# Fermentation query

**URL:** <https://scientistsolutions.discourse.group/t/fermentation-query/794>\
**Category:** Microbiology\
**Created:** [January 18, 2025, 7:26am UTC](https://scientistsolutions.discourse.group/t/fermentation-query/794 "2025-01-18T07:26:53Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![harmandeep1618](https://yyz2.discourse-cdn.com/flex004/user_avatar/scientistsolutions.discourse.group/harmandeep1618/32/23_2.png) [@harmandeep1618](https://scientistsolutions.discourse.group/u/harmandeep1618)\
**Post date:** [January 18, 2025, 7:26am UTC](https://scientistsolutions.discourse.group/t/fermentation-query/794/1 "2025-01-18T07:26:53Z")

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hi! I am working with antibiotic fermentation producimg penicillin,erythromycin and lovastatin.In penicillin fermentation we face mould and yeast contamination at production state. please anybody is here to make useful contribution.

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**Author:** ![ARGERINE](https://avatars.discourse-cdn.com/v4/letter/a/8491ac/32.png) [@ARGERINE](https://scientistsolutions.discourse.group/u/ARGERINE)\
**Post date:** [April 16, 2025, 10:03pm UTC](https://scientistsolutions.discourse.group/t/fermentation-query/794/2 "2025-04-16T22:03:33Z")

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Harman

They may be:

- Present in **raw materials** (e.g., corn steep liquor, lactose)
- Introduced through **poor aseptic techniques**
- Surviving in **fermenter dead zones or piping**

To get rid of the issue, focus on

- **Sterilization:**
- Ensure all fermenters, pipes, and media are properly sterilized using SIP/CIP systems.
- **Additives:**
- Use safe antifungal agents (e.g., sodium benzoate) cautiously, to avoid harming penicillin-producing strains.
- **Environmental Monitoring:**
- Regularly check air, surfaces, and raw materials for contaminants using settle plates and air samplers.
- **Selective Media:**
- Use SDA or PDA plates to detect early fungal/yeast contamination.
- **Optimal Conditions:**
- Maintain correct pH (~6.0–6.5) and temperature (~25–27°C) to favor Penicillium over contaminants.
- **Inoculum Purity:**
- Use fresh, clean spores and aseptic transfer methods.
- **Signs to Watch For:**
- Sudden pH drop, sugar depletion, foam surge, or odd smells may indicate contamination.