Probiotics analysis by high-throughput sequencing revealed multiple mismatches at bacteria genus level with the declared and actual composition

Abstract

The unregulated probiotic market can lead to serious health consequences. The aim of this study was to analyze commercially available probiotics using high-throughput sequencing. Nine out of seventeen probiotics contained all the bacterial genera declared by the manufacturer, however, in addition to them, extraneous genera of bacteria were found. The most common genus of bacteria in the studied samples was Lactobacillus. Representatives of this genus were declared in more than 80% of probiotics. 29% of probiotics were characterized by the absence of a microorganisms declared by the manufacturers. In three samples, Bifidobacterium spp. were absent, in one – Propionibacterium sp., and one probiotics did not contain the declared genus Bacillus. More than 70% of probiotics contained additional genera of bacteria not declared in the composition, among which the most common were Lacticaseibacillus sp., Lactiplantibacilus sp. and Enterococcus sp. One probiotic had completely different genera of bacteria in composition. Changes in the bacterial composition of probiotics can negatively affect the taste, storage, transportation of products and, most importantly, the health benefits of the supplement for humans. We have shown that high-throughput sequencing can be an effective tool for quality control of probiotic.