Lasiodiplodana (1→6)-β-D-Glucana: bioprodução, obtenção de moléculas derivatizadas por sulfonação e caracterização

Abstract

Microbial polysaccharides are macromolecules whose industrial interest has grown considerably in terms of their biological and technological properties. Among these, there are the β-glucans, which have shown different biological features, including anticoagulant properties, antioxidant, antiviral and anticarcinogenic. In addition to presenting potential in the treatment of cardiovascular diseases, diabetes and dyslipidemias. Chemical modifications in the primary structure of these macromolecules have been shown to be an important tool in potentiation of their biological functions, and of the modifications described in the scientific literature has sulfonation where sulphonates groups (S+O2OH) are inserted in their structure. In this context, the present study Lasiodiplodia ((1→6)-β-D-glucan) produced by the fungus Lasiodiplodia theobromae MMPI was derivatized by sulfonation. This modification was conducted using dimethyl sulfoxide as a solvent (Me2SO) and pyridine as catalyst. The sulfonate groups that replace hydroxyl groups in the molecule, were obtained by derivatizing agent chlorosulfonic acid. The sulfonation conditions led to obtain a derivative with degree of substitution of 0,24. Analysis by FT-IR confirmed the introduction of sulfonate groups in the primary structure of the glucan, and verified the appearance three characteristic bands at wavelengths 1186 cm-1 and 1240 cm-1 , which correspond to symmetric stretching vibration and asymmetric (strong) S=O, respectively, and the band in the region of 810 cm-1 , indicative symmetric vibration C-O-S, associated with the group C-O-SO3. Scanning electron microscopy showed morphological changes in the polymeric macrostructure of lasiodiplodana after derivatization, with the emergence of microfibrils along the structure and XRD analysis showed the appearance of regions with a certain molecular organization after derivatization with emergence peaks at 11,64°, 19,63°, 29,15° e 31, 15° at 2.