Characterization of Antibiotic Resistant Coliform Bacteria and Resistance Genes Isolated from Samples of Smoothie Drinks and Raw Milk

Raw foodstuffs have been marked as a healthier alternative in the context of nutrient content and are becoming more popular with consumers. Thermally untreated foods may represent a microbiological risk connected with the possible presence of antimicrobial resistance. The aim of this study was to pr...

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Bibliographic Details
Main Authors: Monika Krahulcová, Klára Cverenkárová, Petra Olejníková, Barbora Micajová, Júlia Koreneková, Lucia Bírošová
Format: Article
Language:English
Published: MDPI AG 2022-05-01
Series:Foods
Subjects:
Online Access:https://www.mdpi.com/2304-8158/11/9/1324
Description
Summary:Raw foodstuffs have been marked as a healthier alternative in the context of nutrient content and are becoming more popular with consumers. Thermally untreated foods may represent a microbiological risk connected with the possible presence of antimicrobial resistance. The aim of this study was to prove that popular raw food beverages such as smoothies and raw milk may be a source of antibiotic-resistant coliform bacteria and resistant genes. The majority of antibiotic-resistant isolates (110) were identified as <i>Enterobacter</i> spp., <i>Escherichia coli</i>, and species of <i>Klebsiella</i> spp., predominantly β-lactam and chloramphenicol resistant. Multidrug resistance has been registered in one-third of resistants. Overproduction of efflux pumps was clarified in 8 different bacteria. The majority of resistant isolates were strong biofilm producers. Antibiotic resistance gene <i>bla</i><sub>OXA</sub> was detected in 25% of isolates, especially in <i>E. coli</i>. Resistance genes <i>bla</i><sub>TEM</sub> and <i>bla</i><sub>SHV</sub> were detected in 19% and 14%, respectively. This is the first study to point out that popular raw drinks such as smoothies or raw milk, besides their nutrient benefits, could represent a reservoir of antibiotic-resistant bacteria as well as antibiotic resistance genes. According to this, raw drinks could contribute to the dissemination of antibiotic resistance in the human gastrointestinal tract and environment.
ISSN:2304-8158