• 한국환경보건학회지
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• 제40권2호
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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.

• 한국환경보건학회지
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• 제29권2호
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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.

• BMB Reports
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• 제48권11호
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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.

• 한국의류학회지
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• 제26권2호
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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.

• Toxicological Research
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• 제23권4호
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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.

• Asian-Australasian Journal of Animal Sciences
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• 제24권2호
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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.

• 유기물자원화
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• 제27권4호
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• pp.43-49
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• 2019

본 연구는 알칼리·초음파 전처리를 통한 하수슬러지의 가용화 정도를 확인하기 위해 슬러지 가용화율과 VSS 감량화율을 측정하였다. 또한 슬러지 가용화와 EPS간의 관계를 확인하기 위해 LB-EPS(Loosely-Bound EPS), TB-EPS(Tightly-Bound EPS)를 측정하였다. 실험 결과, TS 1.0%, pH 12 조건에서 슬러지 가용화율은 27.7% 증가하였고, LB-EPS as Carbohydrate와 Protein은 각각 14.6, 13.3 mg/L/g TS가 증가하여 가용화에 따른 유기물의 변화와 유사한 경향을 나타내었다. 또한 VSS는 26.7% 감량되었고, TB-EPS as Carbohydrate와 Protein은 각각 15.7, 21.9 mg/L/g TS 용출되어 가용화에 따른 고형물의 변화 역시 유사한 경향을 나타내었다.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2003년도 가을 학술논문집
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• pp.632-635
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• 2003

원자력 발전소에서 배출되고 있는 방사성 폐기물의 운반 및 처분과 관련하여 규제가 예상되는 대상 핵종을 선정하고, 특히 방사능 계측기로 직접 측정이 불가능한 드럼 내 방출핵종에${\alpha}{\cdot}{\beta}$ 대한 농도 예측과 검증방법에 관한 연구가 진행되고 있다. 본 연구에서는 $\beta$방출 핵종이면서 반감기가 매우 긴 $^129I(t_{1/2}=1.57{\times}10^7)$의 정량을 위하여 모의 폐기물 중에 함유되어 있는 요오드의 분리 및 회수율을 측정하였다. 모의 폐기물중 가용성 및 난용성 시료의 전처리 방법으로 혼합산 분해법과 알칼리 용융방법을 각각 이용하였으며 두 방법에 대한 요오드의 회수율을 비교하였다. 요오드의 측정방법으로 이온 크로마토그라피를 이용하였으며 매질의 음이온성분에 의한 영향은 없었다. 두 방법의 전체 공정에서 혼합산분해에 의한 요오드의 회수율은 76.7 (RSD 1.7%)이고 알칼리용융에 의한 방법에서 모직물의 경우에는 74.3(RSD 2.2%)이고 Resin의 경우 56.5(5.6%)로 각각 나타났다.

• KSBB Journal
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• 제21권1호
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• pp.68-71
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• 2006

유리지방산은 염기촉매에 의해 바이오디젤로 전환이 되지 않기 때문에 바이오디젤 제품의 질을 저하시키는 원인이 된다. 따라서 본 연구에서는 원료유 중에 존재하는 유리지방산을 제거할 수 있는 고체 촉매를 찾고자 하였다. Amberlyst 15 수지가 최상의 촉매였으며, 수지 내 수분의 함량이 반응에 큰 영향을 주었다. 10회까지 수지를 반복하여 사용한 결과 유리지방산의 제거율이 97%로부터 70%까지 점차적으로 감소하였다. KOH에 의한 바이오디젤 생성반응에서 수지로 전처리한 원료유를 사용하게 되면 전처리하지 않은 원료유를 사용했을 때 비하여 58.3%까지 비누의 생성을 줄일 수 있었으며, 결과적으로 바이오디젤의 순도를 약 10% 향상시킬 수 있었다.

• Preventive Nutrition and Food Science
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• 제18권4호
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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.