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Maysa Furlan - One of the best experts on this subject based on the ideXlab platform.

  • evaluation of antioxidant capacity and synergistic associations of quinonemethide triterpenes and phenolic substances from Maytenus ilicifolia celastraceae
    Molecules, 2010
    Co-Authors: Vânia Aparecida De Freitas Formenton Macedo Dos Santos, Daniela P Santos, Ian Castrogamboa, Maria Valnice Boldrin Zanoni, Maysa Furlan
    Abstract:

    This work describes the isolation of the secondary metabolites identified as the quinonemethides maytenin (1) and pristimerin (2) from Maytenus ilicifolia extracts obtained from root barks of adult plants and roots of seedlings and their quantification by high performance liquid chromatography coupled to a diode array detector. The electrochemical profiles obtained from cyclic voltammetry and a coulometric detector coupled to high-performance liquid chromatography contributed to the evaluation of their antioxidant capacity. The antioxidant properties of individual components and the crude extracts of the root barks of Maytenus ilicifolia were compared and the possible synergistic associations of quinonemethide triterpenes and phenolic substances were investigated by using rutin as a model phenolic compound.

  • profile of Maytenus aquifolium action over free radicals and reactive oxygen species
    Revista Brasileira De Ciencias Farmaceuticas, 2007
    Co-Authors: Jose Carlos Rebuglio Vellosa, Vânia Aparecida De Freitas Formenton Macedo Dos Santos, Maysa Furlan, Vanessa De Frias Barbosa, Najeh Maissar Khalil, Iguatemy Lourenco Brunetti, Olga Maria Mascarenhas De Faria Oliveira
    Abstract:

    Especies Reativas do Oxigenio (ERO) e radicais livres tem tido implicacoes na iniciacao e evolucao de muitas doencas ou nas causas das mesmas em organismos vivos; ha portanto, necessidade continua por moleculas antioxidantes para inativar ERO/radicais livres. Estudos sobre extratos brutos de plantas tem demonstrado suas acoes antioxidante e sequestradora de radicais livres. Especies do genero Maytenus sao utilizadas, em varios paises, como medicamentos tradicionais no combate a ulceras gastricas, dispepsia e outras desordens gastricas, bem como por suas propriedades antiinflamatorias. Neste estudo, o extrato bruto etanolico da raiz da Maytenus aquifolium (Celastraceae) foi avaliado quanto a sua habilidade em sequestrar radicais livres e outras especies reativas do oxigenio. Os resultados sao expressos como porcentagem de inibicao das especies ativas. O extrato foi eficiente contra as especies estudadas: radical DPPH (inibicao alcancada = 35,5 ± 1,3 %), ABTS•+ (IC50 = 0,0036 ± 0,0003 mg/mL), HOCl (IC50 = 0,002 ± 0,0001 mg/mL ), O2•- (inibicao alcancada = 36,0 ± 2,1 %), and NO· (inibicao alcancada = 18,3 ± 0,4 %).

  • in vitro propagation of Maytenus ilicifolia celastraceae as potential source for antitumoral and antioxidant quinomethide triterpenes production a rapid quantitative method for their analysis by reverse phase high performance liquid chromatography
    Arkivoc, 2004
    Co-Authors: Waldemar Buffa Filho, Ana Maria Soares Pereira, Maysa Furlan, Vanderlan Da Silva Bolzani, Sarazete Izidia Vaz Pereira, Suzelei Castro Francab
    Abstract:

    Cell culture of Maytenus ilicifolia were established in order to produce and to quantify the antitumoral and antioxidant quinonemethide triterpenes. In vitro calli were induced from leaf explants of native plants and cultured in semi-solid medium under controlled conditions of humidity, temperature and photoperiod. The quinonemethide triterpenes showed maximum accumulation in the logarithmic phase growth of the cell culture. A rapid, sensitive and reliable reverse-phase HPLC method was used for quantitative determination of the antitumoral and antioxidant quinonemethide triterpenes, 22β-hydroxymaytenin and maytenin in callus of Maytenus ilicifolia. Well resolved peaks with good detection response and linearity in the range 1.0 - 100 µg/mL were obtained. This quantitative work was performed by an external standard method.

  • further sesquiterpene pyridine alkaloids from Maytenus aquifolium
    Phytochemistry, 1998
    Co-Authors: Joaquim Corsino, Ana Maria Soares Pereira, Suzelei C Franca, Vanderlan Da Silva Bolzani, Maysa Furlan
    Abstract:

    Abstract Two new sesquiterpene evoninate alkaloids, aquifoliunine E-III and aquifoliunine E-IV, were isolated from the root bark of Maytenus aquifolium . The structures of the new compounds were elucidated on the basis of spectroscopic methods, including ES-MS.

  • bioactive sesquiterpene pyridine alkaloids from Maytenus aquifolium
    Phytochemistry, 1998
    Co-Authors: Joaquim Corsino, Ana Maria Soares Pereira, Suzelei C Franca, Vanderlan Da Silva Bolzani, Maysa Furlan
    Abstract:

    Abstract Two new sesquiterpene evoninate alkaloids, were isolated together with the known compounds syringaresinol and 4′- O -methyl-(−)-epigallocatechin from the root bark of Maytenus aquifolium . The structures of the two alkaloids were elucidated by interpretation of their spectral data, and both exhibited very weak activity in a mechanism-based DNA-modifying yeast assay.

Osamu Shirota - One of the best experts on this subject based on the ideXlab platform.

Hiroshi Morita - One of the best experts on this subject based on the ideXlab platform.

Koichi Takeya - One of the best experts on this subject based on the ideXlab platform.

  • two cangorosin a type triterpene dimers from Maytenus chuchuhuasca
    Chemical & Pharmaceutical Bulletin, 2004
    Co-Authors: Osamu Shirota, Hiroshi Morita, Setsuko Sekita, Koichi Takeya, Motoyoshi Satake, Hideji Itokawa
    Abstract:

    : Two new cangorosin A type triterpene dimers, which composed of two triterpene units jointed by two ether linkages between the A and B rings, were isolated from the Brazilian medicinal plant "xuxua" (Maytenus chuchuhuasca). Structures of new isolates, xuxuasins A (1) and B (2), were established based on several spectroscopic evidences.

  • two new sesquiterpene pyridine alkaloids from Maytenus chuchuhuasca
    Heterocycles, 2004
    Co-Authors: Osamu Shirota, Hiroshi Morita, Setsuko Sekita, Koichi Takeya, Motoyoshi Satake, Hideji Itokawa
    Abstract:

    Two new sesquiterpene pyridine alkaloids, chuchuhuanines E-VI (1) and E-VII (2), were isolated from root barks of Maytenus chuchuhuasca Raymond-Hamet et Colas (Celastraceae). Their structures were elucidated by the analysis of spectral data.

  • New triterpene dimers from Maytenus ilicifolia
    Tetrahedron Letters, 2001
    Co-Authors: Hideji Itokawa, Hiroshi Morita, Osamu Shirota, Koichi Takeya, Nobuo Tomioka, Akiko Itai
    Abstract:

    Abstract Four new cytotoxic triterpene dimers from Maytenus ilicifolia were elucidated by spectroscopic and chemical evidences. Two of them were related to be atropisomer separated by a barrier of 32.8 kcal/mol and each stable conformer was elucidated by molecular mechanics calculation and NOE relationship.

  • new geometric and stereoisomeric triterpene dimers from Maytenus chuchuhuasca
    Chemical & Pharmaceutical Bulletin, 1998
    Co-Authors: Osamu Shirota, Hiroshi Morita, Koichi Takeya, Hideji Itokawa
    Abstract:

    New geometric and stereoisomeric triterpene dimers, 7, 8-dihydroisoxuxuarine Eα (2), xuxuarines Fβ (3), Gα (4) and Gβ (5), along with a known compound, scutidin αA (1), were isolated from the South American medicinal plant "xuxua" (Maytenus chuchuhuasca RAYMOND-HAMET et COLAS). Their structures were determined on the basis of spectroscopic evidence including CD spectral studies.

  • Five New Triterpene Dimers from Maytenus chuchuhuasca
    Journal of Natural Products, 1997
    Co-Authors: Osamu Shirota, Hiroshi Morita, Koichi Takeya, Hideji Itokawa
    Abstract:

    Five new triterpene dimers, named isoxuxuarines Aα (1), Aβ (2), 7,8-dihydroisoxuxuarine Aα (3), 7,8-dihydroxuxuarine Aα (4), and xuxuarine Eβ (5), were isolated from the South American medicinal plant “xuxua” (Maytenus chuchuhuasca). Their structures, representative of regiochemical and stereochemical isomers, were determined on the basis of spectroscopic evidence including CD spectral studies.

Hideji Itokawa - One of the best experts on this subject based on the ideXlab platform.

  • two cangorosin a type triterpene dimers from Maytenus chuchuhuasca
    Chemical & Pharmaceutical Bulletin, 2004
    Co-Authors: Osamu Shirota, Hiroshi Morita, Setsuko Sekita, Koichi Takeya, Motoyoshi Satake, Hideji Itokawa
    Abstract:

    : Two new cangorosin A type triterpene dimers, which composed of two triterpene units jointed by two ether linkages between the A and B rings, were isolated from the Brazilian medicinal plant "xuxua" (Maytenus chuchuhuasca). Structures of new isolates, xuxuasins A (1) and B (2), were established based on several spectroscopic evidences.

  • two new sesquiterpene pyridine alkaloids from Maytenus chuchuhuasca
    Heterocycles, 2004
    Co-Authors: Osamu Shirota, Hiroshi Morita, Setsuko Sekita, Koichi Takeya, Motoyoshi Satake, Hideji Itokawa
    Abstract:

    Two new sesquiterpene pyridine alkaloids, chuchuhuanines E-VI (1) and E-VII (2), were isolated from root barks of Maytenus chuchuhuasca Raymond-Hamet et Colas (Celastraceae). Their structures were elucidated by the analysis of spectral data.

  • New triterpene dimers from Maytenus ilicifolia
    Tetrahedron Letters, 2001
    Co-Authors: Hideji Itokawa, Hiroshi Morita, Osamu Shirota, Koichi Takeya, Nobuo Tomioka, Akiko Itai
    Abstract:

    Abstract Four new cytotoxic triterpene dimers from Maytenus ilicifolia were elucidated by spectroscopic and chemical evidences. Two of them were related to be atropisomer separated by a barrier of 32.8 kcal/mol and each stable conformer was elucidated by molecular mechanics calculation and NOE relationship.

  • new geometric and stereoisomeric triterpene dimers from Maytenus chuchuhuasca
    Chemical & Pharmaceutical Bulletin, 1998
    Co-Authors: Osamu Shirota, Hiroshi Morita, Koichi Takeya, Hideji Itokawa
    Abstract:

    New geometric and stereoisomeric triterpene dimers, 7, 8-dihydroisoxuxuarine Eα (2), xuxuarines Fβ (3), Gα (4) and Gβ (5), along with a known compound, scutidin αA (1), were isolated from the South American medicinal plant "xuxua" (Maytenus chuchuhuasca RAYMOND-HAMET et COLAS). Their structures were determined on the basis of spectroscopic evidence including CD spectral studies.

  • Five New Triterpene Dimers from Maytenus chuchuhuasca
    Journal of Natural Products, 1997
    Co-Authors: Osamu Shirota, Hiroshi Morita, Koichi Takeya, Hideji Itokawa
    Abstract:

    Five new triterpene dimers, named isoxuxuarines Aα (1), Aβ (2), 7,8-dihydroisoxuxuarine Aα (3), 7,8-dihydroxuxuarine Aα (4), and xuxuarine Eβ (5), were isolated from the South American medicinal plant “xuxua” (Maytenus chuchuhuasca). Their structures, representative of regiochemical and stereochemical isomers, were determined on the basis of spectroscopic evidence including CD spectral studies.