that HDL traps excess cholesterol from cellular membranes and transfers it to TG-rich lipoproteins that are subsequently removed by hepatic receptors. In the so-called 'noncausalist view', HDL does not interfere directly with cholesterol deposition in the arterial wall but instead reflects he metabolism of TG-rich lipoproteins and their conversion to atherogenic remnants. Approximately 70-80% of the human population shows an effective feedback control mechanism in cholesterol homeostasis. Type of dietary fat has a significant effect on the lipoprotein cholesterol metabolism and atherosclerosis. Generally, saturated fatty acids elevate and PUFA lower serum cholesterol, whereas MUFA have no specific effect. EPA and DHA inhibit the synthesis of TG, VLDL and LDL, and may have favourable effects on some of the risk factors. Phospholipids, particularly lecithin, have an antiatherosclerotic effect. Essential phospholipids (EPL) may enhance the formation of polyunsaturated cholesteryl ester (CE) which is less sclerotic and more easily dispersed via enhanced hydrolysis of CE in the arterial wall. Also, neutral fecal steroid elimination may be enhanced and cholesterol absorption reduced following EPL treatment. Antioxidants protect lipoproteins from oxidation, and cells from the injury of toxic, oxidized LDL. The rationale for lowering of serum cholesterol is the strong association between elevation of plasma or serum cholesterol and CHD. Cholesterol-lowing, especially LDL cholesterol, to the target level could be achieved using diet and combination of drug therapy. Information on the link between cholesterol and CHD has decreased egg consumption by 16-25%. Some clinical studies have indicated that dietary cholesterol and egg have a significant hypercholesterolemic effect, while others have indicated no effect. These studies differed in the use of purified cholesterol or cholesterol in eggs, in the range of baseline and challenge cholesterol levels, in the quality and quantity of concomitant dietary fat, in the study population demographics and initial serum cholesterol levels, and clinical settings. Cholesterol content of eggs varies to a certain extent depending on the age, breed and diet of hens. However, egg yolk cholesterol level is very resistant to change because of the particular mechanism involved in yolk formation. Egg yolk contains a factor of factors responsible for accelerated cholesterol metabolism and excretion compared with crystalline cholesterol. One of these factors could be egg lecithin. Egg lecithin may not be as effective as soybean lecithin in lowering serum cholesterol level due probably to the differences of fatty acid composition. However, egg lecithin may have positive effects in hypercholesterolemia by increasing serum HDL level and excretion of fecal cholesterol. The association of serum cholesterol with egg consumption has been widely studied. When the basal or control diet contained little or no cholesterol, consumption of 1 or 2 eggs daily increased the concentration of plasma cholesterol, whereas that of the normolipemic persons on a normal diet was not significantly influenced by consuming 2 to 3 eggs daily. At higher levels of egg consumption, the concentration of HDL tends to increase as well as LDL. There exist hyper-and hypo-responders to dietary (egg) cholesterol. Identifying individuals in both categories would be useful from the point of view of nutrition guidelines. Dietary modification of fatty acid composition has been pursued as a viable method of modifying fat composition of eggs and adding value to eggs. In many cases beneficial effects of PUFA enriched eggs have been demonstrated. Generally, consumption of n-3 fatty acids enriched eggs lowered the concentration of plasma TG and total cholesterol compared to the consumption of regular eggs. Due to the highly oxidative nature of PUFA, stability of this fat is essential. The implication of hepatic lipid accumulation which was observed in hens fed on fish oils should be explored. Nutritional manipulations, such as supplementation with iodine, inhibitors of cholesterol biosynthesis, garlic products, amino acids and high fibre ingredients, have met a limited success in lowering egg cholesterol.

Comparison of the Effects of Cyclodextrin-Naringin Inclusion Complex with Naringin on Lipid Metabolism in Mice Fed a High-Fat Diet (고지방식이를 섭취한 마우스에서 나린진과 나린진-사이클로텍스트린 포접화합물의 지질대사에 대한 영향 비교)

  • Jeon, Seon-Min;Choi, Myung-Sook
    • Journal of the East Asian Society of Dietary Life
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    • v.20 no.1
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    • pp.20-29
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    • 2010
  • Naringin has antioxidant and antihyperlipidemic properties, however, phenolic compounds including naringin are unstable in the presence of light, heat and oxygen. Beta-cyclodextrin ($\beta$-CD) is a cyclic heptamer composed of seven glucose units that enhances the stability and solubility of molecules through the formation of inclusion complexes. This study was conducted out to compare the effects of CD-naringin (CD-N) inclusion complexes with naringin on lipid metabolism in high fat-fed animals. Male C57BL/6 mice were fed either CD-N (0.048%, w/w) or naringin (N, 0.02%, w/w) in a 20% high-fat (HFC, 15% lard, 5% corn oil, w/w) diet for 10 weeks. Orlistat (Xenical, 0.01%, w/w) was used as a positive control (PC). There were no differences in body weight, food intake, liver and heart weights, plasma triglyceride(TG), leptin, adiponectin, resistin, IL-$1{\beta}$ and IL-6 concentrations, and hepatic $\beta$-oxidation, carnitine palmitoyl transferase(CPT), glucose-6-phosphate dehydrogenase (G6PD) and malic enzyme activities between the HFC and CD-N groups or between the HFC and N groups. However, both CD-naringin and naringin supplementation les to a significant reduction in the epididymal and perirenal white adipose tissue weights, plasma free fatty acid, insulin and blood glucose concentrations, hepatic cholesterol and TG contents and hepatic fatty acid synthase (FAS), phosphatidate phosphohydrolase (PAP) and HMG-CoA reductase activities compared to the HFC group. The plasma HDL-cholesterol concentration was significantly higher in CD-N and N groups than in HF and PC groups. These results indicate that both CD-naringin and naringin supplementation effectively improved plasma and hepatic lipid metabolism without differences between CD-N and naringin groups.

Effects of Arsenite and Antioxidants on Sperm Motility, Plasma Membrane Integrity, Mitochondrial Activity, and Lipid Peroxidation in Pigs (돼지정자의 운동성, 원형질막 온전성, 미토콘드리아 기능성 및 원형질막 지질과산화에 미치는 arsenite 및 항산화제의 영향)

  • Kim, Han-Su;Lee, Yu-Sub;Lee, Sang-Hee;Cheong, Hee-Tae;Park, Choon-Keun;Lee, Seunghyung;Yang, Boo-Keun
    • Journal of Life Science
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    • v.27 no.5
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    • pp.517-523
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    • 2017
  • This study was to investigate the role of antioxidants on the characteristics of arsenite-damaged boar semen. Collected sperm was diluted with semen extender, and $100{\mu}M$ arsenite was used for sperm damage. Then melatonin, silymarin, curcumin, and vitamin E were applied for 3, 6, and 9 hr in arsenite-treated boar sperm. Sperm characteristics were then analyzed for motility, plasma membrane integrity, mitochondrial activity, and lipid peroxidation. In the results, sperm motility (control, $77.3{\pm}1.8%$) was decreased by arsenite ($33.3{\pm}1.5%$), while the antioxidant treatment groups (100 nM melatonin, $55.8{\pm}3.4%$; $2{\mu}M$ silymarin, $48.8{pm}3.4%$; $10{\mu}M$ curcumin, $53.9{\pm}2.8%$; and $500{\mu}M$ vitamin E, $54.5{\pm}3.1%$) showed increases compared to the arsenite group (p<0.05). $100{\mu}M$ arsenite decreased the sperm plasma membrane integrity ($24.5{\pm}1.6%$) and mitochondrial activity ($58.2{\pm}2.6%$), and increased lipid peroxidation ($5.3{\pm}0.2%$) at 3 hr (p<0.05). However, arsenite-treated samples with 100 nM melatonin, $2{\mu}M$ silymarin, $10{\mu}M$ curcumin, and $500{\mu}M$ vitamin E increased the plasma membrane integrity and mitochondria activity, and decreased lipid peroxidation compared to the arsenite-treated samples. In summary, arsenite may induce sperm damage and oxidation stress, while antioxidants such as melatonin, silymarin, curcumin, and vitamin E are useful for maintaining sperm characteristics. Therefore, antioxidants can protect sperm against damage by arsenite in fresh boar semen.