title: [Phenotypic and genotypic characterization of probiotic bacterial strains used in medicinal products].
abstract: BACKGROUND
  The optimization of quality testing strategy of products containing probiotics might allow to general improvement of its safer use in humans. The goal of the study was the evaluation of quality expressed by identity, colony forming unit (CFU) and antibiotic sensitivity ofprobiotics used in medicinal products available in Poland using the appropriate and validated procedures.
  
  
  METHODS
  The medicinal products containing L. rhamnosus, L. acidophilus, L. delbrueckii subsp. bulgaricus and B. animalis subsp. lactis, L. helveticus, and L. gasseri were tested for species identity performed with validated rep-PCR (BOXA 1R) method. The antimicrobial susceptibility of working seeds and strains isolated to 26 antibiotics were tested by disk diffusion and E-test methods using relevant references as recommended by EUCAST. The numbers of probiotic strains, expressed as cfu count per package, was done using plating plunge method.
  
  
  RESULTS
  All strains tested, except B. lactis, were found to be resistant to trimethoprim-sulphamethoxazole, nalidixic acid, metronidazole, and colistin. B. lactis was resistant to aminoglycosides. L. rhamnosus strains were found to be resistant to vancomycin, (MIC > 256 microg/ml) similarly to ATCC strains (L. rhamnosus GG 53103 and 244). The sensitivity to other antibiotics was strain specific. The rep-PCR method was found species and strain specific. All products tested fulfilled declared countent as measured by cfu count/package.
  
  
  CONCLUSIONS
  Quality of medicinal products containing probiotics was found undoubted and confirmed. The optimized strategy of quality monitoring of probiotics used in medicinal products can be used in dietary supplements and foodstuffs intended for particular nutritional uses.
authors.affiliation: Zakład Badania Surowic i Szczepionek, Narodowy Instytut Zdrowia Publicznego - Państwowy Zakład Higieny.
authors.forename: Aldona
authors.initials: A
authors.lastname: Wiatrzyk
authors.forename: Maciej
authors.initials: M
authors.lastname: Polak
authors.forename: Urszula
authors.initials: U
authors.lastname: Czajka
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Krysztopa-Grzybowska
authors.forename: Anna
authors.initials: A
authors.lastname: Lutyńska
mesh_terms: D000617:Aminoglycosides / Q000494:pharmacology; D001644:Bifidobacterium / Q000145:classification* / Q000187:drug effects*; D015169:Colony Count, Microbial; D024881:Drug Resistance, Bacterial; D005838:Genotype; D007778:Lactobacillus / Q000145:classification* / Q000187:drug effects*; D008826:Microbial Sensitivity Tests; D010641:Phenotype; D019936:Probiotics / Q000145:classification*; D013045:Species Specificity
chemical_list: D000617:Aminoglycosides