• Environmental Engineering Research
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• 제10권3호
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• pp.138-143
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• 2005

Laboratory batch experiments were conducted to evaluate the Fenton degradation rates of phenanthrene. Fenton reactions for the degradation of phenanthrene were carried out with aqueous and slurry phase, to investigate the effects of sorption of phenanthrene onto solid phase. Various types of surfactants and electrolyte solutions were used to evaluate the effects on the phenanthrene degradation rates by Fenton's reaction. A maximum 90% removal of phenanthrene was achieved in aqueous phase with 0.9% of $H_2O_2$ and 300 mg/L of $Fe^{2+}$ at pH 3. In aqueous phase reaction, inhibitory effects of synthetic surfactants on the removal of phenanthrene were observed, implying that surfactant molecules acted as strong scavenger of hydroxyl radicals. However, use of $carboxymethyl-{\beta}-cyclodextrin$ (CMCD), natural surfactant, showed a slight enhancement in the degradation of phenanthrene. It was considered that reactive radicals formed at ternary complex were located in close proximity to phenanthrene partitioned into CMCD cavities. It was also show that Fenton degradation of phenanthrene were greatly enhanced by addition of NaCl, indicating that potent radical ion ($OCI^-$) played an important role in the phenanthrene degradation, although chloride ion might be acted as scavenger of radicals at low concentrations. Phenanthrene in slurry phase was resistant to Fenton degradation. It might be due to the fact that free radicals were mostly reacting with dissolved species rather than with sorbed phenanthrene. Even though synthetic surfactants were added to increase the phenanthrene concentration in dissolved phase, low degradation efficiency was obtained because of the scavenging of radicals by surfactants molecules. However, use of CMCD in slurry phase, showed a slight enhancement in the phenanthrene degradation. As an alternative, use of Fenton reaction with CMCD could be considered to increase the degradation rates of phenanthrene desorbed from solid phase.

• 한국잠사곤충학회지
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• 제41권3호
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• pp.135-140
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• 1999

This study was designed to investigate the effects of mulberry leaf extract (MLE) on oxygen radicals and their scavenger enzymes in serum of rats. Sprague-Dawley (SD) male rats (160${\pm}$10g) were fed experimental diets (MLE-100 and MLE-300 groups) added 100 and 300mg/kg BW/day for 6weeks. Triglyceride (TG) levels were significantly inhibited (10% and 20%) in MLE-100and MLE-300 groups, but there were no significant differences in total, LDL-and HDL- cholesterol levels in both MLE-100 and MLE-300 groups. Hydroxyl radical ($.$OH) formations resulted in a marked decreases(20∼25%) in MLE-100 and MLE-300 groups compared with control group, while superoxide radical (O2.-)and hydrogen peroxide formations resulted in a considerable decreases(7∼10% and 5∼10%) in MLE-100 and MLE-300 groups compared with control group. Lipid peroxide (LPO)and oxidized protein(>C=O group) productions resulted in a significant decreases (10% and 6∼10%) in MLE-100 and MLE-300 groups compared with control group. Superoxide dismutase (SOD)and catalase (CAT) activities were remarkably increased (30% and 40∼55%) in MLE-100 and MLE-300 groups, but glutathione peroxidase (GSHPX) activities were significantly increased (10∼15%) in MLE-100 and MLE-300 groups compared with control group. These results suggest that anti-aging effect of mulberry leaf extract (MLE) may play a pivotal role in attenuating a various agerelated changes.

• 대한한방부인과학회지
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• 제21권4호
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• pp.69-89
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• 2008

Purpose: This study was performed to evaluate anti-oxidant activities and anti-inflammatory effects of Sungyoutanggagambang(SYTG). Methods: In the study of anti-oxidant activities. SYTG was investigated by DPPH radical scavenger activity. superoxide dismutase activity and superoxide anion radical scavenger activity. In the study of anti-inflammatory effects. SYTG was investigated using cultured cells and murine models. As for the parameters of inflammation. levels of several inflammatory cytokines and chemical mediators which are known to be related to inflammation were measured in mouse lung fibroblast cells(mLFCs) and RAW264.7 cells. Results: Prior to the experiment. we investigated the security of SYTG by measuring GOT and GPT in serum. 1. SYTG showed high antioxidant activity in a concentration-dependent degree by measured scavenging activity of DPPH free radical, superoxide dismutase and superoxide anion radical. 2. SYTG inhibited IL-1$\beta$, IL-6. TNF-$\alpha$, COX-2 and NOS-II mRNA expression as compared with the control group in a concentration-dependent degree in RAW264.7 cell line. 3. SYTG inhibited IL-1$\beta$, IL-6 production significantly at 100 ${\mu}g/ml$ and TNF-$\alpha$ production significantly at 50, 100 ${\mu}g/ml$ as compared with the control group in RA W264.7 cell line. 4. SYTG inhibited IL-1$\beta$, and IL-6 production significantly as compared with the control group in serum of acute inflammation-induced mice. and decreased IL-1$\beta$, IL-6 production in spleen tissue. and also decreased IL-1$\beta$, IL-6 production in liver tissue. Conclusion: These results suggest that SYTG can be useful in treating diverse female diseases caused by inflammation such as endometrosis, myoma, pelvic congestion. chronic cervicitis, chronic pelvic inflammatory disease and so on.

• 한국식생활문화학회지
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• 제34권2호
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• pp.233-239
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• 2019

This paper presents a literature review on the active technologies to regulate the levels of carbon dioxide and oxygen in Kimchi packaging. In this study, laser-etched pouches and $O_2$ scavengers were used for Kimchi packaging, and the efficiency of each packaging technique to regulate the $CO_2$ and $O_2$ levels inside Kimchi packages was investigated. When Kimchi was packaged with a laser-etched pouch, the $CO_2$ concentration in the sample with a high gas transmission rate was less than that in other pouches (p<0.05), and a low $CO_2$ level had little effect on the expansion of the package volume. Kimchi treated with an $O_2$ absorber exhibited a significantly lower (p<0.05) $O_2$ concentration inside the packages relative to the control. A low $O_2$ concentration inside the Kimchi package effectively inhibited the growth of total aerobic bacteria and lactic acid bacteria, as well as yeasts and molds on Kimchi. These results suggest that $O_2$ absorbers have a positive effect on the microbial quality of Kimchi. Therefore, packaging in a laser-etched pouch and the use of an $O_2$ scavenger could provide a novel packaging material for regulating the $CO_2$ and $O_2$ levels during Kimchi packaging.

• Journal of Forest and Environmental Science
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• 제38권1호
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• pp.55-63
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• 2022

The African swine fever virus (ASFV) remains contagious for a long time, not only in the carcass, but also in the bone marrow of an infected animal. The scavenging activity of various animals on ASFV-infected carcasses is a likely risk factor for ASFV transmission. Thus, we conducted this study to determine whether scavengers are potential vectors for ASFV. In nonprotected wild boar carcasses on the forest floor, we investigated the seasonal patterns of carcass decomposition and scavenger visits for feeding on them. The duration from fresh to early skeletonization (only bones and leather remaining) of adult carcasses was 37.6±23.1 days (n=3, range=11-51 days) in winter. The duration from fresh to later skeletonization (only bones and some fur remaining) of all carcasses, including subadult carcasses, was 8.3±2.5 days (n=4, range=7-12 days) in summer. At all three study sites, leopard cats (30.3%), large-billed crows (21.6%), and golden eagles (18.1%) were the frequently visiting species, representing more than 10% of the total visits (343 visits) in winter, whereas raccoons (21.9%), grey-backed thrushes (39.4%), and eyebrowed thrushes (14.7%) were the most frequent visitors in summer. In winter, crows or cinereous vultures were the first animals to arrive at a carcass; in summer, raccoons or crows arrived first. Our results showed that wild boars, raccoons, and leopard cats relatively frequently visited wild boar carcasses and stayed there for a long time. Wild rodents chewing on or staying near carcasses were photographed during winter. In addition to wild boars, thus, mammals, such as raccoons, leopard cats and rodents, and birds, such as accipitrids and thrushes, may be spreaders of ASFV in South Korea.

• Journal of the Korean Wood Science and Technology
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• 제32권1호
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• pp.80-87
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• 2004

천연접착제인 분말상 탄닌수지를 사용한 파티클보드의 물리·기계적 성질의 개선을 위하여 분말상 탄닌수지와 액상 탄닌수지를 혼합하여 사용한 결과, 30:70 (분말 : 액상)의 혼합비가 최적조건이었으며 분말상 탄닌 수지의 비율이 높으면 물성이 저하되는 현상을 볼 수 있었으며 또한 포름알데히드 방산량이 E₀ 수준의 고내수성 제품을 제조할 수 있었다. 한편 요소수지 및 멜라민수지와 분말상 탄닌 수지와의 혼합방법은 물리·기계적 성질의 개선에 영향을 주지 못했으며, 유리포름알데히드 방산에 대한 scavenger의 역할만을 하였다.

• 대한토목학회논문집
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• 제29권2B호
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• pp.207-212
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• 2009

광물촉매에 의한 Fenton 산화에서 모래에 흡착된 phenanthrene을 대표적인 계면활성제인 SDS와 Tween 80을 사용하여 물질이동 영향을 조사하였다. 계면활성제 주입에 따라 액상과 고체상 사이 또는 산화물 표면으로 phenanthrene이 물질이동하였으며, 계면활성제 농도가 증가할수록 phenanthrene의 apparent solubility는 증가하는 경향을 나타내었다. Tween 80은 apparent solubility가 증가 하더라도, 계면활성제가 분해에 scavenger 작용을 하여 모래에 흡착된 phenanthrene 산화에는 영향을 주지 않았다. SDS를 주입하였을 때, Fenton-like 반응에서 SDS와 goethite가 착물을 형성하여 과산화수소 소모량을 지연시켰의며, 계면활성제를 주입 하지 않았을 때 보다 SDS 32 mM를 주입하였을 때 phenanthrene 처리효율이 증가하였다. 그러므로 최적농도의 SDS 주입은 액상과 고체상 사이 또는 산화물 표면에 phenanthrene 산화를 위한 적당한 조건을 제공 해주며, 과산화수소 소모량을 줄이고, phenanthrene 처리효율을 개선시킬 것이다.

• 한국식품영양과학회지
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• 제32권5호
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• pp.733-738
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• 2003

홍화의 식품재로로서 이용성을 높이고자 홍화의 부위별 성분분석 및 DPPH radical소거 활성을 조사하였다. 단백질은 어린싹 부위에 28.39%, 지방은 씨부위에 20.47%로 많이 함유되어 있었다. Glucose는 어린싹에 1253.6 mg%, fructose는 어린싹에 970.7 mg%, sucrose는 꽃봉오리 부위에 912.0 mg%로 많이 함유되어 있었다. Succinic acid는 꽃잎부위에 2795.3 mg%, malic acid는 잎과 어린싹 부위에 각각 2054.8 mg%와 934.2 mg%로 많이 함유하고 있었다. 무기질로는 K이 잎과 어린싹 부위에 각각 2826.8 mg%와 1999.8 mg%, Ca 또한 잎과 어린싹 부위에 각각 2613.6 mg%와 1160.9 mg%로 많이 함유하고 있었다. Llinoleic acid는 어린싹과 씨부위에 각각 80.01%와 78.27%로 가장 많이 함유하고 있었다. 총페놀함량은 꽃잎, 어린싹, 잎 부위에 각각 5.8%, 4.4% 및 2.5%, 총플라보노이드 함량은 꽃잎, 어린싹, 잎 부위에 각각 4.7%, 6.5%및 2.0%로 많이 함유하고 있었다. Serotonin (5-hydroxytryptamine, 5-HT)화합물인 serotonin-I 은 홍화씨 부위에 147.7 mg%, serotonin-II또한 홍화씨 부위에 155.4mg%를 함유하고 있었고, flavonoid화합물인 acacetin도 홍화씨 부위에 116.5 mg%를 함유하고 있었다. 또한, luteolin은 어린싹 부위에 388.3 mg%, luteolin 7-g1ucoside는 잎 부위에 692.3 mg%로 많이 함유하고 있었다. DPPH radical 소거활성은 꽃잎과 잎의 80% 에탄올 추출물이 114.2%와 113.6%의 높은 활성을 나타내어 기존의 합성항산화제인 BHA 100ppm 농도의 88.05%의 활성보다 높은 항산화 활성을 가지고 있음을 확인하였다.

• 한국주조공학회지
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• 제14권6호
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• pp.520-529
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• 1994

This study describes the influence of the trace amount of sulphur on the nucleation behavior of graphite crystals in high purity Fe-C-Si alloys prepared by levitation melting method. Detailed microstructural analyses of high purity(HP) and sulphur added(HP＋S) samples showed that the nucleation of graphite crystals was prevented by sulphur. With decreasing the sulphur content, the shape of graphite crystals tended to spherulitic, and below 2ppm S, that of graphite crystals was only nodular. The critical cooling rate for the nucleation of griphite crystals was calculated as $1.5{\times}10^3k/s$. It is obvious from this work that residual C-C clusters act as an effective nucleation site for graphite crystals and one of the important role of nodularizing elements is to act as scavenger which removes harmful impurities from the solution.

• Journal of Life Science
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• 제10권1호
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• pp.45-47
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• 2000

Nonactin, known as an ionophore antibiotic, was antagonized by the actibity of quercetin, an oxygen radical scavenger. This compound generated superoxide radicals in Bacillus subtilis lysates. A recombination-deficient mutant strain of B. subtilis was more sensitive than a wild strain, and this hypersensitivity was reduced in the presence of dithiothreitol as an antioxidant. These results suggest that superoxide radical is important in the antibacterial action of this agent.