Antioxidant and immunomodulatory activity of selenium exopolysaccharide produced by Lactococcus lactis subsp. lactis

► EPS and Se-EPS of Lactococcus lactis subsp. lactis was prepared. ► Se-EPS was synthesized successfully and did not show drug-induced physical signs. ► Antioxidant activity and immunomodulatory activity of EPS and Se-EPS was compared. ► Se-EPS had higher antioxidant activity and immunomodulatory activity than EPS.