RESUMO
Curdlan from Agrobacterium sp. was oxidized using 2,2,6,6,-tetramethylpiperidine-1-oxyl radical (TEMPO)-NaBr-NaClO systems at pH 11. The effects of oxidation conditions on degrees of oxidation and polymerization of the products obtained were studied using SEC-MALLS, NMR and IR analyses. Different families of water-soluble beta-(1,3)-polyglucuronic and beta-(1,3)-polyglucoglucuronic acid sodium salts were quantitatively generated with a yield of 80% and without significant loss of their molecular weights. Given that beta-(1,3)-polyglucuronic acids prepared from the regioselective oxidation of curdlan by the TEMPO-NaBr-NaClO systems regularly consist of the glucuronic acid repeating unit; they may open new biotechnological fields for the utilizations of water soluble forms of curdlan.
Assuntos
Óxidos N-Cíclicos/farmacologia , Glucuronatos/química , Hipoclorito de Sódio/química , beta-Glucanas/química , Carboidratos/química , Óxidos N-Cíclicos/química , Eletroquímica/métodos , Concentração de Íons de Hidrogênio , Espectroscopia de Ressonância Magnética/métodos , Modelos Químicos , Peso Molecular , Oxigênio/química , Rhizobium/metabolismo , Espectrofotometria Infravermelho/métodos , Espectroscopia de Infravermelho com Transformada de Fourier , Água/químicaRESUMO
This paper studies the synthesis and properties of anionic and/or amphiphilic pullulan microparticles crosslinked with epichlorohydrine or with sodium trimethaphosphate. The polysaccharide gels were physicochemically characterized and their interaction with enzymes (lysozyme) was studied with the aim to appreciate the performances for separation/purification/immobilization of the enzymes or controlled release drug systems.
