MicroBioLogics is in a unique position because it must address demands in guidelines and standards that are specific for different microbiology disciplines such as clinical, USP, food, water, and etc. The terms used in these guidelines and standards, although different, commonly mean exactly the same thing. Also, as guidelines and standards become accepted internationally, languages can become barriers to understanding.
To better serve our customers in different microbiology disciplines in the domestic and international market, we take this opportunity to offer a definition of terms and how they apply to MicroBioLogics products.
Download the Glossary of Terms and Definitions for a document of these terms.
Assayed Control Microorganism. The manufacturer determines the assay value. The manufacturer employs standardized methods and statistical sampling/analysis to calculate the mean assay value for an assayed control microorganism preparation.
Assayed Reference Microorganism. Multiple, independent laboratories determine the assay value through a collaborative effort. The independent laboratories employ self-imposed methods, statistical sampling/analysis to calculate the mean assay value for an assayed reference microorganism preparation.
Assay Value; The Mean. A statistical sampling plan and validated assay method is performed on pellets from each final product. All test results must fall within stated control limits as described in the Product Inserts. The test results are used to calculate the mean assay value for each lot of assayed microorganism preparation. The mean assay value is recorded on each Certificate of Assay.
Calibrator. A microbiology calibrator is an assayed and stable microorganism preparation. Independent laboratories that employ a similar test method establish the assay value. The established value is stated and other laboratories use the assay value as the target value for their test method(s). A common method to create a calibrator sample is to use the consensus assay value from similar test methods obtained during proficiency testing.
Certificate of Assay. This certificate is attached to each retail assayed control microorganism product and reference stock cultures with limited passages from reference culture status. The "peel-off" feature of the certificate facilitates a permanent record and provides documentation regarding the product quality control. Important quality control documentation includes the mean assay value and/or the number of passages the microorganism preparation is removed from reference culture status.
Certificate of Quality. This certificate is included in each shipment of retail reference stock cultures and can be found as the last page of the packing slip. This certificate is a permanent record and provides documentation regarding the product quality control.
Culture Authenticity. A reference culture is authentic. Indeed, the curators of culture type collections bear the responsibility to maintain and document the true characterization or authenticity of each microorganism placed on deposit. There appears to be an implicit understanding in guidelines or standards which implies that if preservation, processing, or repeated subcultures could lead to mutation or characterization aberrations, testing must be performed on the microorganism to provide documentation that mutations or aberrations have not occurred. Commercial manufacturers of reference stock cultures commonly employ the notation "Derived from . . ." or "Derivative of . . ." to identify the reference culture from which the reference stock culture has been produced. This designation also imposes on the commercial manufacturer when testing must be performed to provide documentation that reference stock culture mutations or aberrations have not occurred. MBL documentation records the tests and test results employed to authenticate the reference stock culture.
Culture Traceability. In the laboratory, records may be required to provide documentation or evidence that a working stock culture can be traced back to a reference stock culture and ultimately traced back to a reference culture. MBL’s retail microorganism preparations are traceable to a reference culture. Documentation records a chain-of-evidence that each final fabricated product can be traced to a reference culture.
Culture Passages or Subcultures. A passage or subculture is simply the transfer of established microorganism growth on media to fresh media. The subsequent growth on the fresh media constitutes a passage or subculture. Growing a reference culture or reference stock culture from its preserved status (E.g. frozen or lyophilized) is not a passage or subculture. The preserved microorganism is not in a stage of established growth until it is thawed or hydrated and grown for the first time. MBL’s retail microorganism preparations are limited to a predetermined number of passages from a reference culture. Documentation records the number of passages a final fabricated product is removed from reference culture status. Labeling and/or Product Inserts will list the number of passages.
Culture Preservation. Microbiology standards and guidelines are very explicit regarding the preservation and long-term storage of microorganisms. Two types of preservation are cited. Ultra-Freezing or storage of a microorganism suspension at minus 50°F (storage for one year) or -70°F (indefinite storage) IS a cited method. Lyophilization, freeze-drying or sublimation (solid phase of ice directly to the gas phase of vapor WITHOUT passing through the liquid phase of water) IS a cited method. Air-Drying IS NOT cited as an approved method for the long-term storage and preservation of microorganisms.
Culture Recovery; Control Limits for Reference Stock Cultures. The recovery of colony forming units (CFU) for pellet preparations of a retail reference stock culture must exceed 1,000 CFU per pellet. The exception is the recovery of 100 CFU per pellet for slow-growing fungi (E.g. Dermatophytes). An enumeration or colony count is performed on pellets from each lot of final product. Assurance is provided regarding minimum recovery and provides a continuing index for shelf life stability.
Culture Purity. A statistical sampling plan and test method for each lot of final product, with a zero tolerance specification for contamination, provides assurance that over 98.5% of each production lot is free from extraneous contaminating microorganisms.
Culture; Working QC Stock. A working QC stock culture is a microorganism preparation that is derived from a reference stock culture and in many microbiology disciplines is used as quality control challenge material on a regular, day-to-day basis. Guidelines and standards outline how working stock cultures must be processed and how often they can be subcultured.
Device Master Record (DMR). The DMR is the manufacturer’s document that lists all functions, activities, and criteria associated with production and distribution of each product as identified by the Catalog Number. Further, the outline and elements of FDA QSR are addressed in the DMR.
Device History Record (DHR). The DHR is the manufacturer’s permanent record that documents and provides assurance that each Lot Number of product meets DMR provisions.
FDA QSR. All MicroBioLogics products meet the provisions of the "Food and Drug Administration Quality System Regulation; 1996". Please contact the MicroBioLogics Compliance Officer at qsrcompl@mbl2000.com for more information.
Laboratory Calibration. This term has been used in Europe and other countries influenced by European standards and guidelines. A review of formal Inter-Laboratory Calibration Programs reveals similarity to formal External Proficiency Testing Programs employed in other areas of the world.
Phenotypic Profile. MBL provides assurance that the critical growth requirements, biochemical activity, selective and differential properties, serology characteristics, antimicrobial susceptibility, and key substrate reactivity, which are manifested in the reference culture, are manifested and unaltered in the final fabricated product. Documentation records phenotypic profiles upon receipt of the reference culture, is repeated at key steps during processing, and again as a final fabricated product. The phenotypic profile further documents the authenticity of the reference stock culture as a derivative of a reference culture.
Process Controls. Process controls are either qualitative (presence/absence) or quantitative (enumeration). These assayed control microorganism preparations are used on a regular basis (E.g. daily) to support and document that a test method is "in control". A common practice is to verify the manufacturer’s stated mean assay value AND establish the values or ranges of tolerance (E.g. +/- an established standard deviation) within which the laboratory must perform.
Proficiency Testing (External). This quality control function is offered by an independent third party and laboratories participate in a PT Program on a subscription basis. All the participating laboratories receive, process and test a similar challenge material for the presence or absence of a target microorganism(s) or enumerate a target microorganism(s). All the test results are analyzed and a value is established based on the consensus of the participating laboratories. The consensus is commonly established without regard for the specific test method(s) employed.
Proficiency Testing (Internal). This quality control function is most commonly a self-imposed function. A corporate laboratory will select a challenge material and request that other laboratories in the corporate net process and test the challenge material for the presence or absence of a target microorganism(s) or enumerate a target microorganism(s). All the test results are analyzed and a value is established based on the consensus of the participating laboratories. The consensus is commonly established and based on a without regard for the specific test method.
Product Specifications and Performance. Product specifications and performance is a simple statement that a product will produce specific and anticipated test results when stored, processed, used as directed, and used before the expiration date.
Product Warranty. This is an implicit guarantee by the manufacturer that a product will produce stated product specifications and performance when it is stored, processed, used as directed, and used before the expiration date.
Reference Culture. A reference culture is a microorganism preparation that is acquired from a culture type collection such as ATCC®, CIP or NCTC.
Reference Stock Culture. A reference stock culture is a microorganism preparation that is derived from a reference culture. Guidelines and standards outline how reference stock cultures must be processed and stored. In-house laboratory preparations and commercial preparations can meet reference stock culture criteria.
Validation. Validation is a process by which established scientific measurements, testing methods, sampling, and analysis are employed to document the anticipated, consistent, and reproducible performance of a device or product.
Verification. Verification is a process by which selected inspection, measurement, and testing is performed to determine that the objectives of the validation process have been met.
