• 생명과학회지
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• 제21권9호
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• pp.1214-1218
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• 2011

식물자원으로부터 항산화 물질을 확보 하기위해 한국 등에서 전통적으로 phytotherapy로 이용되어 온 Rubus crataegifolius Bge. 열매를 조사하였다. R. crataegifolius의 열매를 메탄올로 추출하였고 순차적으로 n-hexane, diethyl ether, and ethyl acetate로 분획화하였다. 각 분획물의 항산화 활성은 DPPH와 $H_2O_2$에 대항 인간 primary 세포인 keratinocyte (HK)를 이용하여 세포 독성 및 효능을 검증하였다. R. crataegifolius 열매 추출물은 비타민 C와 비슷한 강력한 DPPH (75.04%, 50%)와 $H_2O_2$ (79.9%, 54.1%) 소거능을 보였다. 분획물의 DPPP에 대한 소거능을 측정하였는데 n-hexane fraction (HF)은 20.3%, diethyl ether fraction (DF)은 68.8%, ethyl acetate fraction (EF)는 67.1% 그리고 residue fraction (RE)은 67.1%의 소거능을 보였으며 $H_2O_2$에 대해서는 2.2%, 1.6%, 10%, 그리고 50%로 각각 나타내었다. H2O2에 대한 HK의 세포 보호능을 확인하기 위해 산화적 스트레스 모델을 확립하였고(1 mM) 0.005-0.02%의 RE 분획물에서 $H_2O_2$에 대한 보호능을 발휘하였다. 따라서, R. crataegifolius의 열매 추출물은 $H_2O_2$유발 상처에 대하여 HK세포의 보호능을 가지며 강력한 항산화 활성을 가지고 있다.

• Asian Journal of Atmospheric Environment
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• 제5권4호
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• pp.247-262
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• 2011

This study assessed the health risks of childhood exposure to PBDEs via different possible pathways in children's facilities and indoor playgrounds. When PBDE contamination was measured, it was determined through multiple routes, including inhalation of indoor dust, dermal contact with product surfaces and children's hands, and incidental dust ingestion. Samples were collected from various children's facilities (playrooms, daycare centers, kindergartens, and indoor playgrounds) during summer (Jul-Sep, 2007) and winter (Jan-Feb, 2008). The hazard index (HI) was estimated for non-carcinogens, and PBDEs, such as TeBDE, PeBDE, HxBDE, and DeBDE, were examined. The sensitivity to the compounds did not exceed 1.0 (HI) for any of the subjects in any facility. However, current data about toxicity does not reflect effects that were fully sensitive in children, so there is uncertainty in the dose-response data. The contribution rates of PBDEs were 71.4 to 96.1% and 3.7 to 28.2% for intake and inhalation exposure, respectively, indicating that intake of floor dust and inhalation are the primary routes.

• 한국재료학회지
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• 제20권11호
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• pp.600-605
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• 2010

In order to meet the requirements of faster speed and higher packing density for devices in the field of semiconductor manufacturing, the development of Cu/Low k device material is explored for use in multi-layer interconnection. SiOC(-H) thin films containing alkylgroup are considered the most promising among all the other low k candidate materials for Cu interconnection, which materials are intended to replace conventional Al wiring. Their promising character is due to their thermal and mechanical properties, which are superior to those of organic materials such as porous $SiO_2$, SiOF, polyimides, and poly (arylene ether). SiOC(-H) thin films containing alkylgroup are generally prepared by PECVD method using trimethoxysilane as precursor. Nano voids in the film originating from the sterichindrance of alkylgroup lower the dielectric constant of the film. In this study, methyltriphenylsilane containing bulky substitute was prepared and characterized by using NMR, single-crystal X-ray, GC-MS, GPC, FT-IR and TGA analyses. Solid-state NMR is utilized to investigate the insoluble samples and the chemical shift of $^{29}Si$. X-ray single crystal results confirm that methyltriphenylsilane is composed of one Si molecule, three phenyl rings and one methyl molecule. When methyltriphenylsilane decomposes, it produces radicals such as phenyl, diphenyl, phenylsilane, diphenylsilane, triphenylsilane, etc. From the analytical data, methyltriphenylsilane was found to be very efficient as a CVD or PECVD precursor.

• Advances in Traditional Medicine
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• 제7권1호
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• pp.85-93
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• 2007

Free radicals are known to play important role in pathophysiology of hepatic disorders and antioxidants are employed along with other chemotherapeutic agents in treatment of such diseases. In search of natural antioxidant, successive extracts of Hypericum (H.) hookerianum (Family: Hypericaceae) were evaluated by in vitro and in vivo methods. Extracts of aerial parts of H. hookerianum were subjected for 1,1-diphenyl 2-picryl hydrazyl radical scavenging activity (DPPH assay), nitric oxide radicals scavenging assay and thiobarbituric acid reactive substances (TBARS) assay. Methanolic extract was found to be more active than other extracts in DPPH and in vitro TBARS assay with $IC_{50}$ at 5.82 ${\pm}$ 1.33 ${\mu}g/ml$ and 49.78 ${\pm}$ 3.79 ${\mu}g/ml$ respectively. While petroleum ether extract showed more potentials in scavenging the nitric oxide radicals with $IC_{50}$ 220.97 ${\pm}$ 2.69 ${\mu}g/ml$. The administration of $CCl_{4}$ to the control animals caused decrease in the level of catalase and superoxide dismutase, together with significant increase in the level of TBARS in liver and kidney. Reversal of these changes towards normal group was observed by administration of H. hookerianum methanolic extract at 50 and 100 mg/kg body weight, while other extracts were found to be less active.

• 폴리머
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• 제38권5호
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• pp.602-612
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• 2014

폴리(디메틸 실록산)(PDMS) 성분을 포함하는 폴리우레탄(PU-Si)을 합성하고 이들의 열적 특성과 형상기억 특성을 분석하였다. 이를 위하여 메틸렌디페닐 디이소시아네이트와 1,4-부탄디올을 하드세그먼트(HS) 성분으로 하고, 소프트세그먼트(SS) 성분으로 PDMS 디올과 폴리(테트라메틸렌 에테르 글리콜)(PTMEG) 혼합폴리올을 사용하여 HS 함량이 각각 23%와 32%이면서 PDMS 함량이 다른 PU-Si를 용액중합법으로 합성하였다. HS 함량이 23%인 PU-Si의 경우 PDMS 함량 증가에 따라 SS의 냉결정화온도($T_{cc}$)와 용융결정화온도는 증가하였으나 용융온도($T_m$)에는 변화가 없었다. HS 함량이 32%인 시료들의 경우 PTMEG의 $T_m$이 HS 함량 23%인 시료들보다 약간 높은 온도에서 나타났으며 $T_{cc}$는 관찰되지 않았다. PDMS 성분이 포함된 PU-Si 필름들은 PU에 비해 형태고정성은 약간 좋지 않지만 형상기억 효과는 더 우수하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1998년도 춘계학술대회 논문집
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• pp.399-402
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• 1998

Electroluminescent(EL) devices based on organic thin films have attracted lots of interests in large-area light-emitting display. One of the problems of such device is a lifetime, where a degradation of the cell is possibly due to an organic layers thickness, morphology and interface with electrode. In this study, light-omitting organic electroluminescent devices were fabricated using Alq$_3$(8-hydroxyquinolinate aluminum) and TPD(N,N'-diphenyl-N,N'-bis(3-methylphenyl(1-1\`-biphenyl]-4,4'-diamine). Where Alq$_3$ is an electron-transport and emissive layer, TPD is a hole-transport layer. The cell structure is ITO/TPD/Alq$_3$/Al and the cell is fabricated by vacuum evaporation method. In a measurement of current-voltage characteristics, we obtained a turn-on voltage at about 9 V. We also investigated stability of the devices using buffer layer with blend of PEI (Poly ether imide) and TPD by varying mot ratios between ITO and Alq$_3$. In current-voltage characteristics measurement, we obtained the turn-on voltage at about 6 V and observed an anomalous behavior at 3∼4 V. And we used other buffer layer of PEDT(3,4-pyrazino-3',4'-ethylenedithio-2,2',5,5'-tetrathiafulvalenium) with ITO/PEDT/TPD/Alq$_3$Al structure. We observed a surface morphology by AFM(Atomic Force Microscopy), UV/visible absorption spectrum, and PL(Photoluminescence) spectrum. We obtained the UV/visible absorption peak at 358nm in TPD and at 359nm in Alq$_3$, and the PL peaks at 410nm in TPD and at 510nm in Alq$_3$. We also studied EL spectrum in the cell structure of ITO/(TPD+PEI)/Alq$_3$/Al.

• 한국약용작물학회지
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• 제27권3호
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• pp.208-217
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• 2019

Background: In the present study, we identified two cytotoxic compounds from the root of Rumex crispus L. using a bioassay-based method. Methods and Results: Compared with the other fractions, the diethyl ether ($Et_2O$) fraction of R. crispus root extract exhibited the strongest of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging effect [scavenging concentration 50% $(SC_{50})=63.8{\pm}1.47{\mu}g/m{\ell}$], nitric oxide (NO) production inhibitory effect on the mouse macrophage cell line RAW264.7 [inhibitory concentration 50% $(IC_{50})=60.9{\pm}7.52{\mu}g/m{\ell}$] and cytotoxicity effect on the human hepatoma cell line, HepG2 [lethal concentration 50% $(LC_{50})=115.4{\pm}1.86{\mu}g/m{\ell}$]. According to the bioassay-based method, two cytotoxic compounds were purified from the $Et_2O$ fraction by using column chromatography and preparative high performance liquid chromatography (prep-HPLC). These two compounds were identified as parietin and chrysophanol by using nuclear magnetic resonance (NMR) and liquid chromatography quadruple time of flight mass spectrometry (LC-QTOF-MS). In addition, both parietin and chrysophanol exhibited a cytotoxicity effect on HepG2 cells, their $LC_{50}$ values were $169.1{\pm}17.67{\mu}M$ and $111.5{\pm}6.62{\mu}M$, respectively. Conclusions: Parietin and chrysophanol isolated from the $Et_2O$ fraction of the R. crispus root extract showed cytotoxicity in HepG2 cell.

• 대한본초학회지
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• 제30권2호
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• pp.31-36
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• 2015

Objectives : In this study, we demonstrated the antioxidant activities and the inhibitory effect on oxidative DNA damage of ethyl acetate fractions extracted from Sophorae Flos and Sophorae fructus. Methods : Sophorae Flos and Sophorae fructus were extracted with methanol(MeOH) and divided to Petroleum ether, Ethyl acetate(EtOAC) and Water fraction. The antioxidant activities were conducted by the 1,1-diphenyl-2-picryl hydrazyl(DPPH) radical, 2, 2'-Azine-bis(3-ethylbenzothiazoline-6 sulfonic acid) diammonium salt(ABTS) radical scavenging assay, $Fe^{2+}$ chelating assay and Reducing power assay. The inhibitory effect of DNA damage were characterized on ${\varphi}$ X-174 RF I plasmid DNA cleavage assay. In addition, we analyzed the Total phenol contents and the Vitamin C contents of Sophorae Flos and Sophorae fructus. Results : The results of DPPH were 92.71% and 94.72%, ABTS were 87.16% and 62.44%, and $Fe^{2+}$ chelating were 95.81% and 85.11% at $200{\mu}g/m{\ell}$ of Sophorae Flos and Sophorae fructus respectively. The Sophorae Flos showed stronger effect than Sophorae fructus in Reducing Power assay. Total phenol content was 111.77 mg/g and 122.54 mg/g, and Vitamin C content was 2.59 mg/g and 3.03 mg/g. Also both Sophorae Flos and Sophorae fructus have inhibitory antioxidant effect on ${\varphi}$ X-174 RF I plasmid DNA cleavage assay. Conclusions : Over all, this study suggests that Sophorae Flos and Sophorae fructus can be used as not only effective antioxidant but also natural medicine.

• Journal of Applied Biological Chemistry
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• 제60권4호
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• pp.383-390
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• 2017

쉽게 산화되는 지방이 커피의 풍미에 중요한 영향을 미치는 주요 요소 중 하나라는 것과 chlorogenic acid (CGA)가 커피의 주요 항산화 물질이라는 점을 고려하여 본 연구에서는 커피생두의 열처리 가공 정도와 단기저장 기간에 따라 변화하는 지방의 산화와 CGA의 농도변화와 동시에 항산화활성을 분석하였다. 커피 원두를 얻기 위한 열처리 가공 시간이 길수록 diethyl ether로 추출되는 지방의 양이 증가하였으며 지방의 산가는 분쇄된 medium과 dark 커피에서 가공 첫날 $8.91{\pm}0.16$과 $10.37{\pm}0.27$를 각각 보이다가 60일 간의 저장기간 후에는 $17.81{\pm}0.11$과 $17.93{\pm}0.09$로 증가하였으나 분쇄 생두에서는 $4.47{\pm}0.11$로부터 $11.89{\pm}0.18$로 증가함을 보였다. CGA 함량은 10 g 커피를 이용하여 커피를 제조할 경우 생두, medium, dark 커피의 경우 각각 $310{\pm}8.2$, $282{\pm}11.2$, $5.9{\pm}0.23mg$을 나타내었으며 이들 농도는 60일간의 저장 기간 동안 변화되지 않고 유지되었을 뿐 아니라 CGA를 분리하는 액체 크로마토그래피 조건에서 얻어지는 용리 크로마토그램도 저장기간 동안 변화되지 않고 유지되어 CGA가 저장기간 동안 다른 물질로 변화되지 않음을 보였다. 2,2-diphenyl-1-picrylhydrazyl와 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid radical 소거능 분석에서 원두 간 그리고 저장기간에 따른 특이적인 변화를 보이지 않았으며 ARE-luciferase 활성 분석에서는 오히려 roasting이 진행될수록 저장기간이 오랠수록 항산화활성이 증가함을 보였고 총 polyphenol의 함량은 roasting가공이 진행됨에 따라 감소함을 보였기 때문에 커피의 항산화활성은 polyphenol 외에 다른 물질, 즉, melanoidin과 같은 물질이 생성되어 항산화활성을 높이고 커피 풍미에도 영향을 미칠 가능성을 보였다.

• Asian-Australasian Journal of Animal Sciences
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• 제30권11호
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• pp.1620-1632
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• 2017

Objective: This study evaluated the effects of a traditional Chinese medicine formula (TCMF) on muscle fiber characteristics in finishing pigs and the effects of the formula's extract (distilled water, ethyl acetate and petroleum ether extraction) on porcine cell proliferation and isoforms of myosin heavy chain (MyHC) gene expression in myocytes. Methods: In a completely randomized design, ninety pigs were assigned to three diets with five replications per treatment and six pigs per pen. The diets included the basal diet (control group), TCMF1 (basal diet+2.5 g/kg TCMF) and TCMF2 (basal diet+5 g/kg TCMF). The psoas major muscle was obtained from pigs at the end of the experiment. Muscle fiber characteristics in the psoas major muscle were analyzed using myosin ATPase staining. Cell proliferation was measured using 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) dye and cytometry. Isoforms of MyHC gene expression were detected by real-time quantitative polymerase chain reaction. Results: The final body weight and carcass weight of finishing pigs were increased by TCMF1 (p<0.05), while the psoas major muscle cross-sectional area was increased by TCMF (p<0.05). The cross-sectional area and diameter of psoas major muscle fiber Ι, IIA, and IIB were increased by TCMF2 (p<0.05). The cross-sectional area and fiber diameter of psoas major muscle fiber IIA and IIB were increased by diet supplementation with TCMF1 (p<0.05). Psoas major muscle fiber IIA and IIB fiber density from the pigs fed the TCMF1 diet and the type IIB fiber density from the pigs fed the TCMF2 diet were lower compared to pigs fed the control diet (p<0.05). Pigs fed TCMF2 had a higher composition of type Ι fiber and a lower percentage of type IIB fiber in the psoas major muscle (p<0.05). The expression levels of MyHC Ι, MyHC IIa, and MyHC IIx mRNA increased and the amount of MyHC IIb mRNA decreased in the psoas major muscle from TCMF2, whereas MyHC Ι and MyHC IIx mRNA increased in the psoas major muscle from TCMF1 (p<0.05). Peroxisome proliferator-activated receptor ${\gamma}$ $coactivator-1{\alpha}$ and CaN mRNA expression in the psoas major muscle were up-regulated by TCMF (p<0.05). Porcine skeletal muscle satellite cell proliferation was promoted by $4{\mu}g/mL$ and $20{\mu}g/mL$ TCMF water extraction (p<0.05). Both $1{\mu}g/mL$ and $5{\mu}g/mL$ of TCMF water extraction increased MyHC IIa, MyHC IIb, and MyHC IIx mRNA expression in porcine myocytes (p<0.05), while MyHC Ι mRNA expression in porcine myocytes was decreased by $5{\mu}g/mL$ TCMF water extraction (p<0.05). Porcine myocyte MyHC Ι and MyHC IIx mRNA expression were increased, and MyHC IIa and MyHC IIb mRNA expression were down-regulated by $5{\mu}g/mL$ TCMF ethyl acetate extraction (p<0.05). MyHC Ι and MyHC IIa mRNA expression in porcine myocytes were increased, and the MyHC IIb mRNA expression was decreased by $1{\mu}g/mL$ TCMF ethyl acetate extraction (p<0.05). Four isoforms of MyHC mRNA expression in porcine myocytes were reduced by $5{\mu}g/mL$ TCMF petroleum ether extraction (p<0.05). MyHC IIa mRNA expression in porcine myocytes increased and MyHC IIb mRNA expression decreased by $1{\mu}g/mL$ in a TCMF petroleum ether extraction (p<0.05). Conclusion: These results indicated that TCMF amplified the psoas major muscle cross-sectional area through changing muscle fiber characteristics in finishing pigs. This effect was confirmed as TCMF extraction promoted porcine cell proliferation and affected isoforms of MyHC gene expression in myocytes.