Production, purification, and structural characteristics of extracellular polysaccharides derived from Lactobacillus acidophilus

•The optimal concentrations of sucrose, yeast extract and polysorbate 80 were 10.15 g/L, 25 g/L and 2 g/L respectively for producing EPSs.•The optimal EPS production was 923.7 mg/L.•The EPS production occurred at the late stationary phase from 72 h to 120 h.•The purification approach was able to remove 99.9% proteins and 98.5% of nucleic acid.•EPSs consisted of mannose, ribose, glucose and galactose in ratios of 60.0: 22.8: 15.0: 2.2.