• 생명과학회지
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• 제21권10호
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• pp.1377-1384
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• 2011

Astaxanthin (ATX)은 다양한 생명체에서 생성되는 카로티노이드 색소이다. 본 연구에서는 ATX가 RAW264.7 cell에서 LPS에 의한 inducible nitric oxide synthase (iNOS), nitric oxide (NO), 염증성 사이토카인, nuclear factor-kappa B (NF-${\kappa}B$)와 reactive oxygen species (ROS)의 생성을 억제 시키는 지 또한, superoxide radical 소거능이 있는 지를 조사하였다. iNOS와 NF-${\kappa}B$는 immunoblot analysis로, interleukin (IL)-6와 tumour necrosis factor-${\alpha}$ (TNF-${\alpha}$)는 ELISA 법으로 분석하였다. NO 양은 nitrite의 양을 측정하였고, ROS는 2',7'-dichlorodihydrofluorescin diacetate (DCFH-DA) 법으로 superoxide radical 소거능은 superoxide radical scavenging activity assay로 검증하였다. 100 ${\mu}M$의 ATX 농도에서 LPS로 유도된 NO, IL-6 및 TNF-${\alpha}$ 같은 염증성 사이토카인의 생성 뿐만 아니라 iNOS 및 NF-${\kappa}B$의 발현도 억제되었다. 특히, IL-6 및 TNF-${\alpha}$ 생성에 있어 ATX의 최대 억제율은 각각 65.2% 및 21.2% 이었으며 LPS로 유도된 NF-${\kappa}B$의 전사활성을 억제하였다. 이러한 현상은 세포질에서 핵으로 NF-${\kappa}B$의 전위를 억제하는 것과 관련이 있다. 또한, 25-100 ${\mu}M$의 ATX 농도에서 세포 내 ROS 생성을 억제하였으며, 5 mg/ml 농도의 ATX는 동일농도의 ${\alpha}$-tocopherol에 비해 superoxide radical 소거능이 1.33배 높았다. 이러한 결과들은 ATX가 대식세포에서 ROS 생성 및 NF-${\kappa}B$ 활성을 저해하므로 iNOS의 발현, NO 및 염증성 사이토카인의 생성을 억제하며, 또한 우수한 superoxide radical 소거능을 보유한다는 것을 나타내었다. 결론적으로, ATX가 항염증제 및 항산화제로서 유용하게 사용될 수 있을 것으로 사료된다.

• 한국응용과학기술학회지
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• 제26권2호
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• pp.205-212
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• 2009

Solution copolymerization of Styrene(St.) with 2-Hydroxypropylacrylate(2-HPA) was carried out with Benzoylperoxide(BPO) as an initiator in toluene at $80^{\circ}C$ in a batch reactor. Reaction volume and reaction time were 0.3 liters, 8 hours respectively. The time to reach steady state was about the six time. The monomer reactivity ratios, $r_1$(St.) and $r_2$(2-HPA) were determined by both the Kelen-Tudos method and the Fineman-Ross method ; $r_1$(St.)=0.376(0.330), $r_2$(2-HPA)=0.408(0.778). The activation energy of thermal decomposition was in the range of $33{\sim}55kcal/mol$.

• KSBB Journal
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• 제29권3호
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• pp.199-204
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• 2014

To investigate the effect of Plantago asiatica L. Root extract on skin care, we measured anti-oxidant activity and whitening action. As a result of measuring DPPH radical scavenging activity to examine independent anti-oxidation of PRE, there was slight scavenging activity. Fluorescent materials DHE, DCF-DA and DHR were each used to measure superoxide anion, hydrogen peroxide, and hydroperoxide created in RAW 264.7 cells, all concentrations were found to dependently prevent ROS production. Tyrosinase activation was found to be blocked dose-dependant. Melanin production was also prevented dose-dependant, but the effects were slight. Therefore, it is expected to be used effectively in development of functional cosmetic materials.

• 대한화학회지
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• 제12권3호
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• pp.128-137
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• 1968

In the oligomerization of p-aminophenol by the catalytic action of Fe-EDTA complex in the aqueous medium, the mixed complex intermediate, Fe-EDTA-M type, is considered to be formed, from which active radicals of the monomer are produced. In this system, polymerization is presumed to proceed as follows: Free radical formation ${\to}$ Coupling ${\to}$ Activation ${\to}$ Coupling, and so on. In this study, the form of the monomer and coordination state in the mixed complex, the catalytic action of Fe-EDTA the complex, the reaction mechanism, and the structure of the oligomers are discussed.

• 생약학회지
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• 제47권3호
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• pp.287-294
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• 2016

Acetylcholinesterase (AChE) activation and amyloid-${\beta}$ ($A{\beta}$) aggregation are major biological markers of Alzheimer's disease. In the present study, we evaluated the inhibitory effects of 50 kinds of herbal formulas on AChE activity and $A{\beta}$ aggregation. Among them, Hwanglyeonhaedok-tang, Cheonwangbosim-dan, Makmundong-tang, and Gamisoyo-san had a potent effects on the inhbition of AChE activity. Sosiho-tang, Samsoeum, Cheonsimyeunjaeum, and Bunsimgieum exerted to have the inhibitory activity on $A{\beta}$ aggregation. In addition, these 8 herbal formulas showed the 3-ethyl-benzothiazoline-6-sulfonic acid (ABTS) radical scavenging activity, indicating their antioxidant activities.

• International Journal of Industrial Entomology and Biomaterials
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• 제28권2호
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• pp.85-91
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• 2014

This study was designed to find out the effect of Nosema spore on oxidative damages and antioxidant defence in the midgut of tasar silkworm Antheraea mylitta. Higher level of lipid peroxidation (LPX) and total hydroperoxides indicate the resultant oxidative stress in the Nosema exposed specimen. Increased superoxide dismutase (SOD) suggests activation of physiological mechanism to scavenge the superoxide radical produced during Nosema infection. Higher activities of catalase and glutathione-S-tranferase on $18^{th}$ d indicate adaptive behaviour of the tissue against oxyradicals. The results suggest that Nosema infection is involved in altering the active oxygen metabolism by modulating LPX and reactive oxygen species (ROS), which is indicative of pebrine disease disorder.

• 한국막학회:학술대회논문집
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• 한국막학회 1999년도 The 7th Summer Workshop of the Membrane Society of Korea
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• pp.55-58
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• 1999

Nafion supported catalytic membranes were found to be active, stable and selective in th partial oxidation of propane to oxygenates with H2O2 under mild condition. Addition of Fe2+ in liquid phase enhances the reaction rate. Reaction proceeds according to a radical mechanism based on th electrophilic activation of propane on superacid sites and subsequent reaction of the activated paraffin with OH radicals. The use of a catalytic membrane, which allow separation of the intermediate products from the liquid phase containing the oxidant, was found to be effective to perform selective partial oxidation of propane with high yields to oxygenated products.

• KSBB Journal
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• 제31권1호
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• pp.14-19
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• 2016

To investigate the effect of peanut sprout extract on skin care, we measured anti-oxidant activity and whitening action. As a result of measuring DPPH radical scavenging activity to examine independent anti-oxidation of peanut sprout extract, there was strongly scavenging activity. Fluorescent material DCF-DA was used to measure hydrogen peroxide created in RAW 264.7 cells, and all concentration dependently decreased ROS production. As a result of measuring nitric oxide to examine anti-inflammation of peanut sprout extract, there was strongly inhibited nitric oxide production in RAW 264.7 cells. Tyrosinase activation was found to inhibited dose-dependant. Melanin production was also prevented dose-dependant. Therefore, it is expected to be used effectively in development of functional cosmetic materials.

• Bulletin of the Korean Chemical Society
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• 제12권6호
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• pp.678-681
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• 1991

The Wittig-oxy-Cope rearrangements of deprotonated diallyl ether, I, $CH_2={\bar{C}}H-CH-O-CH_2-CH=CH_2$, have been investigated theoretically by the AM1 method. A two step mechanism forming a Wittig product ion, II, $(CH_2=CH)$ $(CH_2=CH-CH_2)$ $CHO^-$, through a radical-pair intermediate was found to provide the most favored reaction pathway in the Wittig rearrangement. The subsequent oxy-Cope rearrangement from species II also involves a two step mechanism through a biradicaloid intermediate. The intramolecular proton transfer in I (to form $CH_2=CH-CH_2-O-{\bar{C}}H-CH=CH_2$) is a higher activation energy barrier process compared to the Wittig and oxy-Cope rearrangements and is considered to be insignificant. These results are in good agreement with the condensed-phase as well as gas-phase experimental results.

• 한국식품위생안전성학회지
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• 제33권4호
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• pp.316-323
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• 2018

본 연구에서는 고지방 고콜레스테롤 식이 흰쥐에서 곰보배추 파우더가 간조직의 항산화 효소활성 및 산화적 손상에 미치는 영향을 관찰하였다. 실험군을 4군으로 나누어 정상 식이군, 고지방 고콜레스테롤 식이군, 고지방 고콜레스테롤 식이에 곰보배추 파우더를 5% 및 10% 첨가한 군으로 각각 나누었다. 간 조직 중의 항산화 효소계인 GSH-px, catalase 및 SOD 활성은 정상군에 비해 HF군에서는 감소되는 경향을 나타내었으나 HF군에 비해 곰보배추 파우더 공급군에서 유의적으로 증가되었다. Superoxide radical 함량을 mitochondria 및 microsome에서 측정한 결과 정상군에 비해 HF군에서 유의적인 증가를 나타내었으나 곰보배추 공급으로 유의하게 감소되었다. 특히 microsome 에서는 군간의 유의한 차이도 나타내었다. 간조직의 cytosol 및 mitochondria에서 $H_2O_2$의 함량에서는 곰보배추 공급군 모두에서 유의적인 감소로 정상군 수준을 나타내었다. 혈청에서 간수치 GOT 및 GPT를 측정한 결과 10%의 곰보배추의 공급으로 HF군에 비해 유의적으로 감소되었다. 간 조직의 microsome 및 mitochondria에서의 산화단백질 함량 또한 곰보배추 파우더의 공급으로 유의적으로 감소하였다. 과산화지질의 함량을 간조직에서 관찰 한 결과 고지방 고콜레스테롤 식이로 인해 증가된 과산화지질이 곰보배추 파우더를 공급한 군에서 유의한 감소를 나타내었다. 곰보배추의 공급으로 고지방 고콜레스테롤 식이로 손상된 간조직의 항산화계는 곰보배추 내 함유되어진 여러 생리활성 물질들이 항산화효소의 활성을 증가시켜 체내에서 생성된 free radical에 의한 산화를 억제시켰으리라 사료되어진다. 이로 미루어 곰보배추는 체내 조직의 산화를 억제하는 항산화작용에 효과적으로 기여함을 알 수 있었다.