• 한방비만학회지
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• 제20권1호
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• pp.10-19
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• 2020

Objectives: Oxidative stress-mediated neuroinflammation has been supposed as a crucial factor that contributes to the pathogenesis of many neurodegenerative diseases. In this study, we aimed to investigate the protective activity against oxidative stress and neuroinflammation of protocatechuic acid (PA), active phenolic compound from Momordica Charantia. Methods: Protective activity of PA from oxidative stress was performed under in vitro conditions. Our study investigated the protective mechanism of PA from neuroinflammation in cellular system using C6 glial cell. To investigate the improvement the effects on oxidative stress and neuroinflammation, we induced oxidative stress by H₂O₂ (100 μM) stimulation and induced neuroinflammation by treatment with lipopolysaccharide (LPS) (1 ㎍/mL) and interferon-gamma (IFN-γ) (10 ng/mL) in C6 glial cells. Results: PA showed strong radical scavenging effect against 1,1-dipenyl-2-picrylhydrazyl, hydroxy radical (·OH) and nitric oxide (NO). Under oxidative stress treated by H₂O₂, the result showed the increased mRNA expressions of oxidative stress markers such as nuclear factor-kappaB (NF-κB), cyclooxygenase (COX-2) and inducible nitric oxide (iNOS). However, the treatment of PA led to reduced mRNA expressions of NF-κB, COX-2 and iNOS. Moreover, PA attenuated the production of interleukin-6 and scavenged NO generated by both endotoxin LPS and IFN-γ together. Furthermore, it also reduced LPS and IFN-γ-induced mRNA expressions of iNOS and COX-2. Conclusions: In conclusion, our results collectively suggest that PA, phenolic compound of Momordica Charantia, could be a safe anti-oxidant and a promising anti-neuroinflammatory molecule for neurodegenerative diseases.

• 사상체질의학회지
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• 제13권1호
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• pp.51-60
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• 2001

Effects of Taeumjowetang on Lipid Peroxidation by Free Radicals and Oxidative Damage of Hepatocytes by tert-Butyl Hydroperoxide. 1. Purpose The present study was carried out to evaluate the antioxidant effects of Taeumjowetang in vitro. 2. Methods In this study, antioxidant effects of TJT on lipid peroxidation were determined according to the method of TBA. (Abbreviation) TJT : Taeumjowetang, TBA : 2-thiobarbituric acid. 3. Results : 1) TJT inhibited markedly peroxidation of linoleic acid during the autoxidation. 2) TJT inhibited lipid peroxidation induced by hydroxyl radical derived from H2O2-Fe2+ in rat liver homogenate. 3) TJT showed 66% scavenging effect on DPPH radical. 4) TJT exhibited a 25% inhibitory effect on superoxide generation from xanthine-xan thine oxidase system. 5) To investigate the antioxidative effects of TJT on the hepatocytes, cultured normal rat liver cells(Ac2F) were prepared and incubated with or without TJT. After 16~18hr, cells placed in DMEM medium without serum, and then incubated with 1mM t-BHP for 2hr. Viable cells were detected by MTT assay. In this test, TJT protected the cell death induced by t-BHP and significantly increased cell viability in the normal rat liver cell. (Abbreviation) DPPH : ${\alpha},{\alpha}$-diphenyl-${\beta}$-picryl hydrazyl, DMEM : Dulbecco's Modified Eagle Medium, t-BHP : terr-butyl hydroperoxide, 4. Conclusion These results suggested that TJT might play a protective role in lipid peroxidation by free radicals.

• Journal of Microbiology
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• 제45권4호
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• pp.318-325
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• 2007

Glucose 6-phosphate dehydrogenase (G6PDH, EC 1.1.1.49) in Deinococcus radiophilus, an extraordinarily UV-resistant bacterium, was investigated to gain insight into its resistance as it was shown to be involved in a scavenging system of superoxide $(O_2^{-1})$ and peroxide $(O_2^{-2})$ generated by UV and oxidative stresses. D. radiophilus possesses two G6PDH isoforms: G6PDH-1 and G6PDH-2, both showing dual coenzyme specificity for NAD and NADP. Both enzymes were detected throughout the growth phase; however, the substantial increase in G6PDH-1 observed at stationary phase or as the results of external oxidative stress indicates that this enzyme is inducible under stressful environmental conditions. The G6PDH-1 and G6PDH-2 were purified 122- and 44-fold (using NADP as cofactor), respectively. The purified G6PDH-1 and G6PDH-2 had the specific activity of 2,890 and 1,033 U/mg protein (using NADP as cofactor) and 3,078 and 1,076 U/mg protein (using NAD as cofactor), respectively. The isoforms also evidenced distinct structures; G6PDH-1 was a tetramer of 35 kDa subunits, whereas G6PDH-2 was a dimer of 60kDa subunits. The pIs of G6PDH-1 and G6PDH-2 were 6.4 and 5.7, respectively. Both G6PDH-1 and G6PDH-2 were inhibited by both ATP and oleic acid, but G6PDH-1 was found to be more susceptible to oleic acid than G6PDH-2. The profound inhibition of both enzymes by ${\beta}-naphthoquinone-4-sulfonic$ acid suggests the involvement of lysine at their active sites. $Cu^{2+}$ was a potent inhibitor to G6PDH-2, but a lesser degree to G6PDH-1. Both G6PDH-1 and G6PDH-2 showed an optimum activity at pH 8.0 and $30^{\circ}C$.

• 생약학회지
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• 제41권3호
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• pp.166-173
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• 2010

Oxidative stress to proteins, lipids, or DNA is higher in human autopsy tissue and in rodent models of a number of neurodegenerative conditions, including Alzheimer's and Parkinson's disease. On the basis of this information, we established a screening system using N18-RE-105 cells to identify therapeutic agents that can protect cells from glutamate toxicity. During the course of our screening program, we recently isolated the active compound 9-hydroxy-$\alpha$-tocopherone ($\alpha$-TP), which prevents glutamate-induced cell death, from Viola mandshurica. The chemical structure of $\alpha$-TP was identified using spectroscopic methods and by comparison with literature values. Antioxidant activity and protective effects of $\alpha$-TP were evaluated by DPPH radical-scavenging assay, morphological assay, MTT reduction assay, and lactate dehydrogenase (LDH) release assay. These results suggest that $\alpha$-TP could be a new potential chemotherapeutic agent against neuronal diseases.

• Toxicological Research
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• 제28권4호
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• pp.241-248
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• 2012

Exposure of cells to ultraviolet B (UVB) radiation can induce production of free radicals and reactive oxygen species (ROS), which damage cellular components. In addition, these agents can stimulate the expression of matrix metalloproteinase (MMP) and decrease collagen synthesis in human skin cells. In this study, we examined the anti-photoaging effects of extracts of Tetraselmis suecica (W-TS). W-TS showed the strongest scavenging activity against 2,2-difenyl-1-picrylhydrazyl (DPPH) and peroxyl radicals, followed by superoxide anions from the xanthine/xanthine oxidase system. We observed that the levels of both intracellular ROS and lipid peroxidation significantly increased in UVB-irradiated human skin fibroblast cells. Furthermore, the activities of enzymatic antioxidants (e.g., superoxide dismutase) and the levels of non-enzymatic antioxidants (e.g., glutathione) significantly decreased in cells. However, W-TS pretreatment, at the maximum tested concentration, significantly decreased intracellular ROS and malondialdehyde (MDA) levels, and increased superoxide dismutase and glutathione levels in the cells. At this same concentration, W-TS did not show cytotoxicity. Type 1 procollagen and MMP-1 released were quantified using RT-PCR techniques. The results showed that W-TS protected type 1 procollagen against UVB-induced depletion in fibroblast cells in a dose-dependent manner via inhibition of UVB-induced MMP-1. Taken together, the results of the study suggest that W-TS effectively inhibits UVB-induced photoaging in skin fibroblasts by its strong anti-oxidant ability.

• 한국식품과학회지
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• 제34권6호
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• pp.1115-1122
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• 2002

시판되고 있는 두류 22 종류의 70% 에탄올 추출물을 제조하여, 이들의 항산화 활성, 화학적 변이원 mitomycin C에 대한 항변이원성, 세포독성, 변이원성 등을 포함하는 생리활성 효과를 비교 검정하였다. DPPH radical에 대한 전자공여능, hydroxy radical 소거능 및 지질 자동산화 억제효과 등은 모든 두류 품종이 거의 유사한 효과를 나타내었다. 예팔, 완두, 녹두, 백편두 등은 변이원 mitomycin C에 대해 유의할만한 수준의 항변이원성을 보였으며, 녹색나물콩, 녹두, 속피리 등은 지시 세포의 성장을 촉진하는 효과가 있었고, 속청과 청태는 변이원성을 억제하는 특성이 있었다. 백편두는 세포 성장과 돌연변이 유발 모두를 억제하는 것으로 나타나 추출물 자체가 독성을 가질 수도 있을 것으로 생각되었다. 결과적으로 본 연구의 목적이었던 기능성 밥 및 떡 제조를 위한 부재료로서의 두류 이용을 위해서는 예팥, 녹두 등을 이용하는 것이 바람직하리라고 생각된다.

• 한국식품영양과학회지
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• 제26권6호
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• pp.1173-1180
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• 1997

Hepatotoxicity of caffeine and acetaminophen was investigated in this study. Special attention was paid to the effect of vitamins on the reduction of hepatotoxicity caused by the chemicals. Rat hepaocytes isolated by two-step perfusion method were cultured in two differents methods-suspension, monolayer cultures-, and exposed to caffeine and/or acetaminophen for 24hrs. Caffeine or acetaminophen exhibited no significant hepatotoxicity in terms of intracellular glutathione(GSH) level and lipid peroxidation(MDA), but GSH level was significantly decreased after administrated acetaminophen, and the toxicity caused by the chemicals showed a dose-dependent manner. The synergistic effect of caffeine and acetaminophen was observed when both caffeine and acetaminophen were supplemented to culture medium. At the concentration 1mM, caffeine enhanced the intracellular GSH depletion and MDA formation by 63% and 64%, respectively, compared to single supplementation of 10mM acetaminophen in culture medium. This hepatotoxicity induced membrane integrity loss was observed by lightmicroscope on the simultaneous administration of caffeine and acetaminophen in monolayer cultured hepatocytes. Co-supplementation of vitamins with caffeine/acetaminophen to culture medium results in the protection of hepatocytes from hepatotoxic attach by caffeine/acetaminophen. Especially, vitamin E was superior to vitamin C and $\beta$-carotene from the standpoints of GSH depletion and MDA formation. From this results, it has been speculated that vitamin E may play a role of antioxidant scavenging radicals produced from acetaminophen. Taken all together, in vitro culture system like monolayer culture of hepatocytes may be a useful tool for the evaluation of hepatotoxicity or protection ability of food ingredients.

• 방사선산업학회지
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• 제5권3호
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• pp.259-266
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• 2011

When plants undergo stress, Reactive oxygen species (ROS) which remove bad elements such as mildew and virus is activated in plant body. However, if ROS is excessively increased, plant will be harmed itself by destruction of cell and signal system and phenomenon of lipid peroxidation. In order to identify content of lipid peroxidation and activity of some enzymes scavenging ROS, phenotypical and physiological analysis was performed with two mutant lines, Till-II-877 and Till-II-894, comparing with cv. Dongan (WT). In phenotype analysis, two mutant lines give to well-conditioned growth better than WT in since 5 days after salt treatment. In enzyme activities, there was a modest difference in the content of catalase (CAT) and peroxidase (POD) between Till-II-877 and Till-II-894, two mutant lines showed high levels in CAT contents than WT. However, they express low levels in POD contents. In MDA analysis, the content of Till-II-877 was higher than that of WT, but Till-II-894 was lower. This result indicates that two mutants have different mechanism against salt stress.

• 약학회지
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• 제52권3호
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• pp.165-171
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• 2008

To develop effective skin whitening agents, we tested natural herbal extracts for their melanogenic inhibitory activities. Sedum samentosum was selected for its inhibitory effect on melanogenesis in B16 melanoma cells. Ethanolic extract of S. samentosum (SSE) was evaluated for antioxidative effect and tyrosinase inhibitory activity of melanogenesis. We investigated the changes in protein level and mRNA level of tyrosinase, tyrosinase related protein (TRP)-1 and TRP-2 by using western blotting and RT-PCR, respectively. SSE showed scavenging activities of free radicals and reactive oxygen species (ROS) with the $IC_{50}$ of 342.7 $\mug/ml$ against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and 64.69 $\mug/ml$ against superoxide radicals in the xanthine/xanthine oxidase system, respectively. SSE treatment suppressed the biosynthesis of melanin up to 46% and reduced tyrosinase activity up to 51% at 100 $\mug/ml$ in B16 melanoma cells. The tyrosinase activity and tyrosinase expression in B16 melanoma cells were reduced in a dose-dependent manner by SSE. Also, SSE was able to significantly inhibit tyrosinase and TRP-1 expression in mRNA level. These results suggest that SSE inhibited melanin production which may be dependent on tyrosinase activity and expression in B16 melanoma cells, and an effective whitening agent for the skin.

• 한국지하수토양환경학회지:지하수토양환경
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• 제23권6호
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• pp.104-113
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• 2018

A three-dimensional electrochemical process using nanosized zero-valent iron (NZVI)/activated carbon (AC) particle electrode and persulfate (PS) was developed for oxidizing pollutants. X-ray diffraction (XRD), scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS), and Brunauer-Emmett-Teller (BET) surface area analysis were performed to characterize particle electrode. XRD and SEM-EDS analysis confirmed that NZVI was impregnated on the surface of AC. Compared with the conventional two-dimensional electrochemical process, the three-dimensional particle electrode process achieved three times higher efficiency in phenol removal. The system with current density of $5mA/cm^2$ exhibited the highest phenol removal efficiency among the systems employing 1, 5, and $10mA/cm^2$. The removal efficiency of phenol increased as the Fe contents in the particle electrode increased. The particle electrode achieved more than 70% of phenol removal until it was reused for three times. The sulfate radical played a predominant role in phenol removal according to the radical scavenging test.