Described in the instant application are methods and compositions for support therapy in antitumor chemotherapeutic treatments, in acquired immunodeficiency syndrome treatments and in leukemia treatments. Said methods and compositions comprise a bacterial strain belonging to the species Lactobacillus pentosus and having an antiviral and an antibacterial activity, and a highly bioavailable zinc internalized in a tyndalized bacterial cell mixed with at least one rubber, and in particular an alginate and/or a gel, and in particular a gel.
