USP 61

This test, also known as the Microbial Enumeration Test, determines the Total Aerobic Microbial Count (TAMC) and Total Yeast and Mold Count (TYMC) in non–sterile product samples.

The test is applicable to Cosmetics and Personal care products.

The test takes 5 to 6 days to complete.

We perform the test using the following microbial strains: Pseudomonas aeruginosa (ATCC 15442), Escherichia coli (ATCC 8739), Staphylococcus aureus (ATCC 6538P), Enterococcus hirae (ATCC 10541), Klebsiella pneumoniae (ATCC 4352), MRSA (ATCC 33591), Salmonella enterica ( ATCC 10708), Candida Albicans (MTCC 3017). Additional strains can be added on request.

The acceptance criteria is TAMC of 100-1000 cfu/ml and TYMC of 10-100 cfu/ml.

The primary methods include Membrane Filtration, Plate-Count Methods (Pour-Plate and Surface-Spread Methods), and the Most-Probable-Number (MPN) Method.

It ensures that the products meet established specifications for microbiological quality, safeguarding consumer health by preventing contamination.

The enumeration test is a quantitative method used to determine the number of viable microorganisms present in a sample. This test is crucial for ensuring the microbiological quality of non-sterile products, including pharmaceuticals, cosmetics, personal care products, and medical devices.

The Total Aerobic Microbial Count (TAMC) is a microbiological test used to quantify the number of viable aerobic bacteria present in a sample. This test is an essential part of quality control for non-sterile pharmaceutical products, cosmetics, personal care products, and other items that must adhere to specific microbiological safety standards.

The Microbial Limit Test (MLT) is a set of procedures used to assess the microbiological quality of non-sterile pharmaceutical products, cosmetics, and personal care items. It determines whether a product meets predefined microbiological criteria to ensure safety and quality for consumers.

Microbial count, also known as microbial enumeration, is a method used to determine the number of microorganisms (such as bacteria, yeasts, and molds) present in a sample. This measurement is crucial in various industries, including pharmaceuticals, food and beverages, cosmetics, and water quality, to ensure product safety, quality, and compliance with regulatory standards.

A bioburden test is a procedure used to determine the number and types of viable microorganisms present on a product or surface before it undergoes sterilization. This test is essential in various industries, including pharmaceuticals, medical devices, and food production, to ensure that products are safe and meet regulatory standards for microbial contamination.

The duration of bioburden testing depends on the incubation periods required for different microorganisms. Typically, the incubation period for bacterial bioburden testing is 3 to 5 days at 30 to 35°C. For fungal bioburden testing, the incubation period is 10 to 14 days at 20 to 25°C. These periods allow sufficient time for the microorganisms to grow and be counted accurately.

Samples are prepared by aseptic dilution in a sterile diluent to provide low-concentration levels for the plating. This is necessary to avoid errors in counting microbial colonies.

In case a product fails the test, an investigation is done to identify the source of contamination. The product can either be reformulated or rejected depending on the results obtained.

The test ensures that the microbial levels are within the acceptable limits in non-sterile products thus reducing the possible adverse health effects like infections and allergic reactions.

A controlled environment, working with sterile equipment, exercising good laboratory practices, and maintaining strict aseptic conditions can help reduce the possibility of contamination.

Sample ingredients that inhibit microbial growth, such as preservatives or poor sample preparation techniques, can give false positives for a microorganism’s presence.

USP  61 is for the determination of the presence of total viable aerobic bacteria and fungi. USP 62 deals with the detection of specific microbiological agents that may be pathogenic.

A recent update of the standard was recently approved by the Pharmacopeial Discussion Group (PDG). The update included changes in the procedure used to verify the suitability of the membrane filtration method.