Physicochemical and biosorption properties of novel exopolysaccharide produced by Enterococcus faecalis

Duck intestinal homogenate isolate Enterococcus faecalis DU10 produced exopolysaccharide (EPS) (840 mg/L) in MRS medium (35 degrees C, pH 6.5), was characterized for its physicochemical, biosorption, antioxidant, antibiofilm and rheological properties. HPTLC analysis revealed fructose and arabinose are as major, xylose and mannose are as minor constituents of EPS. And further, this EPS DU10 was characterized through FTIR, H-1 and C-13 NMR. EPS DU10 efficiently adsorbed heavy metals Zn(II) (515.78 +/- 0.7 mg/g), Pb(II) (424.42 +/- 0.9 mg/g), Cd(II) (334.4 +/- 14 mg/g), and Cu(II) (232.9 +/- 0.3 mg/g). EPS DU10 exhibits broad spectrum of biofilm inhibition for bacterial pathogens and good in vitro antioxidant properties by scavenging free radicals at very low concentration (0.1 mg/mL). Along with these properties, high viscosity of EPS makes it suitable for pharmaceutical and industrial applications. (C) 2016 Elsevier Ltd. All rights reserved.