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A Study on Remediation of Explosives-Contaminated Soil/Ground Water using Modified Fenton Reaction and Fenton-like Reaction (Modified Fenton Reaction과 Fenton-like Reaction을 이용한 화약류 오염 토양/지하수의 처리에 관한 연구)

  • Hur, Jung-Wook;Seo, Seung-Won;Kim, Min-Kyoung;Kong, Sung-Ho
    • Korean Chemical Engineering Research
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    • v.43 no.1
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    • pp.153-160
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    • 2005
  • There have been large areas of soil contaminated with high levels of explosives. For this experimental work, 2,4,6-trinitrotoluene (TNT) was tested as a representative explosive contaminant of concern in both aqueous and soil samples and its removal was evaluated using three different chemical treatment methods: 1) the classical Fenton reaction which utilizes hydrogen peroxide ($H_2O_2$) and soluble iron at pH less than 3; 2) a modified Fenton reaction which utilizes chelating agents, $H_2O_2$, and soluble iron at pH 7; and 3) a Fenton-like process which utilizes iron minerals instead of soluble iron and $H_2O_2$, generating a hydroxyl radical. Using classic Fenton reaction, 93% of TNT was removed in 20 h at pH 3 (soil spiked with 300 mg/L of TNT, 3% $H_2O_2$ and 1mM Fe(III)), whereas 21% removed at pH 7. The modified Fenton reaction, using nitrilotriacetic acid (NTA), oxalate, ethylenediaminetetraacetic acid (EDTA), acetate and citrate as representative chelating agents, was tested with 3% $H_2O_2$ at pH 7 for 24 h. Results showed the TNT removal in the order of NTA, EDTA, oxalate, citrate and acetate, with the removal efficiency of 87%, 71%, 64%, 46%, and 37%, respectively, suggesting NTA as the most effective chelating agent. The Fenton-like reaction was performed with water contaminated with 100 mg/L TNT and soil contaminated with 300 mg/L TNT, respectively, using 3% $H_2O_2$ and such iron minerals as goethite, magnetite, and hematite. In the goethite-water system, 33% of TNT was removed at pH 3 whereas 28% removed at pH 7. In the magnetite-water system, 40% of TNT was removed at pH 3 whereas 36% removed at pH 7. In the hematite-water system, 40% of TNT was removed at pH 3 whereas 34% removed at pH 7. For further experiments combining the modified Fenton reaction with the Fenton-like reaction, NTA, EDTA, and oxalate were selected with the natural iron minerals, magnetite and hematite at pH 7, based on the results from the modified Fenton reaction. As results, in case magnetite was used, 79%, 59%, and 14% of TNT was removed when NTA, oxalate, and EDTA used, respectively, whereas 73%, 25%, and 19% removed in case of hematite, when NTA, oxalate, and EDTA used, respectively.

Establishment of self-specification and shelf-life by standardization of manufacturing process for lyophilized Tenebrio molitor larvae (동결건조 갈색거저리 유충의 제조공정 표준화에 따른 자가규격 및 유통기한 설정)

  • Chung, Mi Yeon;Lee, Jeong-Yong;Lee, Jin-Chae;Park, Kil-Su;Jeong, Jun-Pyo;Hwang, Jae-Sam;Goo, Tae-Won;Yun, Eun-Young
    • Journal of Sericultural and Entomological Science
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    • v.52 no.1
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    • pp.73-78
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    • 2014
  • This study was carried out to establish the self-specification and shelf-life by standardization of manufacturing process for Tenebrio molitor larvae. First, standardization of manufacturing process for T. molitor was set up. Sterilization for larvae placed on a multistage shelf with intervals of about 10 cm was carried out at $115^{\circ}C$, $1kgf/cm^2$ for 10 min. After sterilization, T. molitor larvae were frozen at less than $-35^{\circ}C$ for more than 12 hrs. And then, they were dried under $-15^{\circ}C$, 0.5 torr vacuum for more than 30 hrs. Second, we decided self-specification for T. molitor larvae. Their moisture, acidity, peroxide, crude protein and crude fat level should be 5% or less, 3 mg/g or less, 30 meq/g or less, 45% or more, and 25% or more, respectively. Also, oleic acid, representative material, level was set up 11 ~ 16%. Third, we decided shelf-life by analysis of the physicochemical characteristic, sensory evaluation and microbial indicators. The final expiry date for lyophilized T. molitor larvae in PET bottle was calculated as 12 months from date of manufacture. We expect that optimal manufacturing process system, self-specification, and shelf-life proposed in this study can be used in industrial production of T. molitor as a novel food.

A Study on Quality Changes of Domestic Frying Oils by Thermal Oxidation (시판식용유의 가열시간에 따른 품질 변화에 관한 연구)

  • Chang, You-Kyung;Lee, Joung-Won;Kim, Teak-Je
    • Korean Journal of Food Science and Technology
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    • v.10 no.2
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    • pp.112-118
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    • 1978
  • Four domestic frying oils (soybean, corn, rapeseed and rice bran oil) were studied on their changing properties according to thermal oxidation by means of chemical analysis of their compositions and measurements of various physical and chemical properties. The content of linoleic acid which is an essential unsaturated fatty acid and the total amount of unsaturated fatty acids were highest in soybean oil (53.2% and 80.3% respectively) among the unheated frying oils and the degree of its thermal degradation was lowest during the continuous heating period for 48 hours at $180^{\circ}C$. However in general, the contents of unsaturated fatty acids were sharply decreased by thermal oxidation whereas the saturated fatty acid contents ranging 10-17% were not changed considerably, which largely agreed with the results of iodine value measurements. The free acid and peroxide values were also lowest in soybean oil (0.09 and 5.6 respectively) among the unheated oils whereas an anomalously high free acid value was observed in rapeseed oil (54.8) which was packed in unleveled glass bottles. Such a high value is probably ascribed to the photo-catalyzed oxidation during storage. The viscosity measurements have shown similar values before heating, but after thermal oxidation for 32 hours the rapeseed and rice bran oils became too thick to measure viscosity by capillary flow method with heavy darkening in color.

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Removal of Odorous Compounds Using Ozone and Hydrogen Peroxide (오존과 과산화수소를 이용한 이취미 물질 산화 제거)

  • Lee, Hwa-Ja;Son, Hee-Jong;Roh, Jae-Soon;Lee, Sang-Won;Ji, Ki-Won;Yu, Pyung-Jong;Kang, Lim-Seog
    • Journal of Korean Society of Environmental Engineers
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    • v.28 no.12
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    • pp.1323-1330
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    • 2006
  • In this study, five different odor causing compounds in the Nakdong river and rapid sand filtered waters were treated by oxidation from $O_3/H_2O_2$ process. In addition, the change in BDOC formation by the $O_3/H_2O_2$ process was also investigated for considering this advanced oxidation Process as a pre-treatment to the BAC treatment process. The experimental result showed that the removal efficiency of geosmin was higher with the use of 5 mg/L of $O_3$ and 0.2 mg/L of $H_2O_2$ than with the use of 20 mg/L of $O_3$ alone for the sand filtered water. And in general, the removal efficiency of geosmin in raw water was $12{\sim}27%$ lower than the one in sand filtered water. In sand filtered water. the removal efficiencies of geosmin and IPMP decreased when $H_2O_2/O_3$ ratio increases above the optimum ratio. The optimum ratio of $H_2O_2/O_3$ dose was $0.5{\sim}1.0$ for geosmin and $0.2{\sim}1.0$ for IPMP. However, the optimum ratio of $H_2O_2/O_3$ in raw water remove geosmin appealed to $1.0{\sim}3.0$. According to the experimental results for the removal of 5 different odor causing compounds under varied $O_3$ doses, the removal efficiency of IPMP was the highest with 60% and, in overall, $O_3/H_2O_2$ process showed higher removal efficiency than $O_3$ alone process. The BDOC formation by the $O_3/H_2O_2$ process increased from $0.1{\sim}0.25$ to $0.19{\sim}0.34$ comparing to $O_3$ process alone. Therefore, it is concluded that the advanced oxidation process with $O_3/H_2O_2$ can be used as a pretreatment to the BAC treatment process.

Studies on the Processing of Low Salt Fermented Sea Foods 4. Processing of Low Salt Fermented Anchovy (저염수산발효식품의 가공에 관한 연구 4. 저염 멸치젓의 가공)

  • CHA Yong-Jun;PARK Hyang-Suk;CHO Soon-Yeong;LEE Eung-Ho
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.16 no.4
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    • pp.363-367
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    • 1983
  • Low salt fermented products of anchovy, Engraulis japonica, caught in the coasts of East Sea of Korea, were prepared tentatively and also discussed the retarding effect of rancidity of the product by the addition of BHA or red pepper. Fresh anchovies were purchased from Kichang fish market. The raw samples were mixed with $8\%$ table salt, $0.5\%$ lactic acid, $6\%$ sorbitol, $4\%$ ethyl alcohol and $0.02\%$ BHA or $0.5\%$ red pepper and filled in the glass bottles and sealed with the cap. Conventional fermented product of anchovy as a control was prepared from fresh anchovy and $20\%$ salt only. After preparation, the products were fermented for 90 days at room temperature. Amino-nitrogen, TBA value, peroxide value and viable counts of bacteria of these products were determined and also evaluation of their qualify was compared with control product by sensory evaluation during fermentation. Amino-nitrogen contents of the low salt products reached a peak in 55 days of fermentation, and the volatile basic nitrogen contents ranged $100\;mg\%$ even after 90 days of fermentation. Thiobarbituric acid value of the product with $0.02\%$ BHA showed a little increase up to 65 days of fermentation regardless of salt contents, while that of the control product increased sharply up to 65 days and then decreased gradually. BHA was effective on retarding rancidity of fermented products of anchovy and red pepper was also slightly effective. All the products showed the highest cell population in about 55 days of fermentation. Judging from the results of analysis and sensory evaluation, the low salt fermented product of anchovy could be prepared with $8\%$ salt, $0.5\%$ lactic acid, $6\%$ sorbitol, $4\%$ ethyl alcohol and $0.02\%$ BHA or $0.5\%$ red pepper to the fresh round anchovy.

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The Effect of Folate Defficiency on Plasma Cholesterol and Antioxidative System in Ethanol-fed Rats (엽산 결핍이 에탄올을 급여한 흰쥐의 체내 콜레스테롤 함량과 항산화계에 미치는 영향)

  • 배민정;양경미;민혜선;서정숙
    • Journal of Nutrition and Health
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    • v.36 no.8
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    • pp.801-810
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    • 2003
  • Chronic alcoholism is considered a common cause of malnutrition. Especially, micronutrient deficiency may playa critical role in the incidence of alcoholic liver diseases. This study was conducted to investigate the effect of folate deficiency and ethanol consumption on cholesterol metabolism and the antioxidative system in rats. Plasma concentration of total cholesterol was increased by ethanol administration in folate-fed rats. HDL-cholesterol tended to be higher in the folate-fed group, but it was not significant. The plasma and hepatic levels of malondialdehyde were increased after chronic ethanol feeding, but dietary folate depressed the plasma malondialdehyde content of rats. Ethanol or folate feeding did not significantly change alcohol dehydrogenase activity. But folate feeding increased catalase activity in ethanol-fed rats. There was no significant change in superoxide dismutase activity among the experimental groups. Glutathione peroxidase activity tended to decrease by chronic ethanol feeding, but dietary folate did not affectthe glutathione peroxidase activity of chronic ethanol-fed rats. Glutathionine-S-transferase activity was not affected by ethanol feeding or folate deficiency. The plasma and hepatic levels of retinol decreased after chronic ethanol feeding. The hepatic level of retinol significantly decreased in ethanol-fed rats by folate deficiency. The plasma level of $\alpha$-tocopherol tended to be low in the folate deficient group with ethanol feeding, but there was no difference among the experimental groups in the hepatic level of $\alpha$-tocopherol. These results demonstrate that chronic ethanol consumption changes the plasma cholesterol metabolism and antioxidative system of rats, and optimal folate feeding in ethanol-fed rats exerts protective effects to some extent.

Effect of Soybean Curd Residue Fermented by Monascus pilosus on the High fat Diet-Induced Obese Mice (Monascus pilosus로 발효시킨 비지의 항비만 효과)

  • Lee, Sang-Il;Lee, Ye-Kyung;Kim, Soon-Dong;Lee, In-Ae;Choi, Jongkeun;Suh, Joo-Won
    • Journal of Applied Biological Chemistry
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    • v.57 no.1
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    • pp.7-15
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    • 2014
  • This study investigated anti-obesity and antioxidant effects of dietary non-fermented soybean crud residue (SCR) and fermented SCR by Monascus pilosus (FSCR) in high-fat induced-obese mice. SCR and FSCR were supplemented with high-fat diet at 2% (wt/wt) dose for 8 weeks. Both SCR and FSCR significantly lowered body weight, epididymal fat weight and weight gain rate compared to high-fat diet control (HC) group and FSCR group showed lowest weight gain rate. In addition, it was observed that serum and hepatic lipid profiles including triglyceride, total cholesterol, LDL-cholesterol and HDL-cholesterol were significantly improved by supplementing SCR or FSCR. Furthermore, SCR and FSCR administration showed increase of glutathione content and decrease of hepatic lipid peroxide content, serum aminotransferase activity, and hepatic xanthine oxidase activity. On the other hand, activities of reactive oxygen species scavenging enzyme such as superoxide dismutase, glutathione S-transferase and glutathione peroxidase in two test groups were higher than those of HC. Lastly, in comparison with SCR, FSCR was more effective in restoring obesity-related biomarkers to normal level in high-diet induced obese mice. In conclusion, the present study indicates that FSCR could have not only anti-obese effects such as inhibition of abdominal fat accumulation, but also protective effects of cardiovascular disease such as atherosclerosis by decreasing serum and hepatic lipid contents. Furthermore, these results suggest that experimental diets in this study could alleviate hepatic damage caused by overproduction of reactive oxygen spices (ROS) due to obesity via inhibition of ROS generating activities and induction of ROS scavenging activities.

Study on Role of Platelet Aggregation in Cerebrovascular Disease (뇌졸중증(腦卒中症)에 있어서 혈소판(血少板) 응집( 凝集)의 역할에 관한 연구(硏究))

  • Hong, Ki-Whan;Lee, Won-Suk
    • The Korean Journal of Pharmacology
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    • v.18 no.2
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    • pp.15-25
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    • 1982
  • It was undertake to investigate the factors involved in the micro thrombus formation in the plasma from the patients with cerebrovascular disease(CVD) and the in vitro actions of sodium nitroprusside on the platelet aggregate formation. 1) The microthrombus formation in the plasma from CVD was significantly enhanced, in comparison with that from the healthy volunteers. 2) Both lipid peroxide and cathepsin D in the plasma from CVD were higher than those levels from the healthy volunteers. 3) Whereas the platelets from healthy individuals showed less aggregation activity in response to ADP in the second phase those from CVD revealed the enhanced aggregating response to ADP. 4) When the bovine basilar artery, rabbit aorta and human umbilical artery were pretreated with $K^+-free$ PSS, ouabain, 13-hydroperoxylinoleic acid(13-HPLA) and cadmium they markedly enhanced the platelet aggregability respectively. 5) Platelet aggregation induced by $K^+-free$ PSS-treated bovine basilar artery was decreased by sodium nitroprusside in a dose-dependent manner, but not by either hydralazine. 6) Both dibutyryl cyclic AMP and 8-bromo cyclic GMP had the inhibitory action on the platelet aggregation. However, the latter had more prominent action than former. The antiaggregating effect by sodium nitroprusside was antagonized by pretreatment with methylene blue, but not by hemoglobin. These results provide the evidences for the therapeutic use of sodium nitroprusside in the emergency of cerebrovascular disease and in remains the further study of the clinical therapy with it.

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Comparison of Paraquat Actions on Oxygen Radical Generation and Lipid Peroxidation between Submitochondrial Particle and Microsome of Mouse Liver (Paraquat에 의한 산소 Radical 생성 및 지질과산화 작용의 Mouse 간 Submitochondria Particle과 Microsome에서의 비교)

  • Choi, Jung-Hwan;Kim, Yong-Sik;Park, Jong-Hwan;Chung, Myung-Hee;Yunn, Chong-Ku
    • The Korean Journal of Pharmacology
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    • v.27 no.2
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    • pp.155-166
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    • 1991
  • In order to evaluate a potential role of mitochondria in the mediation of toxicity of paraquat (PQ), submitochondrial particle and microsome of mouse liver were compared by oxygen radical generation and lipid peroxidation. With NADH in submitochondrial particle and NADPH in microsome as electron donors, PQ stimulated production of superoxide anion and $H_2O_2$ in both fractions. Under the same conditions, PQ enhanced the generation of ethylene from methional suggestiong stimulation of OH production by PQ. But these effects by PQ were somewhat lower in submitochondrial particle than in microsome. In addition, lipid peroxidation(measured as MDA production) was stimulated by PQ in both fractions. The stimulation of lipid peroxidation in both fractions seemed to occur by the same mechanism probably through perferryl ion. This was supported by the following findings: i) The lipid peroxidation in both fractions was partially inhibited by SOD and completely inhibited by DETAPAC(an iron chelator) but not by catalase or OH scavenger. ii) Addition of $ADP-Fe^{3+}$ further increased PQ-induced lipid peroxidation but decreased ethylene production from methional suggesting no correlation between OH production and lipid peroxidation. The redox-cycling of PQ in mitochondria appeared to be linked to NADH dehydrogenase, not to CoQ since all of the observed stimulations by PQ in submitochondrial particle were inhibited by p-hydroxymercuribenzoate(a NADH dehydrogenase inhibitor) but not affected by other respiratory chain blockers. The above results demonstrate that redox-cycling properties of PQ leading to oxygen radical generation and lipid peroxidation can also occur in mitochondria in the same manner as in microsome. Therefore, the observed actions of PQ in mitochondria suggest that mitochondria may also contribute to toxicity of this drug in vivo.

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Protective Effect of Antioxidants on the Reoxygenation Injury in Hypoxic Myocardium of Rat (저산소 심장의 산소 재공급에 따른 심근 손상에 있어서 항산화제의 보호 효과)

  • Yoon, Hyung-Ku;Lim, Jung-Kyoo;Kim, Myung-Suk
    • The Korean Journal of Pharmacology
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    • v.24 no.1
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    • pp.53-61
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    • 1988
  • The effect of antioxidants on the myocardial cellular damage which occurs during reoxygenation of hypoxic myocardium was examined in isolated rat hearts. The roles of oxygen free radical and lipid peroxidation in reoxygenation injury of myocardium were also investigated. In Langenorff preparation of isolated rat heart, which was made hypoxic by perfusion with the substrate free, hypoxic cardioplegic solution ($37^{\circ}C$, 90 min), the release of cytosolic enzymes (creatine phosphokinase, lactic dehydrogenase) and a lipid peroxidation product, malondialdehyde into the coronary effluent were abruptly increased by reoxygenation. The release of enzymes was closely parallel to that of MDA. These increases of enzymes and lipid peroxidation product were suppressed to various degrees in the presence of scavengers of superoxide anion (superoxide dismutase, 10,000 U), hydrogen peroxide (catalase, 25,000 U) and hydroxyl radical (dimethyl sulfoxide, 10%). A natural antioxidant, ${\alpha}-tocopherol$(4.5 uM) and a synthetic one, butylated hydroxytoluene (2 uM) suppressed the release of cytosolic enzymes with the concomittent reduction of lipid peroxidation as measured by malondialdehyde release into the coronary effluent. These effects of antioxidants were dose dependent, and were more pronounced when the antioxidants were administered throughout hypoxic and reoxygenation periods than given during reoxygenation period only. These results suggest that cytotoxic oxygen free radicals produced in the myocardium during reoxygenation may be responsible fur the myocardial cellular injury by enhancing the lipid peroxidation of cellular membranes. Furthermore, the antioxidants may exert protective effect against reoxygenation damage of hypoxic myocardium through the inhibition of lipid peroxidation reaction.

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