Effects of extraction methods on the composition and molar mass distributions of exopolymeric substances of the bacterium Sinorhizobium meliloti

► We study EPS from wild type and exoY strains of bacterium Sinorhizobium meliloti. ► EPS extracted by centrifugation, EDTA and formaldehyde/NaOH were compared. ► Two major components of proteinaceous and polysaccharide nature were found. ► Extraction methods influenced TOC, TN and total protein content in EPS. ► Molar mass distributions also differed among treatments and bacterial strains.