Guidelines for Validation of Qualitative Real-Time PCR Methods for Molecular Diagnostic Identification of Probiotics.

Probiotics have been shown to benefit human health through several mechanisms, including their role in improving the health of our gastrointestinal tracts. The health benefits of probiotics are strain specific, and therefore it is critical to include the correct strains in probiotic products when claiming specific health benefits. Several studies have reported issues concerning the accuracy of labeling of commercial probiotic products, including inaccurate taxonomy, missing species, or undeclared species. Consequently, there is a growing need to develop and validate assays to reliably verify strain identity in commercial probiotic products. PCR-based methods are the most commonly used methods for food species ingredient diagnostics because they are simple, fast, sensitive, and can be validated. The aim of this paper is to set the guidelines for validating targeted qualitative real-time PCR assays to verify the presence of specific strains in a probiotic supplement. Qualitative real-time PCR assays are validated to evaluate the assay performance in terms of specificity, sensitivity, repeatability, and reproducibility in detecting target strains. Setting these guidelines will facilitate and streamline the validation process for qualitative real-time PCR-based assays for probiotic identity authentication in support of quality assurance systems.