Identification of a Peptide Produced by Bifidobacterium longum CECT 7210 with Antirotaviral Activity

Chenoll, Empar; Casinos, Beatriz; Bataller, Esther; Buesa, Javier; Ramón, Daniel; Genovés, Salvador; Fábrega, Joan; Rivero Urgell, Montserrat; Moreno Muñoz, José A.

Assays were carried out as in Muñoz et al. (2011) . Competition assays were performed with rotavirus SA11, Ito, VA70 and Wa in both HT-29 and MA-104 cell lines. In all cases, cell monolayers were grown in 96-well plates and the tested compounds were incubated with rotavirus followed by the infection of the cells with this virus-compound mixture (strategy A) or the compound was incubated with the cell cultures followed by the inoculation of the virus (strategy B). In both cases, viral antigens were detected by immunoperoxidase assays (Muñoz et al., 2011) . Infectious peroxidase-stained foci were counted and arithmetic means were calculated to determine the number of foci per microscopic field, which were compared with the number of infectious foci of untreated virus controls to obtain the reduction percentage of virus focus-forming units. The identified peptide was synthesized at 90% purity (Genscript Corporation, Piscataway, NJ, USA) and its activity was measured for both strategies at different concentrations (1, 5, 10, and 50 µM).