Sulfonation and anticoagulant activity of fungal exocellular β-(1→6)-d-glucan (lasiodiplodan)

Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-27T11:28:27Z No. of bitstreams: 0 Made available in DSpace on 2014-05-27T11:28:27Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-02-15 An exocellular β-(1→6)-d-glucan (lasiodiplodan) produced by a strain of Lasiodiplodia theobromae (MMLR) grown on sucrose was derivatized by sulfonation to promote anticoagulant activity. The structural features of the sulfonated β-(1→6)-d-glucan were investigated by UV-vis, FT-IR and 13C NMR spectroscopy, and the anticoagulant activity was investigated by the classical coagulation assays APTT, PT and TT using heparin as standard. The content of sulfur and degree of substitution of the sulfonated glucan was 11.73% and 0.95, respectively. UV spectroscopy showed a band at 261 nm due to the unsaturated bond formed in the sulfonation reaction. Results of FT-IR and 13C NMR indicated that sulfonyl groups were inserted on the polysaccharide. The sulfonated β-(1→6)-d-glucan presented anticoagulant activity as demonstrated by the increase in dose dependence of APTT and TT, and these actions most likely occurred because of the inserted sulfonate groups on the polysaccharide. The lasiodiplodan did not inhibit the coagulation tests. © 2012 Elsevier Ltd. Depto de Física, Química e Biologia Universidade Estadual Paulista-UNESP, CEP 19060-900, Presidente Prudente, São Paulo Biorefining Research Institute Lakehead University, Thunder Bay, ON P7B 5E1 Depto de Bioquímica e Biologia Molecular Universidade Federal Do Paraná, CEP 81531-980, Curitiba, Paraná Laboratório de Tecido Conjuntivo Hospital Universitário Clementino Fraga Filho Universidade Federal Do Rio de Janeiro, CEP 21941-590, Rio de Janeiro, RJ Depto de Física, Química e Biologia Universidade Estadual Paulista-UNESP, CEP 19060-900, Presidente Prudente, São Paulo