In our study, sarecycline demonstrated less activity compared to minocycline against isolates from the Bacteroidetes phylum including a number of beneficial strains such as Bacteroides fragilis nontoxigenic and Bacteroides vulgatus.Bacteroides fragilis nontoxigenic is a member of the gut microbiota that was recently proposed to be a potential probiotic because of its protective function against colitis using the CD4 + CD45Rb transfer model of experimental colitis [40]. The gene discussed is CD4; the disease is colitis.