Synthesis and antioxidant activity evaluation of novel broom and cotton fibers derivatives



Novel antioxidant biopolymers composed by broom or cotton fibers, and trans-ferulic acid, α-lipoic acid, and α-tocopherol, were prepared. The acids were directly linked to fibers microfibrils hydroxylic groups using N,N-dimethylacetamide/lithium chloride (DMAc/LiCl) as solvent with dicyclohexylcarbodiimide (DCC) and N,N-dimethylaminopyridine (DMAP). Broom or cotton tocopherulate were prepared in the same conditions by using carboxylated fibers. Ester linkages were confirmed by using Fourier transformed infrared spectroscopy; biopolymers substitution degrees (DS) were determined by volumetric analysis. Antioxidant activity in inhibiting lipid peroxidation, in rat-liver microsomal membranes, induced in vitro by two different sources of free radicals, 2,2′-azobis (2-amidinopropane) (AAPH) and tert-butyl hydroperoxide (tert-BOOH), was evaluated. Finally, biocompatibility of these biomaterials was also tested by controlling glutathione-S-transferase (GST) basal concentrations. Our results strongly suggested that the better derivatives were the ferulate ones. However, all obtained biomaterials, showing excellent antioxidant properties and biocompatibility, could be successfully applied in biomedical and in packaging areas. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009