Detection of intestinal colonization of probiotic Lactobacillus rhamnosus by stool culture in modified selective media

ObjectiveTo develop an approach for making a selective and differential media specific for Lactobacillus rhamnosus Goldin and Gorbach (LGG) in order to distinguish it from other bacterial flora in fecal samples.MethodsThe current media referred as LGGM has been prepared by using MRS media ingredients (replacing dextrose with 2% sorbitol), and incorporation of nalidixic acid (40 μg/mL), bromocresol purple (0.002 %); the pH of the media was adjusted to 4.5.ResultsThe LGGM showed a greater colony forming units compared to MRS media. The growth of pure LGG strain was significantly greater in LGGM, and the recovery rate of LGG released from fecal samples (after oral feeding) was significantly greater (P<0.001).ConclusionsThus LGGM could be used as a potential media for the isolation and identification of LGG strain.