Evaluation of the Effect of Single-Temperature Incubation on the Recovery and Behavior of Microbiota in the Context of Environmental Monitoring

Environmental monitoring is essential for the prevention and control of microbial contamination. Accurate and reproducible monitoring is critical, and standardized precise conditions of incubation in regulatory documents for environmental sampling are still lacking. This study investigated microbial recovery and growth dynamics under a controlled single-temperature incubation setting (25°C, 27.5°C and 30°C) across 83 microbial agents (49 bacteria, 24 molds and 10 yeast strains). We showed that at the temperature of 25°C, all microbial strains investigated were recovered. Elevated incubation temperatures did not alter the recovery of bacteria and yeast strains but affected the recovery and recovery rate of specific mold strains. In addition, time-to-result (TTR), defined as the time necessary for 90% colony recovery, varied with incubation temperatures and microbiota. It decreased with increasing temperature for all bacterial strains tested, while showing more complex patterns for molds. Altogether, our results contribute valuable insights into microbial ecology and highlight the complex interaction between temperature and microbial behavior. This study emphasizes the necessity for precise temperature regulation in microbial culture methodologies for accurate and reproducible environmental monitoring.