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Ya-ting Liu - One of the best experts on this subject based on the ideXlab platform.

Jaume Bastida - One of the best experts on this subject based on the ideXlab platform.

  • Glycosylated narciclasine alkaloid in Hippeastrum puniceum (Lam.) Kuntze
    South African Journal of Botany, 2020
    Co-Authors: Amanda Eiriz Feu, Jaume Bastida, Jean Paulo De Andrade, Alejandro Ayala, Larissa Costa De Almeida, Letícia V. Costa-lotufo, Javier Ellena, Warley De Souza Borges
    Abstract:

    Abstract The present work focused on the chemical study of the main alkaloid component in Brazilian indigenous Amaryllidaceae species Hippeastrum puniceum (Lam.) Kuntze. The strategy applied was based on a distinct partitioning process and chromatographic-purification steps using the crude methanolic extract as the starting material. In this way, the glycosylated derivative narciclasine-4-O-β-D-xylopyranoside was isolated from the ethyl acetate fraction of H. puniceum. Structural elucidation of the compound was performed through NMR (Nuclear Magnetic Resonance) analysis including mono- and bi-dimensional experiments. The absolute configuration was determined herein for the first time by means of X-Ray Crystallography. The compound was also evaluated as cytotoxic agent against colon (HCT 116) and breast (MCF-7) tumor cells, showing no significant activity at the tested concentrations of 10 and 50 μM.

  • Hippeastrum reticulatum amaryllidaceae alkaloid profiling biological activities and molecular docking
    Molecules, 2017
    Co-Authors: Luciana R Tallini, Warley De Souza Borges, Edison Osorio, Vanessa Dias Dos Santos, Marcel Kaiser, Jose Angelo S Zuanazzi, Jaume Bastida
    Abstract:

    The Amaryllidaceae family has proven to be a rich source of active compounds, which are characterized by unique skeleton arrangements and a broad spectrum of biological activities. The aim of this work was to perform the first detailed study of the alkaloid constituents of Hippeastrum reticulatum (Amaryllidaceae) and to determine the anti-parasitological and cholinesterase (AChE and BuChE) inhibitory activities of the epimers (6α-hydroxymaritidine and 6β-hydroxymaritidine). Twelve alkaloids were identified in H. reticulatum: eight known alkaloids by GC-MS and four unknown (6α-hydroxymaritidine, 6β-hydroxymaritidine, reticulinine and isoreticulinine) by NMR. The epimer mixture (6α-hydroxymaritidine and 6β-hydroxymaritidine) showed low activity against all protozoan parasites tested and weak AChE-inhibitory activity. Finally, a molecular docking analysis of AChE and BuChE proteins showed that isoreticulinine may be classified as a potential inhibitory molecule since it can be stabilized in the active site through hydrogen bonds, π-π stacking and hydrophobic interactions.

  • alkaloids from Hippeastrum argentinum and their cholinesterase inhibitory activities an in vitro and in silico study
    Journal of Natural Products, 2016
    Co-Authors: Javier E Ortiz, Jaume Bastida, Natalia B Pigni, Sebastian A Andujar, German Roitman, Fernando D Suvire, Ricardo D Enriz, Alejandro Tapia, Gabriela Egly Feresin
    Abstract:

    Two new alkaloids, 4-O-methylnangustine (1) and 7-hydroxyclivonine (2) (montanine and homolycorine types, respectively), and four known alkaloids were isolated from the bulbs of Hippeastrum argentinum, and their cholinesterase-inhibitory activities were evaluated. These compounds were identified using GC-MS, and their structures were defined by physical data analysis. Compound 2 showed weak butyrylcholinesterase (BuChE)-inhibitory activity, with a half-maximal inhibitory concentration (IC50) value of 67.3 ± 0.09 μM. To better understand the experimental results, a molecular modeling study was also performed. The combination of a docking study, molecular dynamics simulations, and quantum theory of atoms in molecules calculations provides new insight into the molecular interactions of compound 2 with BuChE, which were compared to those of galantamine.

  • Identification of Alkaloids from Hippeastrum aulicum (Ker Gawl.) Herb. (Amaryllidaceae) Using CGC-MS and Ambient Ionization Mass Spectrometry (PS-MS and LS-MS)
    Journal of the Brazilian Chemical Society, 2016
    Co-Authors: Carliani Dal Piero B. Bessa, Jaume Bastida, Jean Paulo De Andrade, Renata Biella Salles De Oliveira, Eloilson Domingos, Heloa Santos, Wanderson Romão, Warley De Souza Borges
    Abstract:

    Amaryllidaceae alkaloids are well-known isoquinolines which have demonstrated a wide range of biological activities such as antiviral, anticancer, acetylcholinesterase inhibition, antimalarial, among others. Mass spectrometry (MS) studies based on capillary gas chromatography (CGC), paper spray (PS), and leaf spray (LS) ionization were carried out for alkaloid investigation of the native Brazilian species Hippeastrum aulicum, along with nuclear magnetic resonance (NMR) techniques. Thirty-one alkaloids were identified including the new compound haemanthamine N-oxide. The results from PS- and LS-MS techniques were consistent with those observed in CGC-MS analysis. To the best of our knowledge, it is the first study combining NMR, CGC-MS and the ambient ionization-mass spectrometry (PS- and LS-MS) on Amaryllidaceae plants.

  • New lycosinine derivative from Hippeastrum breviflorum
    Revista Brasileira de Farmacognosia, 2015
    Co-Authors: Camila Sebben, Strahil Berkov, Jaume Bastida, Jean Paulo De Andrade, Raquel Brandt Giordani, Edison Javier Osorio, Marcos Sobral, Mauro Vieira De Almeida, Amélia Teresinha Henriques, Jose Angelo S Zuanazzi
    Abstract:

    A new lycosinine derivative, 9-O-demethyllycosinine B, was isolated from the native Brazilian Hippeastrum breviflorum Herb., Amaryllidaceae, along with the well-known alkaloids lycosinine B and lycorine. The structure of the new compound was established by physical and spectroscopic methods. 9-Odemethyllycosinine B is the third lycosinine variant identified in the Amaryllidaceae family.

Werner Döpke - One of the best experts on this subject based on the ideXlab platform.

Annemieke Vandamme - One of the best experts on this subject based on the ideXlab platform.

  • profile of resistance of human immunodeficiency virus to mannose specific plant lectins
    Journal of Virology, 2004
    Co-Authors: Annemieke Vandamme, Kurt Vermeire, Sigrid Hatse, Els J. M. Van Damme, Willy J Peumans, Kristel Van Laethem
    Abstract:

    The mannose-specific plant lectins from the Amaryllidaceae family (e.g., Hippeastrum sp. hybrid and Galanthus nivalis) inhibit human immunodeficiency virus (HIV) infection of human lymphocytic cells in the higher nanogram per milliliter range and suppress syncytium formation between persistently HIV type 1 (HIV-1)-infected cells and uninfected CD4+ T cells. These lectins inhibit virus entry. When exposed to escalating concentrations of G. nivalis and Hippeastrum sp. hybrid agglutinin, a variety of HIV-1(IIIB) strains were isolated after 20 to 40 subcultivations which showed a decreased sensitivity to the plant lectins. Several amino acid changes in the envelope glycoprotein gp120, but not in gp41, of the mutant virus isolates were observed. The vast majority of the amino acid changes occurred at the N glycosylation sites and at the S or T residues that are part of the N glycosylation motif. The degree of resistance to the plant lectins was invariably correlated with an increasing number of mutated glycosylation sites in gp120. The nature of these mutations was entirely different from that of mutations that are known to appear in HIV-1 gp120 under the pressure of other viral entry inhibitors such as dextran sulfate, bicyclams (i.e., AMD3100), and chicoric acid, which also explains the lack of cross-resistance of plant lectin-resistant viruses to any other HIV inhibitor including T-20 and the blue-green algae (cyanobacteria)-derived mannose-specific cyanovirin. The plant lectins represent a well-defined class of anti-HIV (microbicidal) drugs with a novel HIV drug resistance profile different from those of other existing anti-HIV drugs.

Jean Paulo De Andrade - One of the best experts on this subject based on the ideXlab platform.

  • Glycosylated narciclasine alkaloid in Hippeastrum puniceum (Lam.) Kuntze
    South African Journal of Botany, 2020
    Co-Authors: Amanda Eiriz Feu, Jaume Bastida, Jean Paulo De Andrade, Alejandro Ayala, Larissa Costa De Almeida, Letícia V. Costa-lotufo, Javier Ellena, Warley De Souza Borges
    Abstract:

    Abstract The present work focused on the chemical study of the main alkaloid component in Brazilian indigenous Amaryllidaceae species Hippeastrum puniceum (Lam.) Kuntze. The strategy applied was based on a distinct partitioning process and chromatographic-purification steps using the crude methanolic extract as the starting material. In this way, the glycosylated derivative narciclasine-4-O-β-D-xylopyranoside was isolated from the ethyl acetate fraction of H. puniceum. Structural elucidation of the compound was performed through NMR (Nuclear Magnetic Resonance) analysis including mono- and bi-dimensional experiments. The absolute configuration was determined herein for the first time by means of X-Ray Crystallography. The compound was also evaluated as cytotoxic agent against colon (HCT 116) and breast (MCF-7) tumor cells, showing no significant activity at the tested concentrations of 10 and 50 μM.

  • Identification of Alkaloids from Hippeastrum aulicum (Ker Gawl.) Herb. (Amaryllidaceae) Using CGC-MS and Ambient Ionization Mass Spectrometry (PS-MS and LS-MS)
    Journal of the Brazilian Chemical Society, 2016
    Co-Authors: Carliani Dal Piero B. Bessa, Jaume Bastida, Jean Paulo De Andrade, Renata Biella Salles De Oliveira, Eloilson Domingos, Heloa Santos, Wanderson Romão, Warley De Souza Borges
    Abstract:

    Amaryllidaceae alkaloids are well-known isoquinolines which have demonstrated a wide range of biological activities such as antiviral, anticancer, acetylcholinesterase inhibition, antimalarial, among others. Mass spectrometry (MS) studies based on capillary gas chromatography (CGC), paper spray (PS), and leaf spray (LS) ionization were carried out for alkaloid investigation of the native Brazilian species Hippeastrum aulicum, along with nuclear magnetic resonance (NMR) techniques. Thirty-one alkaloids were identified including the new compound haemanthamine N-oxide. The results from PS- and LS-MS techniques were consistent with those observed in CGC-MS analysis. To the best of our knowledge, it is the first study combining NMR, CGC-MS and the ambient ionization-mass spectrometry (PS- and LS-MS) on Amaryllidaceae plants.

  • New lycosinine derivative from Hippeastrum breviflorum
    Revista Brasileira de Farmacognosia, 2015
    Co-Authors: Camila Sebben, Strahil Berkov, Jaume Bastida, Jean Paulo De Andrade, Raquel Brandt Giordani, Edison Javier Osorio, Marcos Sobral, Mauro Vieira De Almeida, Amélia Teresinha Henriques, Jose Angelo S Zuanazzi
    Abstract:

    A new lycosinine derivative, 9-O-demethyllycosinine B, was isolated from the native Brazilian Hippeastrum breviflorum Herb., Amaryllidaceae, along with the well-known alkaloids lycosinine B and lycorine. The structure of the new compound was established by physical and spectroscopic methods. 9-Odemethyllycosinine B is the third lycosinine variant identified in the Amaryllidaceae family.

  • Crinine-type alkaloids from Hippeastrum aulicum and H. calyptratum
    Phytochemistry, 2014
    Co-Authors: Jean Paulo De Andrade, Francesc Viladomat, Carles Codina, Ying Guo, Mercè Font-bardia, Teresa Calvet, Jullie Dutilh, Jose Angelo S Zuanazzi
    Abstract:

    An ongoing search for alkaloids in the Amaryllidaceae species using GC–MS resulted in the identification of two crinine-type alkaloids, aulicine (1) and 3-O-methyl-epimacowine, (2) from the indigenous Brazilian species Hippeastrum aulicum and Hippeastrum calyptratum, respectively. In addition, two alkaloids, 11-oxohaemanthamine (3) and 7-methoxy-O-methyllycorenine (4) were both isolated from H. aulicum. Furthermore, we provide here complete NMR spectroscopic data for the homolycorine analogues nerinine (5) and albomaculine (6). The absolute stereochemistry of the 5,10b-ethano bridge in the crinine variants was determined by circular dichroism and X-ray crystallographic analysis, thus presenting the first direct evidence for the presence of crinine-type alkaloids in the genus Hippeastrum.

  • alkaloids from the Hippeastrum genus chemistry and biological activity
    Revista Latinoamericana de Química, 2012
    Co-Authors: Jean Paulo De Andrade, Strahil Berkov, Carles Codina, Ying Guo, Jose Angelo S Zuanazzi, Natalia B Pigni, Laura Torrasclaveria, Ricardo Reyeschilpa, Abdelaziz El Amrani, Francesc Viladomat
    Abstract:

    In recent years alkaloids from the genus Hippeastrum have been shown to exhibit a broad spectrum of biological activities, including antiparasitic, antiproliferative, apoptosis-induced, psychopharmacological, acetylcholinesterase-inhibitory, among others. This work presents a brief chemical and biological review of the alkaloids found in the genus Hippeastrum. www.relaquim.com