Microbial goldmine: Investigating probiotic floral diversity in human breast milk

Abstract

Breast milk contains many bacteria to shapes the newborn's gut microbiota. Breastfeeding benefits the newborn health due to beneficial bacteria present inside the human milk. Thus the present study targets to examine the diversity of isolated probiotic flora residing in human milk associating with enhanced infant's health and to be used in milk formula as a possible candidates. From eleven healthy lactating mothers the milk samples were collected and the isolated bacteria were then enumerated on L-cystein augmented MRS (de Man Rogosa & Sharpe) media, the prophologically distinguishable colonies were then identified using biochemical (API-50 CH Kit) and 16S DNA sequence identification methods. Fifty diverse bacteria belonging to three bacterial genera (Staphylococcus, Streptococcus, and Bacillus) were obtained. Phylogenetic analysis was done for carbohydrate fermentation patrens using R programing and for 16S DNA sequence variations using Molecular Evolutionary Genetics Analysis Tool (MEGA) to cluster the isolates together. Tolerance of the isolated strain in gastrointestinal environment is also analised depicting endurance of the isolated potential probiotics in artificially simulated gastric juice (pH 2) and 0.3% bile salt concentration. In conclusion, an exclusive microbiota harbored by breast milk comprised mainly of Staphylococcus hominis, Staphylococcus epidermidis, Streptococcus salivaries, and Streptococcus lactarius. The flora colonize the newborn's gut and become an important probiotic source used in the simulated mother's milk formula. Therefore, human milk could be a good source of probiotics for infants.