Effects of oral administration of yogurt fermented with Lactobacillus delbrueckii ssp. bulgaricus OLL1073R-1 and its exopolysaccharides against influenza virus infection in mice

► Yogurt fermented with L. bulgaricus OLL1073R-1 exerted anti-influenza virus effect in mice. ► Exopolysaccharide (EPS) from 1073R-1 also showed the antiviral activity in mice. ► Yogurt and EPS augmented antiviral antibodies in lung and NK cell activity of spleen cells. ► Acidic EPS fractionated from the EPS showed anti-influenza virus activity in mice.