Product Features

1.Maintains bacteria in a dormant state at ambient temperature.
2.Effectively preserves the stability of the microbiota composition and maintains bacterial viability, meeting the needs for subsequent experiments like microbiota isolation and culture.
3.Preserves fecal microbial samples for at least 7 days at ambient temperature.

I. Preservation Conditions

Storage temperature: 4°C (simulating conventional storage conditions) and room temperature (25°C, for extreme condition validation).

Testing time points: Day 0 (baseline), Day 1, Day 3, Day 5, Day 8.

II. Testing Methods

1.Bacterial Viability Testing

Quantitative culture: At each time point, take a 100μL sample of the preservation solution, perform gradient dilution, and inoculate onto selective media: ① Salmonella: SS Agar, Blood Agar; ② Pathogenic E. coli (generic Escherichia coli): Blood Agar.

Calculate CFU/mL and compare with the baseline (Day 0). The survival rate should be ≥50% (referencing CLSI M40-A2 standard).

2.Bacterial Proliferation Assessment

If the CFU/mL increases by more than 1 log (e.g., 10^4 → 10^5) within 8 days, it is judged as failed (proliferation unqualified).

3.Morphology and Biochemical Characteristics Verification

Pick colonies and identify the species using mass spectrometry to confirm they are the target bacteria.

4.Inhibitory Interference Testing

After inoculating the preservation solution, perform enrichment culture (e.g., broth for Salmonella), then transfer to Blood Agar to observe whether the enrichment effect is inhibited.

III. Evaluation Criteria (Qualification Requirements)

1.Survival Rate: The decrease in CFU/mL of the target bacteria within 8 days does not exceed 50% (compared to Day 0).

2.No Proliferation: The increase in CFU/mL does not exceed 1 log.

3.Identification Consistency: The biochemical characteristics of the strains at the final time point are consistent with the baseline.

4.No Cross-Contamination: No overgrowth of non-target bacteria on the selective media.

Bacterial Preservation Solution 8-Day Preservation Effect Validation Report (Test Results)

*Note: Bacterial count unit: *10⁴