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Study of psychrophilic and psychrotolerant micro-organisms isolated in cold rooms used for pharmaceutical processing
Aims:
To examine for psychrophilic or psychrotolerant micro-organisms in pharmaceutical cold rooms (in relation to numbers, incidents and species) and to determine, where such micro-organisms are present, whether standard microbiological environmental monitoring regimes require modification. This is presented as a case study.
Methods And Results:
Comparative environmental monitoring within different pharmaceutical facility cold rooms (using standard mesophilic and low temperature incubation). Data were collected over two periods, 5 years apart. The results indicated that psychrophilic micro-organisms were not present and that those micro-organisms deemed psychrotolerant, primarily pseudomonads, could be grown on standard media under mesophilic conditions.
Conclusions:
Psychrophilic micro-organisms were not detected and those considered to be psychrotolerant were only found in low numbers. Pyschrotolerant organisms were recovered under both low temperature incubation conditions and under standard conditions (between 20 and 35°C). Further evaluation may be required, using alternative agar, and microbiologists should regularly review the species recovered to note differences between different environments.
Significance And Impact Of The Study:
The study came about from requests made by US and UK regulators concerning the risk of any extremophiles present in pharmaceutical manufacturing facilities upon product safety. Regulators expressed concerns about whether standard, and accepted, environmental monitoring regimes were capable of detecting such micro-organisms. The data provide a benchmark to support pharmaceutical manufacturers in relation to their existing monitoring programmes or as a case study with which to undertake a similar study.
Insights
This study found no psychrophilic microorganisms in pharmaceutical cold rooms. Psychrotolerant organisms were present in low numbers and detectable using standard monitoring methods, suggesting current regimes are adequate.
Area of Science:
- Microbiology
- Pharmaceutical Manufacturing
- Environmental Monitoring
Background:
- Regulatory bodies in the US and UK raised concerns about extremophiles in pharmaceutical manufacturing.
- The potential impact of extremophiles on product safety necessitates evaluating current environmental monitoring practices.
Purpose of the Study:
- To investigate the presence and characteristics of psychrophilic or psychrotolerant microorganisms in pharmaceutical cold rooms.
- To assess if existing microbiological environmental monitoring regimes are sufficient for detecting these organisms.
Main Methods:
- Comparative environmental monitoring was conducted in pharmaceutical facility cold rooms.
- Standard mesophilic and low-temperature incubation methods were employed.
- Data were collected over two distinct periods, separated by five years.
Main Results:
- No psychrophilic microorganisms were detected in the pharmaceutical cold rooms.
- Psychrotolerant microorganisms, predominantly pseudomonads, were found in low numbers.
- These psychrotolerant organisms were successfully cultured under both standard mesophilic conditions (20-35°C) and low-temperature incubation.
Conclusions:
- Standard microbiological monitoring appears capable of detecting relevant psychrotolerant microorganisms.
- Current environmental monitoring regimes likely do not require modification based on these findings.
- Further research using alternative agar media and regular species review is recommended for comprehensive environmental surveillance.
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