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Updated: Jul 31, 2025
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Identification of Rare Bacterial Pathogens by 16S rRNA Gene Sequencing and MALDI-TOF MS
Published on: July 11, 2016
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The power of DNA based methods in probiotic authentication
Hanan R Shehata1,2, Steven G Newmaster1
1Natural Health Product Research Alliance, Department of Integrative Biology, College of Biological Science, University of Guelph, Guelph, ON, Canada.
Frontiers in Microbiology
|May 4, 2023
Summary
Quality control for probiotics is essential. Molecular methods confirmed the identity and accuracy of probiotic strains in a top-selling product, ensuring safety and efficacy for consumers.
Area of Science:
- Microbiology
- Molecular Biology
- Food Science
Background:
- The global probiotic market is expanding, necessitating robust quality control for product safety and efficacy.
- Assurance involves verifying probiotic strains, viable cell counts, and absence of contaminants.
- Third-party evaluation of probiotic quality and label accuracy is recommended.
Purpose of the Study:
- To evaluate the label accuracy of a top-selling multi-strain probiotic product.
- To confirm the presence and identity of specific probiotic strains using molecular methods.
Main Methods:
- Analysis of 55 samples (5 finished products, 50 raw ingredients) comprising 100 probiotic strains.
- Utilized targeted PCR, amplicon-based High Throughput Sequencing (HTS), and Shotgun Metagenomic Sequencing (SMS).
Main Results:
- Targeted PCR confirmed all strains/species; 40 identified to strain level, 60 to species level.
- HTS (V5-V8) showed ~99% reads matched target species; no undeclared species detected.
- HTS (V3-V4) showed ~2-3% reads matched undeclared *Proteus* species, but culturing confirmed absence of viable *Proteus*.
- SMS confirmed assembly of all 10 target strains' genomes in finished products.
Conclusions:
- Targeted methods offer quick, accurate identification of known taxa.
- Non-targeted methods (HTS, SMS) identify all species, including contaminants, but are complex and costly.
- Molecular techniques are crucial for ensuring probiotic product quality and label accuracy.
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