meets regulatory microbial limits.

4. Accountability

The QC Manager is accountable for ensuring that all microbial limit testing is performed according to this SOP. The Production Supervisor is responsible for ensuring that samples are collected from the appropriate batch and delivered for testing. The QA Manager ensures that the microbial testing results comply with GMP and regulatory standards.

5. Procedure

5.1 Pre-Test Preparation

1. Ensure that all necessary equipment and materials for microbial limit testing are available, including sterile sampling containers, microbiological media (e.g., Plate Count Agar, Sabouraud Dextrose Agar), incubators, and a clean testing environment.
2. Verify that all microbiological media are properly prepared and sterilized according to the manufacturer’s guidelines, and that the appropriate incubation temperatures are set (e.g., 30–35°C for bacteria and 20–25°C for molds and yeasts).
3. Review the batch record to identify the sampling points for microbial testing, which should be performed on finished products post-manufacturing, prior to packaging.

5.2 Sample Collection

1. Collect a representative sample from the final cream product batch according to the established sampling plan. Ensure that the sample is homogeneous and free from contamination.
2. Label the sample with the relevant information, including batch number, sample ID, and sampling date, to ensure traceability throughout the testing process.
3. If necessary, store the sample under appropriate conditions (e.g., refrigeration) until microbial testing can be performed to prevent any microbial growth before testing.

5.3 Microbial Limit Testing Procedure

1. In the QC laboratory, aseptically transfer the cream sample into sterile dilution buffer (e.g., phosphate-buffered saline) to ensure the sample is properly diluted for microbial testing.
2. Perform the microbial limit test using appropriate media for microbial enumeration:
   • Total Aerobic Microbial Count: Incubate the sample on Plate Count Agar (PCA) at 30–35°C for 48 hours to detect aerobic bacteria.
   • Yeast and Mold Count: Incubate the sample on Sabouraud Dextrose Agar (SDA) at 20–25°C for 5–7 days to detect yeasts and molds.
   • Pathogen Testing: Test for specific pathogens, such as Escherichia coli, Staphylococcus aureus, and Salmonella if required by regulatory guidelines.
3. For each sample, prepare triplicate plates to ensure accuracy and reproducibility of results. Perform all tests in triplicate to ensure reliable data.
4. Incubate the plates under specified conditions, and observe the growth of colonies after the required incubation period. Record the number of colonies (colony-forming units, CFUs) observed on each plate.

5.4 Interpretation of Results

1. Compare the observed microbial counts with the defined acceptance criteria for the cream product. The product should meet the microbial limits specified in regulatory guidelines, which may include limits on total aerobic microbial count, yeast and mold count, and the absence of specific pathogens.
2. If the microbial counts exceed the acceptable limits, mark the test as “Fail.” Investigate the root cause of the microbial contamination, which may include production, storage, or packaging issues. Consider corrective actions to address contamination sources.
3. If the microbial counts are within the acceptable limits, mark the test as “Pass” and proceed with the next stage of production, such as packaging and labeling.

5.5 Post-Test Activities

1. Record the test results, including batch number, sample ID, total aerobic count, yeast and mold count, and pathogen test results (if applicable), in the Microbial Limit Testing Log (Annexure-1).
2. Investigate any deviations or failed tests, perform root cause analysis, and implement corrective actions as necessary.
3. Submit all test results for review and approval by the QA team to ensure compliance with internal standards and regulatory requirements.

5.6 Documentation and Record-Keeping

1. Ensure that all microbial testing records are complete, accurate, and securely stored. This includes the Microbial Limit Testing Log (Annexure-1) and the Deviation Log (Annexure-2) for failed tests.
2. Retain all records for a minimum of two years or as required by regulatory guidelines.
3. Ensure that records are reviewed and approved by the Quality Assurance team to verify compliance with GMP standards and regulatory requirements.

6. Abbreviations

• GMP: Good Manufacturing Practices
• QC: Quality Control
• QA: Quality Assurance
• PPE: Personal Protective Equipment

7. Documents

1. Annexure-1: Microbial Limit Testing Log
2. Annexure-2: Deviation Log

8. References

• Good Manufacturing Practices (GMP) Guidelines – 21 CFR Part 211
• International Conference on Harmonisation (ICH) Q7 – Good Manufacturing Practice for Active Pharmaceutical Ingredients
• Pharmacopeial Monographs for Microbial Limit Testing

9. SOP Version

Version: 2.0

10. Approval Section

	Prepared By	Checked By	Approved By
Signature
Date
Name
Designation
Department

11. Annexures

Annexure-1: Microbial Limit Testing Log

Batch Number	Sample ID	Sampling Date	Total Aerobic Count (CFU/g)	Yeast & Mold Count (CFU/g)	Pathogen Test Results	Operator
12345	S-001	21/01/2026	150 CFU/g	Pass	No pathogens detected	John Doe

Annexure-2: Deviation Log

Deviation Date	Batch Number	Deviation Description	Corrective Action Taken	Operator
21/01/2026	12345	High aerobic count	Investigated production process; corrected contamination source	Jane Smith

Revision History:

Revision Date	Revision No.	Revision Details	Reason for Revision	Approved By
01/03/2024	1.0	Initial Version	New SOP Creation	QA Head
01/03/2025	2.0	Format Revision and Updates	Standardization of Document	QA Head