Chapter 6 Biotechnology test
The United States Pharmacopeia (USP) significantly changed the USP XXXI Microbial Limits Test. The updated USP test is now divided into two parts:
- USP Microbiological Examination of Non-Sterile Products: Microbial Enumeration Tests
- USP Microbiological Examination of Non-Sterile Products: Tests for Specified Microorganisms
The effective date is now May 1, 2009. Many of the changes are designed to harmonize with the European Pharmacopeia methods. A brief summary of the changes is listed below.
- USP Microbial Enumeration Tests includes changes in pass/fail criteria and includes longer incubation durations than in previous editions.
- The Preparatory Test is replaced by the Method Suitability for product inhibition. The growth promotion organisms and the methodology had been significantly updated to include more types of organisms and different growth medias.
- The tests for specified microorganisms are included in USP , the modifications change many microbiological medias utilized in testing for specific pathogens. Critical changes also are being made to incubation temperatures and duration.
- More organisms have been specified in the new USP chapter than in previous USP editions. Organisms such as Candida albicans, Clostridia species, and Bile-Tolerant Gram-Negative Bacteria may be required to be tested depending on specifications regarding product formulation.
Clients are advised to review the status of their non-sterile product testing in light of the upcoming changes to USP , Microbial Limits Testing. It is also recommending that these products be revalidated to conform to the new USP and Suitability Test. Clients must now specify which microorganisms are required to be absent. This requirement is based on the unique characteristics of the product based on formulation process, raw materials, etc.
Testing is performed as described in USP XXXI and an inoculum of not more than (NMT) 100 CFU.
Test organisms include:
- Aspergillus niger (ATCC #16404)
- Bacillus subtilis (ATCC #6633)
- Candida albicans (ATCC #10231)
- Escherichia coli (ATCC #8739)
- Pseudomonas aeruginosa (ATCC #9027)
- Salmonella typhimurium (ATCC #14028)
- Staphylococcus aureus (ATCC #6538)
- Clostridium sporogenes (ATCC #19404)
The new media and solutions recommended are:
- Cetrimide Agar (PSD)
- Enterobacteria Enrichment Broth Mossel (EEBM)
- MacConkey Agar (MAC)
- MacConkey Broth (MAC Broth)
- Mannitol Salt Agar (MSA)
- Phosphate Buffer (PB)
- Phosphate Buffer w/Tween 80
- Rappaport Vassiliadis Salmonella Enrichment Broth (RVSE)
- Sabouraud Dextrose Agar (SAB)
- Sabouraud Dextrose Broth (SAB Broth)
- Tryptic Soy Agar (TSA)
- Tryptic Soy Broth (TSB)
- Violet Red Bile Glucose Agar (VRBG).
- Xylose Lysine Deoxycholate Agar (XLD)
- Reinforced Medium for Clostridia (RM)
- Columbia Agar (CA)