Study on the functional properties of potential indigenous probiotics isolated from human samples in West Africa

A study was performed to isolate and evaluate potential indigenous probiotic strains in Ghana. A total of 99 strains were isolated from human breast milk (n = 29) and fecal samples (n = 70), which were identified and characterized using methods ranging from plating growth tests and presumptive analysis at species level using MALDI-TOF MS, prior to validation through 16S rRNA gene sequence analysis. Gastrointestinal tolerance and ability to form biofilms in vitro were determined. Results indicated that out of 99 isolates, 25 were Gram-positive, catalase-negative rods. More than one-third was identified as Lactobacillus fermentum. Others were identified to be Lactobacillus (plantarum, rhamnosus, salivarius, reuteri), Enterococcus faecium, Weissella spp. and Pediococcus spp. Among the 25 isolates, 9 had activity against both Gram-negative and Gram-positive pathogens including reference or local clinical isolates of Pseudomonas aeruginosa, Salmonella Typhi, Staphylococcus aureus and Escherichia coli. Almost all isolates were effective against P. aeruginosa, E. coli and S. Typhi. Thirteen isolates did not show activity towards S. aureus. The isolates were more effective against local pathogens tested than nonindigenous pathogens. The data showed survival of all studied isolate at pH 2, 3 and 6 followed by a successful growth of the co-cultured biofilm in a 3D Alvatex platform.