Yazar "Abbaskhan, Ahmed" seçeneğine göre listele

Listeleniyor 1 - 2 / 2
  • Küçük Resim Yok
    Öğe
    Cellular reactive oxygen species inhibitory constituents of Hypericum thasium Griseb
    (Pergamon-Elsevier Science Ltd, 2009) Demirkiran, Ozlem; Mesaik, M. Ahmed; Beynek, Hayrettin; Abbaskhan, Ahmed; Choudhary, M. Iqbal
    The phytochemical investigation of the ethyl acetate extract of Hypericum thasium has led to the characterization of four benzophenone derivatives 1-4, a known benzophenone 5 and four known flavonoids, quercetin (6), quercitrin (7), isoquercetin (8), and 3, 8-biapigenin (9). Lucigenin- and luminal-based chemiluminescence assays were employed to monitor the inhibitory activity of these compounds towards the production of reactive oxygen species (ROS) by human polymorphoneutrophils (PMNs). The assay results showed that benzophenones 1 and 3 are extracellular inhibitors of ROS production, while flavonoids 6, 8, and 9 can modulate intracellular ROS production. (C) 2008 Elsevier Ltd. All rights reserved.
  • Küçük Resim Yok
    Öğe
    Immunosupressive Phenolic Constituents from Hypericum montbretii Spach.
    (Acg Publications, 2013) Demirkiran, Ozlem; Mesaik, M. Ahmad; Beynek, Hayrettin; Abbaskhan, Ahmed; Choudhary, M. Iqbal
    The MeOH extract of aerial parts of H. monbretii Spach. have yielded quercetin (1), kaempferol (2), quercitrin (3), hyperin (4), myricitrin (5), rutin (6), I 3 II 8 '' biapigenin (7), methyl chlorogenate (8), 5-O-p-coumaroylquinic acid (9), and chlorogenic acid (5-O-caffeoyl quinic acid) (10), mangiferin (11), and shikimic acid (12). Three compounds 1, 2 and 4 were found to have an immunomodulating inhibitory activity on the oxidative burst response of human neutrophils, as well on mouse peritoneal macrophages. Effects of compounds on whole blood phagocytes activity was found to be with IC50 ranging between 8.0-12.2 mu g/mL. Only compounds 1, and 2 were found to interfere with T-cell proliferation, and IL-2 release in PHA activated peripheral blood mononuclear cells system. To the best of our knowledge, this is the first report of phytochemical and biological activity study on H. montbretii Spach.