• 한국환경성돌연변이발암원학회지
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• 제24권3호
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• pp.121-127
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• 2004

Cytochrome P4501B1(CYP1B1) is known to be inducible by xenobiotic compounds such as policyclic aromatic hydrocarbon(PAH) and dioxins such as 2,3,7,8-tetrachloro-dibenzo-p-dioxin(TCDD). And these induction of CYP1B1 is also regulated by many categories of chemicals. In order to investigate the effects of several chemicals on CYP1B1 gene expression in Hepa-I and MCF-7 cells, 5' flanking DNA of human CYP1B1 was cloned into pGL3 basic vector containing luciferase gene, and then transfected into these cells. After treatment of chemicals, the luciferase activity was measured. CYP1B1 enzyme metabolize PAHs and estradiol. CYP1B1 metabolize estradiol to 4-hydrozyestradiol that is considered as carcinogenic metabolite. Luciferase activity was induced about 20 folds over that control by 1 nM TCDD (2,3,7,8-tetrachloto-p-dioxin). Recent industrialized society, human has been widely been exposed to widespread environmental contaminants such as PAHs(polycyclic aromatic hydrocarbon) that are originated from the imcomplete combustion of hydrocarbons. PAHs are known to be ligands of the AhR(aryl hydrocarbon receptor). Induction of cytochrome P4501B1(CYP1B1) in cell culture is widely used as a biomarker for PAHs. Therefore we have studied the effect of PAHs in the human breast cancer cells MCF-7 to evaluate bioactivity of PAHs. We have used the United State of America EPA selected 13 different PAHs, PAHs mixtures and extracts from environmental samples to evaluate the bioassay system. We examined effects of PAHs on the CYP1B1-luciferase reporter gene and CYP1B1 mRNA level. Benzo(k)fluoranthene and dibenzo(a, h)anthracene showed strong response to CYP1B1 promoter activity stimulation, and also CYP1B1 mRNAs increase in MCF-7 cells in a concentration-dependent manner. Acenaphthene, anthracene, benzo(b)fluoranthene, fluorene, fluoranthene, anphthanlene, pyrene, phenanthrene and carbazole were weak responders in MCF-7 cells. RT-PCR analysis indicated that PAHs significantly up-regulate the level of CYP1B1 mRNA.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2011년도 춘계학술대회 초록집
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• pp.117.2-117.2
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• 2011

Since Gratzel and co-workers developed a new type of solar cell based on the nanocrystalline TiO2 electrode, dye-sensitized solar cells (DSSCs) have attracted considerable attention on account of their high solar energy-to-conversion efficiencies (11%), their easy manufacturing process with low cost production compared to conventional p-n junction solar cells. The mechanism of DSSC is based on the injection of electrons from the photoexcited dye into the conduction band of nanocrystalline TiO2. The oxidized dye is reduced by the hole injection process from either the hole counter or electrolyte. Thus, the electronic structures, such as HOMO, LUMO, and HOMO-LUMO gap, of dye molecule in DSSC are deeply related to the electron transfer by photoexcitation and redox potential. To date, high performance and good stability of DSSC based on Ru-dyes as a photosensitizer had been widely addressed in the literatures. DSSC with Ru-bipyridyl complexes (N3 and N719), and the black ruthenium dye have achieved power conversion efficiencies up to 11.2% and 10.4%, respectively. However, the Ru-dyes are facing the problem of manufacturing costs and environmental issues. In order to obtain even cheaper photosensitizers for DSSC, metal-free organic photosensitizers are strongly desired. Metal-free organic dyes offer superior molar extinction coefficients, low cost, and a diversity of molecular structures, compared to conventional Ru-dyes. Recently, novel photosensitizers such as coumarin, merocyanine, cyanine, indoline, hemicyanine, triphenylamine, dialkylaniline, bis(dimethylfluorenyl)-aminophenyl, phenothiazine, tetrahydroquinoline, and carbazole based dyes have achieved solar-to-electrical power conversion efficiencies up to 5-9%. On the other hand, organic dye molecules have large ${\pi}$-conjugated planner structures which would bring out strong molecular stacking in their solid-state and poor solubility in their media. It was well known that the molecular stacking of organic dyes could reduce the electron transfer pathway in opto-electronic devices, significantly. In this paper, we have studied on synthesis and characterization of dendritic organic dyes with different number of electron acceptor/anchoring moieties in the end of dendrimer. The photovoltaic performances and the incident photon-to-current (IPCE) of these dyes were measured to evaluate the effects of the dendritic strucuture on the open-circuit voltage and the short-circuit current.

• 한국식품영양과학회지
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• 제46권3호
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• pp.335-342
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• 2017

고추냉이를 잎, 엽병 및 혼합한 전체 등으로 나누어 잎 열풍건조(LD), 엽병 열풍건조(PD), 전체 열풍건조(WD), 잎 증숙 열풍건조(LSD), 엽병 증숙 열풍건조(PSD), 전체 증숙 열풍건조(WSD) 등으로 구분하여 상온($20^{\circ}C$) 추출액, 열수($95^{\circ}C$) 추출액 등 6종 시료에 대하여 이화학적 특성을 조사하였다. 탁도와 갈변도는 각각 상온 추출과 증숙하지 않은 잎에서 더욱 높았다. pH는 열수 추출액이 상온 추출액보다 대체로 낮은 값을 나타냈다. Hunter 색도값인 L, a, b 값은 다소 차이는 있었으나 황색도인 b값은 잎이 줄기보다 유의적으로 아주 높게 나타났다. 카바졸 펙틴은 잎에서, 수용성 펙틴은 엽병에서 각각 함량이 높게 나타났다. 총폴리페놀 함량은 잎의 경우 LD20, LD95 각각 1,561.43 mg GAE/100 g, 1,163.02 mg GAE/100 g을 보여 열수 추출로 많이 감소하는 것으로 나타났다. 그러나 총플라보노이드는 엽병의 경우 추출온도별 유의적인 함량 차가 없는 것으로 나타났다. 관능검사 결과 추출액 LD95 값이 색, 향, 맛, 입안 촉감, 종합적 기호도 등 각 항목에서 가장 높게 나타났다. 전자혀에 의한 신맛, 짠맛, 감칠맛, 단맛 및 쓴맛을 분석한 결과 신맛은 LD20, PSD95, 짠맛은 WSD20, WSD95, 감칠맛은 PD20, PD95에서 각각 가장 높은 값을 나타내었다. 본 연구 결과 고추냉이 잎과 엽병을 이용한 추출액은 부위별 단독보다 병용하여 사용 시 품질 특성을 높일 수 있을 것으로 판단된다.