Industrial fermentation practice: To maintain aseptic (sterile) conditions throughout a batch or fed-batch run, which measures are required?
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ASterilisation of the fermentor (vessel, lines, and medium)
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BSterile treatment of the inlet air supply (for example, HEPA or hydrophobic filters)
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CProperly designed aeration and agitation systems with sterile seals and fittings
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DAll of these
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ENone of these
Answer
Correct Answer: All of these
Explanation
Introduction / Context:Asepsis is critical in bioprocessing to prevent contamination that can ruin yields and product quality. Maintaining sterility is a system-level discipline, not a single step.
Given Data / Assumptions:
- A typical aerobic fermentor requires sterile vessel, sterile media, and sterile air.
- Mechanical assemblies (seals, impellers) must not introduce contaminants.
- Continuous operation demands asepsis for the entire duration.
Concept / Approach:Sterilisation-in-place (SIP) and clean-in-place (CIP) prepare the fermentor. Inlet gases are sterilised via filters. Agitation/aeration hardware must use sanitary design (mechanical seals, steam barriers) to keep the system closed and sterile under operating conditions.
Step-by-Step Solution:
Confirm the vessel and media are sterilised.Ensure the air supply is sterilised before entry.Operate agitation/aeration through sterile, sanitary fittings to maintain asepsis.Verification / Alternative check:GMP guidelines and standard bioprocess manuals prescribe all three elements as mandatory for aseptic fermentation.
Why Other Options Are Wrong:
Any single measure alone is insufficient; contamination can occur via unsterile air or mechanical ingress.“None” contradicts industrial practice.Common Pitfalls:Assuming air sparging is inherently sterile; it must pass through validated filters and sterile piping.
Final Answer:All of these.