Antimicrobial susceptibility testing of lactic acid bacteria and bifidobacteria by broth microdilution method and Etest

Autor: Sophie Legrain-Raspaud, Akira Kushiro, Christian Chervaux, Audrey Perony, Stéphanie Cools-Portier, Masaharu Onoue, David Obis, Ariane van de Moer
Rok vydání: 2008
Předmět:
Zdroj: International journal of food microbiology. 132(1)
ISSN: 1879-3460
Popis: We applied two methods of broth microdilution and Etest for measuring minimal inhibition concentration (MIC) of lactic acid bacteria and bifidobacteria for 15 antimicrobial agents to compare the feasibility, reproducibility, and equivalence of the two methods. Both methods were originally described by the European projects PROSAFE and ACE-ART. In 84% combinations of strains and antimicrobial agents MIC differences between the two methods were within one Log(2) dilution. In the case of rifampicin the difference between the two methods was more than ten-fold. We further determined MICs of 70 strains (14 strains of Lactobacillus delbrueckii ssp. bulgaricus, 16 strains of Lactococcus lactis, 30 strains of Streptococcus thermophilus, and 10 strains of Bifidobacterium longum) by the broth microdilution method. In most cases, MIC distributions were uni-modal and within 5 Log(2) dilutions except for the MIC distribution of L. lactis to the aminoglycoside group which was broader. These data are a good basis for improving knowledge of antimicrobial susceptibility of lactic acid bacteria and bifidobacteria, and can be used to revise tentative epidemiological cut-off values.
Databáze: OpenAIRE