• Title/Summary/Keyword: Alkaline Pretreatment

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Effects of NaOH and Humic Acid on the UV Photolysis of PCBs (PCBs의 광화학적 연구: NaOH 및 휴믹산 (humic acid, HA)에 의한 분해특성)

  • Shin, Hae Seung;Kim, Jae Hyoun
    • Journal of Environmental Health Sciences
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    • v.40 no.2
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    • pp.147-156
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    • 2014
  • Objectives: This study was carried out to examine whether the apparent photolysis with or without sensitizers [NaOH and humic acid (HA)] was prompted photodegradation of polychlorinated biphenyl (PCB) in aqueous solution. Methods: PCBs photodegradation occurred using fluorescence black lamps at ${\lambda}_{max}=300nm$. PCB congeners were exposed in 10 ppm HA or 0.05N NaOH solutions, to investigate the decreasing profile of PCB concentration with time. The PCBs were then analyzed by gas chromatography/mass spectrometry (GC-MS). Reductive degradation profile of PCB congeners in the presence of both sensitizers under oxygen-saturated protic conditions was described using the wind-rose diagrams. Results: Use of HA or NaOH decreased PCB concentration with time in the dark and on irradiation, indicating that photolysis underwent through reductive dechlorination through energy transfer and possibly with reactive oxygens. The dechlorination was marked by a chromatographic shift, observed in the GC-MS plots. Therefore it is logical to assume that increasing the dose of sensitizers would increase the photodegradation rates of PCBs. The half-lives of pentachloro-PCB (penta-3) in 0.05N NaOH and 10 ppm HA were estimated at about 47 hours and 39 hours, respectively, under the same experimental conditions of photolysis. It was found that the rate of photolysis of pentachloro-PCB in aqueous solution followed apparent first-order kinetics compared to other congeners. Conclusion: Photochemical degradation (using 328 nm UV light) of penta- and hexa-PCBs in HA or alkaline solution is a viable method for pretreatment method. The results are helpful for the further comprehension of the reaction mechanism for photolytic dechlorination of PCBs in aquatic system.

Effect of Cyclohexane Treatment on Serum Level of Glutathione S-Transferase Activity in Liver Damaged Rats ($CCl_4$ 에 의한 간손상 모델 실험동물에 있어서 cyclohexane 투여가 혈청 glutathione S-transferase 활성에 미치는 영향)

  • 오정대;윤종국
    • Journal of Environmental Health Sciences
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    • v.29 no.2
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    • pp.80-86
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    • 2003
  • To evaluate the effect of cyclohexane(CH) treatment on the serum levels of glutathion S-transferase(GST) activity in liver damaged animals, damaged liver was induced with pretreatment of 50% $CCl_4$ dissolved in olive oil (0.1 m1/100g body weight) intraperitoneally 17 times every other day. To $CCl_4$-treated rats, CH (1.56 g/kg body weight, i.p) was injected once and then the animals were sacrificed at 4 hours after injection of CH. The $CCl_4$-treated animals were identified as severe liver damage on the basis of liver functional findings, 1,e, increased serum levels of alanine aminotransferase(ALT), alkaline phosphate(ALP) and xanthine oxidase(XO) activities. On the other hand, $CCl_4$-treated animals injected with CH once($CCl_4$-pretreated animals) showed more decreased serum levels of ALT and XO, and more increased those of ALP rather than $CCl_4$-treated animals. In case of comparing the GST with ALT activity in liver, both $CCl_4$-treated and pretreated animals showed similar changing pattern of enzyme actvity. Especially $CCl_4$-pretreated animals showed significantly increased serum level of GST actvity compared with the $CCl_4$-treated those, whereas those of ALT showed reversed tendency. In aspects of GST enzyme kinetics, $CCl_4$-pretreated animals showed higher Vmax of liver GST enzyme than $CCl_4$-treated animals. In conclusion, injection of CH to the liver damaged rats led to enhanced liver damage and more increased activity of serum GST which may be chiefly caused by the enzyme induction.

N-acetyl cysteine inhibits H2O2-mediated reduction in the mineralization of MC3T3-E1 cells by down-regulating Nrf2/HO-1 pathway

  • Lee, Daewoo;Kook, Sung-Ho;Ji, Hyeok;Lee, Seung-Ah;Choi, Ki-Choon;Lee, Kyung-Yeol;Lee, Jeong-Chae
    • BMB Reports
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    • v.48 no.11
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    • pp.636-641
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    • 2015
  • There are controversial findings regarding the roles of nuclear factor (erythroid-derived 2)-like 2 (Nrf2)/heme oxygenase-1 (HO-1) pathway on bone metabolism under oxidative stress. We investigated how Nrf2/HO-1 pathway affects osteoblast differentiation of MC3T3-E1 cells in response to hydrogen peroxide (H2O2), N-acetyl cysteine (NAC), or both. Exposing the cells to H2O2 decreased the alkaline phosphatase activity, calcium accumulation, and expression of osteoblast markers, such as osteocalcin and runt-related transcription factor-2. In contrast, H2O2 treatment increased the expression of Nrf2 and HO-1 in the cells. Treatment with hemin, a chemical HO-1 inducer, mimicked the inhibitory effect of H2O2 on osteoblast differentiation by increasing the HO-1 expression and decreasing the osteogenic marker genes. Pretreatment with NAC restored all changes induced by H2O2 to near normal levels in the cells. Collectively, our findings suggest that H2O2-mediated activation of Nrf2/HO-1 pathway negatively regulates the osteoblast differentiation, which is inhibited by NAC.

Silk Dyeing Method in Natural Pigments - In Case of Korean Colored Rice Bran - (한국산 유색미 속겨의 안토시아닌 색소에 의한 견직물염색)

  • 이혜자;유혜자;김정희;이전숙
    • Journal of the Korean Society of Clothing and Textiles
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    • v.26 no.2
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    • pp.263-269
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    • 2002
  • This research was conducted to establish the efficient use of the colored rice bran fur dyeing textiles. To investigate the fabric dyeability of the colored rice bran extract, the anthocyanin pigments were extracted with water of different temperature ranges of 40 ~ 8$0^{\circ}C$ and were dyed on silk fabrics with different dyeing temperature $25^{\circ}C$~6$0^{\circ}C$, at acidic pH and neutral pH, respectively. Aluminum chloride was preheated with mordant K/S value and dyeing fastness of dyed silk fabrics were examined. The anthocyanins of the colored rice bran were stable and red color at acidic pH, red purple or purple blue at neutral pH, but unstable, blue color at alkaline pH. If extracting temperature and dyeing temperature of dyeing solution were higher, the dyeability was high, but the color of dyed fabric showed red tone. When extracting temperature was 8$0^{\circ}C$ and dyeing temperature of dyeing solution was 6$0^{\circ}C$, the dyeability was best. Without mordant, the dyeability of silk fabrics was higher in acidic pH than in neutral pH solution. With mordant, the dyeability was higher than without mordant, and also higher in acidic pH. Pretreatment of aluminum chloride resulted in the increase of color intensity and stability. The laundering fastness of dyed fabrics was good from grade 5 to grade 3-4. Because of the anthocyanins sensitivity on light radiation, the light fastness of dyed fabrics was poor from grade 3 to grade 1-2.

Anti-Oxidative Effects of Rubus coreanum Miquel Extract on Hepatic Injury Induced by Lipopolysaccharide (복분자 추출물이 Lipopolysaccharide로 유도된 간 손상에 대한 항산화 효과)

  • Kim, In-Deok;Kang, Kum-Suk;Kwon, Ryun-Hee;Ha, Bae-Jin
    • Toxicological Research
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    • v.23 no.4
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    • pp.347-352
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    • 2007
  • The protective effects of Rubus coreanum Miquel (RCM) extract against LPS-induced hepatotoxicity were studied in rats. Squrague-Dawley rats were intraperitoneally administered the RCM at 100 mg/kg per day for three weeks. Then single dose of LPS (5 mg/kg) was injected into rats. Four hours later, they were anesthesized with ether and dissected. We examined the levels of glutamate oxaloacetate transaminase (AST), glutamate pyruvate transaminase (ALT), alkaline phosphatase (ALP) and lactate dehydrogenase (LDH) in sera, superoxide dismutase (SOD) in mitochondrial fraction and catalase (CAT), glutathione peroxidase (GPx) in liver homogenate. LPS-treatment markedly increased the levels of AST, ALT, ALP, LDH and significantly decreased those of SOD, CAT and GPx. But RCM-pretreatment decreased the levels of AST, ALT, ALP and LDH by 57.9%, 37.4%, 62% and 69% respectively and increased those of SOD, CAT and GPx by 82.9%, 64.2% and 96.7% respectively. Subsequently, the protective effects of RCM was evaluated through histopathological examination of liver tissue. The LPS treatment increased the state of necrosis and cirrhosis surrounding the central veins (CV) and sinusoid, but RCM-treatment decreased the state of necrosis and cirrhosis in the liver tissue. These results demonstrated that protective effects of RCM against LPS-induced hepatotoxicity.

Effects of Cooling and Exogenous Bovine Somatotropin on Hematological and Biochemical Parameters at Different Stages of Lactation of Crossbred Holstein Friesian Cow in the Tropics

  • Chaiyabutr, N.;Boonsanit, D.;Chanpongsang, S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.24 no.2
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    • pp.230-238
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    • 2011
  • Effects of cooling and supplemental recombinant bovine somatotropin (rbST) on hemato-biochemical characteristics were studied at different stages of lactation of crossbred Holstein Friesian cows in a tropical environment. Ten primiparous cows were divided into two groups of five animals each. The first group was housed as the non-cooled animals in an open-sided barn with a tiled roof in a normal shaded house (NS), while the second group was housed as cooled cows in an open-sided barn with a tiled roof under misty fan cooling (MFC). Three injections with rbST (500 mg per dose) at each stage of lactation (early, mid and late lactation) significantly increased total milk yield as compared with pretreatment in both cooled and non-cooled cows. Milk fat was significantly increased, while total solids, solid not fat, milk protein and lactose were not affected by the rbST treatment. Hematological parameters, plasma proteins, albumin, glucose, triglyceride, cholesterol, creatinine, alkaline phosphatase (ALP), plasma inorganic phosphate and the activities of plasma aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were not affected by supplemental rbST in cooled and non-cooled cows. Supplementation of rbST caused a significant decrease in plasma urea concentration, while plasma FFA concentrations significantly increased in both cooled and non-cooled cows. The results of the present study suggest that exogenous rbST is efficacious in increasing milk yield without adverse effects on lactating crossbred Holstein cows in a tropical environment.

The relation between sewage sludge solubilization and extracellular polymeric substances (하수슬러지 가용화와 체외고분자물질(EPS)간의 관계)

  • Jeon, Byeong-Cheol;Nam, Se-Yong
    • Journal of the Korea Organic Resources Recycling Association
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    • v.27 no.4
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    • pp.43-49
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    • 2019
  • In order to investigate the relation between sewage sludge solubilization and extracellular polymeric substances(EPS) during alkaline-ultrasonic pretreatment, SCOD/TCOD ratio, solubilization rate, VSS/TS ratio, VSS reduction rate, LB-EPS(Loosely-Bound EPS) and TB-EPS(Tightly-Bound EPS) were measured. At the condition of TS 1.0% and pH 12, solubilization rate increased by 27.7%, LB-EPS as Carbohydrate and Protein increased by 14.6 and 13.3 mg/L/g TS, respectively. Withal, VSS decreased by 26.7% and TB-EPS as Carbohydrate and Protein were extracted by 15.7 and 21.9 mg/L/g TS, respectively. Consequently, the concentrations of organic matter and LB-EPS increased and the trends appeared similarly. In addition, the concentrations trend of decreasing solid matter and extracted TB-EPS also appeared similarly.

Separation and Recovery of Iodide in Radioactive Waste for $^129I$ (방사성폐기물 중의 $^129I$ 정량을 위한 요오드의 분리 및 회수)

  • 최계천;한선호;지광용;임석남;박상규
    • Proceedings of the Korean Radioactive Waste Society Conference
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    • 2003.11a
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    • pp.632-635
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    • 2003
  • For the disposal of low-level radwaste from nuclear power plant need the determination of levels of radio nuclides in radwaste. These nuclides include the difficult-to-measure nuclides, so indirect methodology for the determination of the difficult-to-measure nuclides have to be developed. In this work, for the determination of $^129I(t_{1/2}=1.57{\times}10^7 years)$ in low-level radwaste from nuclear power plant is investigated. Recovery of Iodide in simulated waste($UO_2$ pellet) as a soluble and radwaste(resin, woolen fabric)as a insoluble samples are measured. After pretreatment of sample, $I_2$ are extracted from aqueous solution with $CCl_4$. Then I are extracted from $CCl_4$ with 0.1M $NaHSO_3$ aqueous solution. iodide in aqueous solution are determined by ion chromatography. The overall recovery yield is 76.7 (RSD 1.7%) for mixed-acid digestion method. Incase of woolen fabrics, overall recovery yield is 74.3 (RSD 2.2%) and recovery of iodide in resin 56.5(RSD 5.6%) for alkaline fusion method.

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Pretreatment of Feedstock by Ion Exchange Resin Catalyst in Biodiesel process (바이오디젤 공정에서 이온교환수지 촉매에 의한 원료유의 전처리)

  • Lee Soo-Gon;Chae Hee-Jeong;Yoo Jeong-Woo;Kim Eui-Yong
    • KSBB Journal
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    • v.21 no.1 s.96
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    • pp.68-71
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    • 2006
  • Free fatty acids are not esterified by alkaline catalyst transesterification. They are detrimental to the quality specifications in biodiesel. Therefore, we tried to find solid catalyst to remove free fatty acids in feedstock. Amberlyst 15 resin was selected as the best catalyst, and the moisture content containing in the resin was found to be important for the reaction. The removal efficiency of free fatty acids was gradually decreased from 97% to 70% by ten times reuse of resin. In the transesterificaion reaction by KOH catalyst, soap formation could be decreased by 58.3% using the feedstock pretreated by resin. Consequently, the purity of biodiesel was enhanced about 10%, as compared with the non-treated feedstock.

Determination of 4-Methylimidazole and 2-Acetyl-4(5)-tetrahydroxybutylimidazole in Caramel Color and Processed Foods by LC-MS/MS

  • Kim, Tae Rang;Kim, Su Un;Shin, Young;Kim, Ji Young;Lee, Sang Me;Kim, Jung Hun
    • Preventive Nutrition and Food Science
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    • v.18 no.4
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    • pp.263-268
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    • 2013
  • In this study, the quick HPLC-MS/MS method for the simultaneous separation of 2-acetyl-4(5)-tetrahydroxybuthylimidazole (THI) and 4-(5)-methylimidazole (4-MI) in alkaline medium was used for caramel color and processed foods in Korea. After a simple sample pretreatment, 51 4-MI-labeled samples were positive for 4-MI and 2 also contained THI. The concentration of 4-MI was 260.5~24, $499.3{\mu}g/kg$ in caramel color, less than $LOD{\sim}1,712.5{\mu}g/kg$ in sauce, 1,242.3, $5,972.2{\mu}g/kg$ in balsamic vinegar, $2,118.3{\sim}5,802.4{\mu}g/kg$ in complex seasoning, $82.7{\sim}5,110.6{\mu}g/kg$ in curry, and $29.9{\sim}464.4{\mu}g/kg$ in soft drinks. The recovery rate of 4-MI was 97.1~111.0% in sauce and 81.9~110.0% in powder and that of THI was 83.6{\sim}106.4% in sauce and 61.2{\sim}99.4% in powder. Our results concluded a safe amount of 4-MI and THI compared to the limit of Korea additive code but the processed foods do not have a limit of caramel color and 4-MI in Korea. Therefore, research and monitoring of 4-MI and THI is needed for processed foods in Korea.