Resistance to β-lactams in bacteria isolated from different types of Portuguese...

• Author(s): Amador, Paula ; Fernandes, Rúben ; Prudêncio, Cristina ; Brito, Luísa
• Date: 2009
• Persistent ID: http://hdl.handle.net/10400.22/1982
• Origin: Repositório Científico do Instituto Politécnico do Porto
• Subject(s): Ready-to-eat (RTE) food; Cheese, minimal inhibitory concentration (MIC); β-lactam-resistant enterobacteriaceae; Multiplex-PCR; BlaTEM gene
• Document Type: Article
• Language: English

Description

The purpose of this study was to investigate the presence of beta-lactam-resistant bacteria in six different types of Portuguese cheese. The numbers of ampicillin resistant (AMP(r)) bacteria varied from 4.7 x 10(2) to 1.5 x 10(7) CFU/g. Within 172 randomly selected beta-lactam-resistant bacteria, 44 resistant phenotypes were found and 31.4% were multidrug resistant. The majority (85%) of the isolates identified belonged to the Enterobacteriaceae family. The presence of the bla(TEM) gene was detected in 80.9% of the tested isolates. The results suggest that without thermal processing of the milk and good hygienic practices, cheese may act as a vehicle of transfer of beta-lactam-resistant bacteria to the gastrointestinal tract of consumers.