• Title/Summary/Keyword: O-D analysis

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Constituents of Flowers of Carthamus tinctorius L. and Their Antioxidant Activity (홍화의 성분 분리 및 항산화 활성)

  • Choi, Hyun-Gyu;Jiang, Yan-Fu;Park, Sung-Hee;Son, Ae-Ryang;Na, Min-Kyun;Lee, Seung-Ho
    • Korean Journal of Pharmacognosy
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    • v.42 no.2
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    • pp.110-116
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    • 2011
  • As part of our ongoing study focused on the discovery of antioxidants from natural products by measuring the DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging activity, methanol extract of flowers of Carthamus tinctorius L. was found to show potent antioxidant activity. Activity-guided fractionation of the methanol extract lead to the isolation of twenty compounds including two flavonol glycosides, quercertin-3-O-${\beta}$-D-glucopyranoside (12) and kaempferol-3-O-${\alpha}$-L-rhamnopyranosyl-${\beta}$-D-glucopyranoside (18), two flavanone glycosides, (2S)-4',5,6,7-tetrahydroxyflavanone 6-O-${\beta}$-D-glucopyranoside (15) and (2R)-5,7,8',4-tetrahydroxyflavanone 8-O-${\beta}$-D-glucopyranoside (16), and two acetylenic glycosides, 8Z-decaene-4,6-diyne-1-O-${\beta}$-D-glucopyranoside (13) and 4,6-decadiyne-1-O-${\beta}$-D-glucopyranoside (14). Their chemical structures were identified by using spectroscopic analysis. Among them, compounds 12-18 were tested in DPPH assay. Compounds 13-16 were first reported to their antioxidant activity. Quercertin-3-O-${\beta}$-D-glucopyranoside (12) showed the most potent inhibitory effect on DPPH with $IC_{50}$ value of 56.7 ${\mu}M$.

TiO2 Photocatalytic Reaction on Glass Fiber for Total Organic Carbon Analysis (총유기탄소 분석을 위한 유리섬유를 이용한 이산화티타늄 광촉매 반응)

  • Park, Buem Keun;Lee, Young-Jin;Shin, Jeong Hee;Paik, Jong-Hoo
    • Journal of Sensor Science and Technology
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    • v.31 no.2
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    • pp.102-106
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    • 2022
  • Currently, the demand for real-time monitoring of water quality has increased dramatically. Total organic carbon (TOC) analysis is a suitable method for real-time analysis compared with conventional biochemical oxygen demand (BOD) and chemical oxygen demand (COD) methods in terms of analysis time. However, this method is expensive because of the complicated internal processes involved. The photocatalytic titanium dioxide (TiO2)-based TOC method is simpler as it omits more than three preprocessing steps. This is because it reacts only with organic carbon (OC) without extra processes. We optimized the rate between the TiO2 photocatalyst and binder solution and the TiO2 concentration. The efficiency was investigated under 365 nm UV exposure onto a TiO2 coated substrate. The optimized conditions were sufficient to apply a real-time monitoring system for water quality with a short reaction time (within 10 min). We expect that it can be applied in a wide range of water quality monitoring industries.

Anti-oxidative Phenolic Compounds from Sophorae Fructus

  • Kim, Hyun-Jung;Kim, Min-Kee;Shim, Jae-Gul;Yeom, Seung-Hwan;Kwon, Suk-Hyung;Lee, Min-Won
    • Natural Product Sciences
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    • v.10 no.6
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    • pp.330-334
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    • 2004
  • Four isoflavonoids and three flavonoids, and a gallotannin were isolated from the fruits of Sophora japonica (Leguminosae). Their structures were identified as genistein (1), sophoricoside (2), genistein-4'-O--L-rhamnopyranoside (3), $genistein-4'-O-{\alpha}-L-rhamnopyranosly-(1{\rightarrow}2)-{\beta}-D-glucopyranoside$ (4), $kaempferol-3-O-{\alpha}-D-sophoroside$ (5), $kaempferol-3-O-{\beta}-D-glucopyranosyl-(1{\rightarrow}2)-{\alpha}-L-rhamnopyranosly-(1{\rightarrow}6)-{\beta}-D-glucopyranoside$ (6), rutin (7) and gallic acid $4-O-{\beta}-D-(6'-O-galloyl)-glucopyranoside$ (8) by chemical and spectroscopic analysis and comparisons with previously reported spectral data. Compounds 3 and 8 were isolated for the first time from this plant. Anti-oxidative activity was evaluated for the isolated compounds. 8 exhibited potent anti-oxidative activity against the radical scavenging ability of DPPH with the $IC_{50}$ value of $17.1\;{\mu}g/ml$.

A Comparison Study on Software Testing Efforts (소프트웨어 테스트 노력의 비교 연구)

  • Choe, Gyu-Sik
    • Proceedings of the KIEE Conference
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    • 2003.11c
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    • pp.818-822
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    • 2003
  • We propose a software-reliability growth model incoporating the amount of uniform and Weibull testing efforts during the software testing phase in this paper. The time-dependent behavior of testing effort is described by uniform and Weibull curves. Assuming that the error detection rate to the amount of testing effort spent during the testing phase is proportional to the current error content, the model is formulated by a nonhomogeneous Poisson process. Using this model the method of data analysis for software reliability measurement is developed. The optimum release time is determined by considering how the initial reliability R(x|0) would be. The conditions are $R(x|0)>R_o$, $R_o>R(x|0)>R_o^d$ and $R(x|0)<R_o^d$ for uniform testing efforts. Ideal case is $R_o>R(x|0)>R_o^d$. Likewise, it is $R(x|0){\geq}R_o$, $R_o>R(x|0)>R_o^{\frac{1}{g}$ and $R(x\mid0)<R_o^{\frac{1}{g}}$ for Weibull testing efforts. Ideal case is $R_o>R(x|0)>R_o^{\frac{1}{g}}$.

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Influence of Thermal Annealing on the Microstructural Properties of Indium Tin Oxide Nanoparticles

  • Kim, Sung-Nam;Kim, Seung-Bin;Choi, Hyun-Chul
    • Bulletin of the Korean Chemical Society
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    • v.33 no.1
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    • pp.194-198
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    • 2012
  • In this work, we studied the microstructural changes of ITO during the annealing process. ITO nanoparticles were prepared by the sol-gel method using indium tin hydroxide as the precursor. The prepared sample was investigated using TEM, powder XRD, XPS, DRIFT, and 2D correlation analysis. The O 1s XPS spectra suggested that the microstructural changes during the annealing process are closely correlated with the oxygen sites of the ITO nanoparticles. The temperature-dependent in situ DRIFT spectra suggested that In-OH in the terminal sites is firstly decomposed and, then, Sn-O-Sn is produced in the ITO nanoparticles during the thermal annealing process. Based on the 2D correlation analysis, we deduced the following sequence of events: 1483 (due to In-OH bending mode) ${\rightarrow}$ 2268, 2164 (due to In-OH stretching mode) ${\rightarrow}$ 1546 (due to overtones of Sn-O-Sn modes) ${\rightarrow}$ 1412 (due to overtones of Sn-O-Sn modes) $cm^{-1}$.

Standardization and Seasonal Variation of Quercetin Glycoside in Eucommiae Folium (두충엽 함유 퀘르세틴배당체의 함량 표준화 및 계절적 변화)

  • Ham, In-Hye;Lee, Seung-Jae;Kim, Ho-Hyun;Kang, In-Ho;Jin, Hee-Ouk;Whang, Wan-Kyunn
    • Korean Journal of Pharmacognosy
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    • v.33 no.3 s.130
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    • pp.194-199
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    • 2002
  • The radix and folium of Eucommia ulmoides(Eucommiaceae) has been used for backache, atrophy of the leg and knee, enuresis, hypertension. In order to evaluate to quality of folium, we have been isolated a main compound as a standard compound, which was elucidated $quercetin-3-O-{\beta}-D-xylopyranosyl(l{\rightarrow}2)-{\beta}-D-glucopyranoside$ through it's physicochemical data and IR, FAB-Mass, $^{13}C-NMR$ and $^{1}H-NMR$ analysis. It was analyzed by HPLC system using 17% $CH_3CN$ as a solvent system. The amount of $quercetin-3-O-{\beta}-D-xylopyranosyl(l{\rightarrow}2)-{\beta}-D-glucopyranoside$ from Eucommiae folium was in the range of $0.056{\pm}0.022$ mg(n=7) and also from the results of analysis through seasonal variation$(June{\sim}October)$ September and October have been evaluated to be very high in it's content.

Flavonoids from the Roots of Rhodiola sachalinensis (홍경천의 플라보노이드 화합물)

  • Lee, Yeon-Ah;Cho, Soo-Min;Lee, Min-Won
    • Korean Journal of Pharmacognosy
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    • v.33 no.2 s.129
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    • pp.116-119
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    • 2002
  • Chemical investigation of the roots of Rhodiola sachalinensis A. Bor. (Crassulaceae) has led to the isolation of four flavonoids. Structures of these compounds were identified as $kaempferol-3-O-{\beta}-D-glucopyranoside$ (1), $kaempferol-3-O-{\beta}-D-sophoroside$ (2), $herbacetin-3-O-{\beta}-D-glucopyranoside$ (3) and $herbacetin-7-O-{\beta}-D-glucopyranosyl(1{\rightarrow}3)-{\alpha}-L-rhamnopyranoside$ (4) by the analysis of spectroscopic evidences and comparision with the data of authentic samples.

Phenolic Components from the Aerial Parts of Bromus japonicus Thunb. (참새귀리 지상부의 페놀성 성분)

  • Tao, Chao;Ahn, Dal-Rae;Xing, Ming Ming;Lee, Eun-Byeol;Kim, Dae-Keun
    • Korean Journal of Pharmacognosy
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    • v.43 no.3
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    • pp.213-216
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    • 2012
  • Six phenolic compounds were isolated from the aerial parts of Bromus japonicus (Gramineae) through repeated column chromatography. Their chemical structures were elucidated as luteolin (1), caffeic acid (2), luteolin-7-O-${\beta}$-D-glucopyranoside (3), quercetin-3-O-${\beta}$-D-galactopyranoside (4), quercetin-3-O-${\beta}$-D-glucopyranoside (5), and luteolin-4'-O-${\beta}$-D-glucopyranoside (6), respectively, by spectroscopic analysis. These compounds were isolated for the first time from this plant.

Antilipoperoxidant Activity of Antraquinone and Stilbene from Polygonum cuspidatum (호장으로부터 분리한 안트라퀴논 및 스틸벤 화합물의 지질과산화 저해활성)

  • Joo, Si-Mong;Lee, Min-Won;Yang, Ki-Sook
    • YAKHAK HOEJI
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    • v.51 no.2
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    • pp.140-144
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    • 2007
  • Polygonum cuspidatum has been used as treatments of dermatitis, gonorrhea, inflammation, and hyperlipidaemia in traditional medicine. We examined liver protective effect on CCl$_4$ inducing hepatotoxicity and anti-oxidative activity by TBA method. Phytochemical examination of Polygonum cuspidatum led to the isolation and characterization of emodin 8-O-${\beta}$-D-glucopyranoside (compound 1), and trans-resveratrol 3-O-${\beta}$-D-glucopyranoside (compound 2). Compounds 1 and 2 enhanced the inhibition of anti-lipid peroxidative effects in liver homogenate. In chemical parameters obtained from serum analysis, compounds 1 and 2 also revealed significant decrease in hepatotoxicity. These results suggested that the antraquinone and stilbene which were isolated from Polygonum cuspidatum might be used as therapeutic agent of hepatitis.

Chemical Constituents of the Rhizomes of Sparganium stoloniferum (흑삼릉 근경의 성분)

  • 신수용;도상학;신국현
    • YAKHAK HOEJI
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    • v.44 no.4
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    • pp.334-339
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    • 2000
  • The present study was carried out to evaluate biologically active components of the rhizomes of Sparganium stoloniferum and to supply the preliminary data for the chemotaxonomy and the medicinal application. Extraction and systematic fractionation of the rhizomes by column chromatography led to the isolation of six compounds from ethylacetate and n-butanol soluble fractions. Elucidation of the chemical structures of these compounds by physicochemical and apectral analysis demonstrated that compound I,II ,III,IV,V and Ⅵ were $\beta$-sitosterol, $\beta$-sitosterol-3-$\beta$-D-glucuronopyranoside, 3- (4-hydroxyphenyl)-2-propenoic acid, sorbose, 1-O-$\beta$-D-glucopyranosyl-(2S, 3R, 4E, 8Z)-2-[(2(R)-hydroxyeicosanoyl)amido]-4,8-octadecadiene-1,3-diol, and $\beta$-sitosterol-3-O-$\beta$-D-glucopyranoside, respectively.

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