Genomic interrogation of commercial infant probiotic products for label accuracy.

objectiveTo evaluate the label accuracy of commercial infant probiotic products and identify potential microbial contamination.

methodsDNA was extracted from seventeen infant probiotic products purchased from a large online vendor. Samples underwent 16S ribosomal RNA gene sequencing, QIIME analysis, and bacterial taxonomic classification. Identified bacterial species were compared with product labels for label accuracy and potential contaminants. Additionally, fungal DNA was amplified using qPCR with universal 18S fungal primers, and cultures were performed to assess viability.

resultsOver 82% of bacterial DNA extracted from samples corresponded to species listed on product labels. Contaminating bacteria were closely related species. Lot-to-lot variation in bacterial species abundance was greater in multi-strain products compared with single-strain products. Fungal DNA was detected in some samples, but culture results indicated these organisms were not viable.

conclusionsThis pilot study highlights that most bacterial species in commercial infant probiotic products are accurately represented on labels. Single-strain products reliably match product labels whereas multi-strain products were more prone to variation of species abundance and species omission. Additionally, fungal contamination of limited samples was not viable. These findings emphasize the need for improved regulatory guidelines and standardization of probiotic products, particularly those marketed for infants. IMPACT: Commercial infant probiotic products were interrogated for label accuracy using 16S ribosomal RNA sequencing. Most bacterial species in commercial infant probiotic products are accurately represented on labels without pathogenic bacterial contamination. Live fungal contamination is absent. To date, no studies have interrogated infant probiotic products on this scale (other studies have been limited to single or dual strain infant probiotics). Since probiotics lack FDA regulation, this pilot study provides important information for pediatricians and consumers, further highlighting the need for improved quality control and standardization of probiotics.