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Improving and Comparing Probiotic Plate Count Methods by Analytical Procedure Lifecycle Management
M L Jane Weitzel1,2, Christina S Vegge3, Marco Pane4
1Expert Committee on Measurement and Data Quality, US Pharmacopeial Convention, Rockville, MD, United States.
Abstract:
Probiotics are live microorganisms that confer a health benefit to the host when administered in adequate amounts. This definition links probiotic efficacy to microbial viability. The current gold standard assay for probiotic potency is enumeration using classical microbiology plating-based procedures, yielding results in colony-forming units (CFU). One drawback to plating-based procedures is high variability due to intrinsic and extrinsic uncertainties. These uncertainties make comparison between analytical procedures challenging. In this article, we provide tools to reduce measurement uncertainty and strengthen the reliability of probiotic enumerations by using analytical procedure lifecycle management (APLM). APLM is a tool that uses a step-by-step process to define procedure performance based on the concept that the reportable value (final CFU result) must be fit for its intended use. Once the procedure performance is defined, the information gathered through APLM can be used to evaluate and compare procedures. Here, we discuss the theory behind applying APLM and give practical information about its application to CFU enumeration procedures for probiotics using a simulated example and data set. Data collected in a manufacturer's development laboratory is included to support application of the concept. Implementation of APLM can lead to reduced variability by identifying specific factors (e.g., the dilution step) with significant impact on the variability and providing insights to procedural modifications that lead to process improvement. Understanding and control of the analytical procedure is improved by using these tools. The probiotics industry can confidently apply the information and analytical results generated to make decisions about processes and formulation, including overage requirements. One benefit of this approach is that companies can reduce overage costs. More reliable procedures for viable cell count determinations will improve the quality evaluation of probiotic products, and hence manufacturing procedures, while ensuring that products deliver clinically demonstrated beneficial doses.
Insights
Analytical Procedure Lifecycle Management (APLM) reduces variability in probiotic enumeration. This ensures accurate colony-forming unit (CFU) counts, improving product quality and reducing costs.
Area of Science:
- Microbiology
- Analytical Chemistry
- Food Science
Background:
- Probiotics must contain adequate viable microorganisms for efficacy, with colony-forming units (CFU) as the standard measure.
- Classical plating methods for CFU enumeration exhibit high variability, complicating comparisons and quality control.
- Measurement uncertainties in current methods hinder reliable assessment of probiotic potency.
Purpose of the Study:
- To introduce Analytical Procedure Lifecycle Management (APLM) as a tool to reduce uncertainty in probiotic enumeration.
- To demonstrate how APLM enhances the reliability and comparability of CFU counting methods.
- To provide practical guidance for implementing APLM in the probiotics industry.
Main Methods:
- Application of APLM principles to define and manage the lifecycle of CFU enumeration procedures.
- Utilizing a step-by-step process to establish procedure performance based on fitness for intended use.
- Analysis of simulated and real-world data, including manufacturer development data, to illustrate APLM application.
Main Results:
- APLM implementation identified key factors contributing to variability, such as the dilution step.
- Procedural modifications guided by APLM led to process improvements and reduced variability.
- Enhanced understanding and control over analytical procedures for CFU enumeration were achieved.
Conclusions:
- APLM provides a robust framework for improving the reliability of probiotic viable cell count determinations.
- Implementing APLM enables confident decision-making in probiotic formulation and process control, including overage requirements.
- This approach leads to cost savings through reduced overage and ensures products deliver the intended beneficial doses.
