• Title/Summary/Keyword: hydroxy radical

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Synthesis and Characterization of Metal Complex Oxo Vanadium(Ⅳ) Complexes with Derivatives of Salicylaldoximes (옥심계 금속착물의 합성과 그 물성에 관한 연구 치환 살리실알데히드옥심의 바나듐(Ⅳ) 착물(1))

  • Lee, Kwang;Lee, Won Sik
    • Journal of the Korean Chemical Society
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    • v.39 no.8
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    • pp.611-616
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    • 1995
  • Oxovanadium(IV) complexes with salicylaldoxime, o-vanilline oxime, 2-hydroxy-4-methoxybenzaldoxime, 2-hydroxy-5-methoxybenzaldoxime and 2-hydroxy-5-nitrobenzaldoxime were synthesized. The complexes have been characterized by elemental analysis, electric conductivity measurement, infrared spectrometry, electronic spectrometry, mass spectrometry, and thermal analysis. The results of elemental analysis were well coincided with the theoretical values. The values of molar conductance of the complexes in DMF implicated that the complexes were non-electrolyte. The characteristic stretching frequency of V=O appeared strong band in the range of $980{\pm}20\;cm^{-1}.$ All the complexes showed two d-d transition in visible spectra and two charge transfer transitions in ultraviolet spectra. Results of mass spectrometry of $VO(sal)_2\;and\;VO(van)_2$ indicated two peaks corresponding to vanadium containing ion(I) of 1 : 2(metal to ligand) chelate and a fragment ion(II) of 1 : 1 chelate due to loss of ligand radical from ion(I). The thermal analysis showed the endothermic peak due to the thermal decomposition.

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Studies on the Development of Antihyperlipidemic Drugs from Oriental Herbal Medicines(I) -Antihyperlipidemic Activities of Oriental Herbal Medicines- (한방약물로부터 항고지혈증 치료약물개발(I) -수종 한약재의 항고지혈증 활성검색-)

  • Jung, Eun-Ah;Kim, Dong-Hyun;Lee, Sang-In;Kim, Nam-Jae
    • Korean Journal of Pharmacognosy
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    • v.30 no.4
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    • pp.368-376
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    • 1999
  • Twenty-four Oriental herbal medicines including Platycodi Radix and Scutellariae Radix, etc., which have been used for the cure of hyperlipidemia, coronary heart, disease were evaluated for the 3-hydroxy-3-methylglutaryl coenzyme A(HMG-CoA) reductase inhibition and antioxidant effect on a free radical, 1,1-diphenyl-2-picrylhydrazyl(DPPH) in vitro, and antihyperlipidemic effect on hyperlipidemic rats induced by Triton WR-1339 in vivo. 80% MeOH extract of eight herbs including Scutellariae Radix, Coptidis Rhizoma, Paeoniae Radix Rubra, Moutan Cortex Radicis, Angelicae Gigantis Radix, Bambusae Caulis in Taeniam, Cinnamomi Ramulus and Crataegi Fructus inhibited the HMG-CoA reductase activities and exhibited a radical-trapping action on a stable free radical, DPPH. On Triton WR-1339-induced hyperlipidemic rats, four herbs including Scutellariae Radix, Angelicae Gigantis Radix, Bambusae Caulis in Taeniam and Cinnamomi Ramulus showed respectively the significant suppression of serum total cholesterol, triglyceride, phospholipid and LDL-cholesterol levels and serum transaminase(ALT and AST) activities. From these results, it is suggested that each 80% MeOH extract of Scutellariae Radix, Angelicae Gigantis Radix, Bambusae Caulis in Taeniam and Cinnamomi Ramulus have effective antihyperlipidemic action against hyperlipidemia.

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Antioxidant and Whitening Effects of Agrimonia pilosa Ledeb Water Extract (짚신나물 물 추출물의 항산화 활성 및 미백효과에 관한 연구)

  • Kim, Tae-Hyuk;Kim, Jeong-Mi;Baek, Jong-Mi;Kim, Tae-Woo;Kim, Dae-Jung;Park, Jeong-Hae;Choe, Myeon
    • Korean Journal of Medicinal Crop Science
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    • v.19 no.3
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    • pp.177-184
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    • 2011
  • This study was performed to assess the antioxidant activities and whitening effects of Agrimonia pilosa Ledeb on melanin synthesis. The whitening effects of Agrimonia pilosa Ledeb water extracts were examined by in vitro mushroom tyrosinase assay and B16BL6 melanoma cells. We assessed inhibitory effect of Agrimonia pilosa Ledeb water extract on expression of melanogenic enzyme proteins including tyrosinase, tyrosinase-related protein 1 (TRP-1) and tyrosinase-related protein 2 (TRP-2) in B16BL6 cells. Inhibitory effect of Agrimonia pilosa Ledeb onto free radical generation was determined by measuring DPPH and hydroxyl radical scavenging activitie. Our results indicated that Agrimonia pilosa Ledeb water extract effectively inhibited free radical generation. In DPPH and hydroxy radical scavenging activity, Agrimonia pilosa Ledeb water extract had a potent anti-oxidant activity in a dose-dependent manner. They significantly inhibited tyrosinase activity in vitro and in B16BL6 melanoma cells. Also, Agrimonia pilosa Ledeb suppressed the expression of tyrosinase in B16BL6 melanoma cells. These results show that Agrimonia pilosa Ledeb inhibited melanin production on the melanogenesis. The underlying mechanism of Agrimonia pilosa Ledeb on whitening activity may be due to the inhibition of tyrosinase activity. We suggest that Agrimonia pilosa Ledeb may be useful as new natural active ingredients for antioxidant and whitening cosmetics.

Comparison or Antioxidative Activities or Crotaiarta sessiflora L. Extracts from Leaves, Seed, Stem and Root (활나물 부위별 추출물의 항산화 활성 비교)

  • Woo, NaRiYah;Kim, Tae-Su;Park, Hee-Woon;Park, Chun-Geon;Seong, Ha-Jeong;Ko, Sang-Heom;Jung, Jin-Woo;Kang, Myung-Hwa
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.34 no.9
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    • pp.1297-1301
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    • 2005
  • This study was carried to develop the new functional food material by exploring natural antioxidant substances of Crotalaria sessiflora L. We compared antioxidative activity of potential antioxidant substances extracted from Crotalaria sessiflora L. The order of extract yield of Crotalaria sessiflora L. were stem > loaves > seed > root. Antioxidative activities of Crotalaria sessiflora L. were measured by total polyphenol contents EDA (electron donating activity), SOD (superoxide dismutase) -like activity, hydroxyl radical scavenging ability and hydrogen peroxide radical scavenging ability. Total polyphenol acid content was much higher in leaves Ex than other extracts. And leaves Ex showed the most excellent antioxidative activity ($86.27\%$) in terms of SOD-like activity. The EDA was ordered loaves Ex > stem Ex > seed Ex > root Ex. Hydroxy radical scavenging ability was the most effective in loaves Ex, and hydorogen Peroxide radical scavenging ability was the highest in seed Ex. Therefore we could be certain that leaves Ex was the most effective in antioxidative activity from Crotalaria sessiflora L.

Effects of Mole Crickets (Gryllotalpa orientalis) Extracts on Anti-oxidant and Anti-inflammatory Activities. (땅강아지(Gryllotalpa orientalis) 추출물의 항산화 및 항염증 활성)

  • Heo, Jin-Chul;Lee, Dong-Yeob;Son, Min-Sik;Yun, Chi-Young;Hwang, Jae-Sam;Kang, Seok-Woo;Kim, Tae-Ho;Lee, Sang-Han
    • Journal of Life Science
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    • v.18 no.4
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    • pp.509-514
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    • 2008
  • Tremendous natural product extracts were used as a herb medicine remedy or therapy for centuries. Because these extracts have various biological activities, we examined the effects of Gryllotalpa orientalis extract for anti-oxidant and anti-inflammation activity by 1,1-diphenyl-2-picrylhydrazyl (DPPH), ferric reducing ability of plasma (FRAP), hydroxy radical scarvenging and cyclooxygenase-2 promoter assays. Gryllotalpa orientalis extracts were prepared from solvents such as distilled water (DW), dimethyl sulfoxide (DMSO), ethanol and methanol. The results showed that Gryllotalpa orientalis extracts have potent DPPH (methanol extract), FRAP (DW extract) and hydroxy radical scavenging (DW and methanol extracts) activity than any other extracts used. A significant inhibition of cyclooxygenase-2 (Cox-2) promoter activity was detected in the presence of DMSO extract or ethanol extract. Collectively, the present results suggested that Gryllotalpa orientalis extract could be used for anti-oxidant and/or anti-inflammation agent for human or agricultural purposes.

Precise Control of Thermoresponsive Properties of Polymers with Hydroxy Groups in the Side Chains (곁가지에 다양한 길이의 알코올 그룹을 지닌 고분자들의 저임계 용액온도 민감성 제어)

  • Lee, Hyung-Il
    • Polymer(Korea)
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    • v.39 no.1
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    • pp.165-168
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    • 2015
  • Thermoresponsive polymers were successfully synthesized by a combination of atom transfer radical polymerization (ATRP) and Cu(I)-catalyzed 1,3-dipolar cycloaddition of azide and alkynes (click chemistry). Poly(2-hydroxyethyl methacrylate) (PHEMA) was synthesized by ATRP, followed by introduction of alkyne groups using pentynoic acid, leading to HEMA-alkyne. Homopolymers having secondary amine groups, tertiary amines with hydroxyethyl and hydroxypropyl groups were synthesized by adding 2-azido-N-ethyl-ethanamine, 2-[(2-azidoethyl)amino]ethanol, and 2-[(2-azidoethyl)amino]propanol, respectively, to the PHEMA-alkyne backbone using click chemistry. Molecular weight (MW), molecular weight distribution (MWD), and click reaction efficiency were determined by gel permeation chromatography (GPC) and $^1H$ NMR spectroscopy. The transmission spectra of the 1.0 wt% aqueous solutions of the resulting polymers at 650 nm were measured as a function of temperature. Results showed that the lower critical solution temperature (LCST) could be easily controlled by the length of the hydroxyalkyl groups.

Screening of Antioxidative Compounds toward Human Low Density Lipoprotein (LDL) from Useful Plants (유용식물로부터 Human Low Density Lipoprotein(LDL)에 대한 항산화제의 탐색)

  • 임복규;류병호
    • The Korean Journal of Food And Nutrition
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    • v.17 no.2
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    • pp.138-146
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    • 2004
  • This study was designed to investigate antioxidative activity of substances isolated from 25 kinds of useful plants resources toward free radical and human low density lipoprotein(LDL). Methanol extracts of Oenothers odorate had the highest antioxidative activity similar with ${\alpha}$-tocopherol. Methanol extracts of Oenothers odorate was extracted again by the ethylacetate. The ethylacetate soluble acidic fraction obtained from methanol extract of Oenothers odorate showed highest activity toward human LDL. Each fraction was purified through Sepadex LH-20 chromatography by elution of chloroform-methanol mixture (90:10 v/v). Fraction, F-2 obtained from Oenothers odorate showed at highest levels of electron donating activity. Fraction, F-2 was identified as 3,4-dihydroxybenzoic acid and 3-hydroxycinnamic acid.

Effects of Chilbokyeum(七福飮) on the Biochemical Changes in Brain Tissue of Senile Rats (칠복음(七福飮)이 노화(老化) 백서(白鼠) 뇌조직(腦組織)의 생화학적(生化學的) 변화(變化)에 미치는 영향(影響))

  • Son Jeong-Seok;Lyu Young-Su
    • Journal of Oriental Neuropsychiatry
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    • v.8 no.2
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    • pp.25-37
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    • 1997
  • The present experiment was designed to examine catecholamines, 5-hydroxytryptamine, amino acids. malondialdehyde(MDA) and free radical scavenging activity, by administering Chilbokyeum extracts of a variety of concentration to senile brain rats. The results were summarized as followings ; 1. Chilbokyeum significantly increased noradrenalin in the hippocampus and hypothalamus of the brain tissue of senile rats, ad even though Chilbokyeum increased noradrenalin also in other brain tissue, there was no significance. 2. Chilbokyeum had no effects on dopamine changes in all brain tissue of senile rats.3. Chilbokyeum significantly increased 5-hydroxy-tryptamine in cerebellum, but decreased in other brain tissue.4. Chilbokyeum increased amino in the brain tissue of senile rats. 5. Chilbokyeum significantly decreased MDA and free radical in the brain tissue of senile rats. According to the above results, Chilbokyeum is assumed to improve brain function by reaction by reacting on biochemical of the senile brain, and that Chilbokyeum can be used to treat regressive brain disease carrying symptoms of psychoactive disorders.

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Preparation of Anhydrous Crosslinked Graft Copolymer Electrolyte Membrane (무가습 가교 가지형 공중합체 전해질 막의 제조)

  • Roh, Dong-Kyu;Koh, Joo-hwan;Park, Jung-tae;Seo, Jin-ah;Kim, Jong-hak
    • 한국신재생에너지학회:학술대회논문집
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    • 2009.06a
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    • pp.270-273
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    • 2009
  • A comb-like copolymer consisting of a poly(vinylidene fluoride-co-chlorotrifluoro-ethylene) backbone and poly(hydroxy ethyl acrylate) side chains, i.e. P(VDF-co-CTFE)-g-PHEA, was synthesized through atom transfer radical polymerization (ATRP) using CTFE units as a macroinitiator. Successful synthesis and a microphase-separated structure of the copolymer were confirmed by proton nuclear magnetic resonance (1H-NMR), FT-IR spectroscopy, and transmission electron microscopy (TEM). This comb-like polymer was crosslinked with 4,5-imidazole dicarboxylic acid (IDA) via the esterification of the -OH groups of PHEA and the -COOH groups of IDA. Upon doping with phosphoric acid ($H_3PO_4$) to form imidazole-$H_3PO_4$ complexes, the proton conductivity of the membranes continuously increased with increasing $H_3PO_4$ content. A maximum proton conductivity of 0.015 S/cm was achieved at $120^{\circ}C$ under anhydrous conditions. In addition, these P(VDF-co-CTFE)-g-PHEA/IDA/$H_3PO_4$ membranes exhibited good mechanical properties (765 MPa of Young's modulus), and high thermal stability up to $250^{\circ}C$, as determined by a universal testing machine (UTM) and thermal gravimetric analysis (TGA), respectively.

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Antioxidant, Anticancer and Immune Activation of Anthocyanin Fraction from Rubus coreanus Miquel fruits (Bokbunja) (복분자 안토시아닌 분획의 항산화, 항암 및 면역증진 효과)

  • Choung, Myoung-Gun;Lim, Jung-Dae
    • Korean Journal of Medicinal Crop Science
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    • v.20 no.4
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    • pp.259-269
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    • 2012
  • This study was performed to determined the antioxidant activities, anticancer and immuno-activities of anthocyanin fraction from Rubus coreanus Miquel fruits (Bokbunja). Anthocyanin fraction extracted from Bokbunja revealed the presence of three anthocyanin components, which were tentatively identified as cyanidin 3-O-sambubioside, cyanidin 3-O-xylosylrutinoside and cyanidin 3-O-rutinoside using RP-HPLC/DAD/MS. The anthocyanin fraction from Bokbunja always showed reducing power and high scavenging activities against DPPH, hydroxy radical (OH) and superoxide anion radical ($O_2{^-}$) similar to general synthetic antioxidant and polyphenol compounds from plant origin. Anthocyanin fraction from Bokbunja showed high inhibition on proliferation of LNCaP and A549 cells and did not inhibit the proliferation of other cancer cells. Immuno-activities of Anthocyanin fraction from Bokbunja were investigated, it showed high promotion of human B and T cells growth about 50% and secretion of IL-6 and TNF-${\alpha}$ by treatment after 6 days. Over all, the result of the study suggest that anthocyanin fraction from Bokbunja displays antioxidant activity comparable to that general synthetic antioxidant, also, anthocyanin fraction from Bokbunja are expected to be good candidate for development into source of anticaner and immuno-activator agent in food industry.