title: Detection of antibiotic resistance in probiotics of dietary supplements.
abstract: BACKGROUND
  Probiotics are live microorganisms that confer nutrition- and health-promoting benefits if consumed in adequate amounts. Concomitant with the demand for natural approaches to maintaining health is an increase in inclusion of probiotics in food and health products. Since probiotic bacteria act as reservoir for antibiotic resistant determinants, the transfer of these genes to pathogens sharing the same intestinal habitat is thus conceivable considering the fact that dietary supplements contain high amounts of often heterogeneous populations of probiotics. Such events can confer pathogens protection against commonly-used drugs. Despite numerous reports of antibiotic resistant probiotics in food and biological sources, the antibiogram of probiotics from dietary supplements remained elusive.
  
  
  RESULTS
  Here, we screened five commercially available dietary supplements for resistance towards antibiotics of different classes. Probiotics of all batches of products were resistant towards vancomycin while batch-dependent resistance towards streptomycin, aztreonam, gentamycin and/or ciprofloxacin antibiotics was detected for probiotics of brands Bi and Bn, Bg, and L. Isolates of brand Cn was also resistant towards gentamycin, streptomycin and ciprofloxacin antibiotics. Additionally, we also report a discrepancy between the enumerated viable bacteria amounts and the claims of the manufacturers.
  
  
  CONCLUSIONS
  This short report has highlighted the present of antibiotic resistance in probiotic bacteria from dietary supplements and therefore serves as a platform for further screenings and for in-depth characterization of the resistant determinants and the molecular machinery that confers the resistance.
authors.affiliation: Division of Biological and Environmental Sciences and Engineering, 4700 King Abdullah University of Science and Technology, Thuwal, 23955-6900, Saudi Arabia. aloysius.wong@kaust.edu.sa.
authors.forename: Aloysius
authors.initials: A
authors.lastname: Wong
authors.affiliation: UCSI University, No. 1, Jalan Menara Gading, UCSI Heights, Cheras, 56000, Kuala Lumpur, Malaysia.
authors.forename: Davey Yueh Saint
authors.initials: DY
authors.lastname: Ngu
authors.affiliation: UCSI University, No. 1, Jalan Menara Gading, UCSI Heights, Cheras, 56000, Kuala Lumpur, Malaysia.
authors.forename: Lydia Annabel
authors.initials: LA
authors.lastname: Dan
authors.affiliation: Division of Biological and Environmental Sciences and Engineering, 4700 King Abdullah University of Science and Technology, Thuwal, 23955-6900, Saudi Arabia. amanda.ooi@kaust.edu.sa.
authors.forename: Amanda
authors.initials: A
authors.lastname: Ooi
authors.affiliation: UCSI University, No. 1, Jalan Menara Gading, UCSI Heights, Cheras, 56000, Kuala Lumpur, Malaysia. reneelim@ucsiuniversity.edu.my.
authors.forename: Renee Lay Hong
authors.initials: RL
authors.lastname: Lim
mesh_terms: D001398:Aztreonam / Q000494:pharmacology; D001419:Bacteria / Q000187:drug effects*; D002939:Ciprofloxacin / Q000494:pharmacology; D019587:Dietary Supplements; D024881:Drug Resistance, Bacterial; D005516:Food Microbiology; D005839:Gentamicins / Q000494:pharmacology; D007778:Lactobacillus / Q000187:drug effects; D010865:Pilot Projects; D019936:Probiotics / Q000032:analysis*; D013307:Streptomycin / Q000494:pharmacology; D014640:Vancomycin / Q000494:pharmacology
chemical_list: D005839:Gentamicins; D002939:Ciprofloxacin; D014640:Vancomycin; D001398:Aztreonam; D013307:Streptomycin