Journal of Probiotics & Health
Open Access

Abstract

Specific TaqMan® Probes for the Identification and Quantification of Lactobacilli in Pharmaceuticals

Herbel SR, Von Nickisch-Rosenegk M, Kuhn M, Murugaiyan J, Wieler LH and Guenther S

Several probiotic products containing species of the genus Lactobacillus are available on the market. Usually, these are fermented dairy products such as yoghurts and vegetables. Additionally, probiotic bacteria are used in pharmaceuticals, which are also believed to have beneficial effects on human health. Common pharmaceutical application forms to deliver probiotics are tablets, drops or granulate formulations for oral administration. They should contain sufficient numbers of viable probiotics to assure active health benefits. Despite the successful commercialization of lactobacilli, their traditional species identification methods are time-consuming and laborintensive and do not allow quantification of the species. Therefore, the objective of the present work was to develop a culture independent, fast identification and quantification method for two commercially important species of the genus Lactobacillus (L. acidophilus and L. reuteri). We used a TaqMan® real time PCR assay based on the GroEL heat shock protein region. Therefore universal lactobacilli primers and species-specific TaqMan® primers have been developed. The assay allowed an unambiguous species-specific detection of L. acidophilus and L. reuteri from bacterial cultures as well as directly from tablets. Using this assay, we were able to detect lactobacilli strains to a level of 104 cfu/ml, which is a sufficient detection limit as commercial pharmaceuticals usually contain 108–1010 cfu/tablet of probiotic strains.