Microbiological Enumeration of Dietary Supplements and the Creation of a Sequence Database for the Microbiota Found in Functional Foods

Introduction: Understanding the health effects of the microbiome is at the forefront of many current scientific studies.  Modulating the microbiome has the potential to improve the health of both the intestinal tract and the immune system, as well as, enhance the bioavailability of nutrients. Probiotics are “live microorganisms which, when administered in adequate amounts, confer health benefits on the host.”  The popularity of these products has grown exponentially over the past few years.

Purpose: Recent studies demonstrated that a daily intake of at least 10⁷ to 10⁹ viable probiotic cells is necessary to obtain sufficient colonization within the gut. The viability of microbes within dietary supplements is equally important as the current review criteria for a given product. This process consists of strain taxonomy, antibiotic resistance, extent of use in foods, and source of that particular strain.

Methods: We have tested ten supplements. Each product was plated and grown in both aerobic and anaerobic conditions using several different types of media.  Colonies are counted using a colony counter and expressed in CFU/ml. Colonies isolated from these plates were identified using custom designed primers and whole genome sequencing.

Results: Nine of the ten products tested support the manufacturer’s viability claims. We have also isolated a contaminant, Enterococcus faecium, from one of the products. We are being proactive in testing probiotic viability and creating a whole genome database for microbial ingredients to substantiate the manufacturer’s labeling claims.

Significance: The effectiveness of probiotics is not regulated; however, proper labeling will help ensure consumer safety.  These data help FDA monitor these supplements to ensure accuracy of manufacturer labeling and product safety in an effort to protect the consumer.