Influence of different medium components on the in vitro activity of the growth-promoting antibiotic flavomycin against enterococci
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Published on: November 16, 2016
P Butaye1, L A Devriese, F Haesebrouck
1Laboratory of Veterinary Bacteriology and Mycology, Department of Pathology, Bacteriology and Poultry Diseases, Faculty of Veterinary Medicine, University of Ghent, Merelbeke, Belgium. pbutaye@allserv.rug.ac.be
Abstract:
The growth-promoting antibiotic flavomycin (also called bambermycin, flavophospholipol and moenomycin) has a complex spectrum of activity against enterococci, with some species being naturally resistant and others susceptible. In this study, proteins added to Mueller-Hinton II medium had a strong deleterious effect on the activity of flavomycin, glucose had no effect and starch decreased the activity of flavomycin. The fatty substances Tween 80 and tributyrin increased the activity of flavomycin for several enterococcal species. Slight differences in the composition of the susceptibility test medium affected the MIC results obtained, indicating that strict standardization of the test medium is necessary.
Insights
Flavomycin
Area of Science:
- Antimicrobial resistance
- Bacterial susceptibility testing
Background:
- Flavomycin (bambermycin) is a growth-promoting antibiotic with variable activity against enterococci.
- Enterococcal species exhibit diverse susceptibility profiles to flavomycin.
- The efficacy of flavomycin can be influenced by medium composition.
Purpose of the Study:
- To investigate the impact of various medium supplements on flavomycin activity against enterococci.
- To determine the influence of medium composition on minimum inhibitory concentration (MIC) values for flavomycin.
Main Methods:
- Testing flavomycin activity in Mueller-Hinton II medium supplemented with proteins, glucose, starch, Tween 80, and tributyrin.
- Evaluating the effect of these supplements on the minimum inhibitory concentration (MIC) against enterococcal species.
Main Results:
- Proteins significantly reduced flavomycin activity.
- Starch decreased flavomycin activity, while glucose had no discernible effect.
- Fatty substances (Tween 80, tributyrin) enhanced flavomycin activity for certain enterococci.
- Minor variations in medium composition led to altered MIC results.
Conclusions:
- Medium composition critically affects flavomycin's antimicrobial activity and MIC values.
- Strict standardization of susceptibility testing media is essential for reliable flavomycin efficacy assessment.
- Understanding medium-specific effects is crucial for optimizing flavomycin use in enterococcal infections.
