Quaternization of angico gum and evaluation of anti-staphylococcal effect and toxicity of their derivatives.

Modified polysaccharides have been featured as new agents against bacterial infection presenting biocompatibility in their use for medical purposes. In this work, we carried out the quaternization of Angico gum (AG). Quaternized Angico gum derivatives (QAG) were produced using a cationic moiety (3-Chloro-2-hydroxypropyl)trimethylammonium chloride onto the gum backbone. The products were characterized by FT-IR spectroscopy, Zeta potential, elemental analysis, and 1H NMR and degree of substitution (DS) was calculated. QAG were also evaluated for their anti-staphylococcal activity by determining Minimum Inhibitory and Bactericidal concentrations against pathogenic Staphylococcus spp. and by imaging using Atomic Force Microscopy. The hemolysis test and Galleria mellonella model were used to assess toxicity of gums. Our results showed that derivatives who presented highest DS (QAG-A3, 0.48 and QAG-B, 0.54) showed more effective antibacterial activity against tested bacteria, biocompatibility with erythrocytes and non-toxicity in G. mellonella model.