Scientific Presentations & Whitepapers

Currently available growth-based rapid microbiological methods (RMM) provide either a quantitative cell count, estimation of viable cell concentration, information regarding the presence of a specific microorganism, or a microbial identification. However, the ability of these RMM technologies are limited in scope in that they cannot be used to perform all the required assays using a single technology platform.

A technology overview and validation case studies for the BioLumix System, a new RMM technology that is capable of simultaneously detecting microbial growth, providing an estimation of viable cell counts, and identifying the presence of specific microorganisms, using a novel and automated growth-based format is presented. The case studies demonstrate the ability of the technology to detect total aerobic microorganisms, total yeast and molds, and the presence of E. coli, Staphylococcus, Pseudomonas, Salmonella, as well as additional microorganisms.

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Coupons of various materials (stainless steel, aluminum, high density polyethylene, silicone rubber, and Plexiglas) were inoculated with microorganisms. The organisms were allowed to dry and thereafter the coupons were swabbed. Using total aerobic count, the coupons from each material were individually inoculated with the following bacteria: Bacillus spizizenii var subtilis ATCC 6633, Escherichia coli ATCC 8739, Pseudomonas aeruginosa ATCC 9027, or Staphylococcus aureus ATCC 6538. The yeast Candida albicans ATCC 10231, and the mold Aspergillus niger ATCC 16404 were used to inoculate each type of coupon for the yeast and mold count.

For the Enterobacterial count the coupons were inoculated with Escherichia coli ATCC 8739 and Citrobacter freundii ATCC 43864. The swabs were analyzed for total aerobic count, yeast and mold and Enterobacteriaceae, using the standard plate count method and the BioLumix system. The effects of both drying time and coupon material on the survival of the various microorganisms were evaluated. Aluminum was the most toxic surface. Both silicone rubber and Plexiglas were the least inhibitory. The highest numbers of organisms were recovered before complete drying followed by a decrease in viable numbers of each organism after a drying period of hours. The data showed a very high correlation between the standard plate count method and the BioLumix results. The BioLumix system is a rapid automated system that can simplify environmental monitoring and can replace the plate count method for the evaluation of environmental monitoring.

To meet the challenges of the new FDA regulations requires simpler, faster, and more streamlined microbiological tests. The BioLumix System enables users to perform the entire microbial testing operation in-house rather than sending their samples to outside laboratories for testing. Accordingly, the system allows companies to greatly reduce the amount of time and money required to have their samples tested by independent outside laboratories. Consequently, it enables earlier release of raw materials and finished products. The BioLumix System can help reduce quarantine time from 5 - 6 days, to approximately 35 - 48 hours for microbiology testing. In addition, the system is fully automated. The methodology developed is described.

The new FDA regulations regarding cGMP (current Good Manufacturing Practices) will require the Nutraceutical and Dietary Supplement Industries to streamline and develop faster and more effective microbiological assays. Currently, many manufacturers send their samples to outside testing laboratories. This is expensive and takes many days to obtain results. Internal laboratories are a better option but many manufacturers do not have the infrastructure or the personnel to internalize microbiological testing. The BioLumix System offers a fully automated microbiological system that can deliver much faster results, without the requirement of a full microbiological laboratory. The BioLumix System is comprised of an instrument with a capacity for testing 32 individual assay vials, software, and disposable vials.

Each instrument serves as an incubator. Up to 32 instruments can be connected to one computer. The software enables rapid, real-time results to be transferred to where they are needed most, without any operator involvement. The disposable vials are available for use in required microbiological assays including: total aerobic count (TAC), Yeast and Mold (YM), coliform (CM), E. coli (EC), Pseudomonas (PSE), Staphylococcus (SA), and Probiotics. All assay vials are provided with a ready to use sterile media and a certificate of analysis.

The BioLumix System enables users to perform the entire microbial testing operation in-house rather than sending their samples to outside laboratories for testing. The system simplifies microbiological testing with its ease of use and generates an automated certificate of analysis within 48 hours.

It is imperative that such a testing system is Robust & Rugged; obtaining the same results under a variety of normal test conditions while remaining unaffected by small variations in method parameters. The BioLumix System has proved to be just that. It demonstrated a high precision of test results obtained by analyzing the same microorganisms under a variety of different conditions.

Accordingly, the system allows companies to greatly reduce the amount of time and money required to have their samples tested by independent outside laboratories, while maintaining good accuracy, precision and robustness. Ready to use disposable vials are available for all the assays required (for example: Total Aerobic Count, Yeast and Molds, Coliform, Enterobacteriaceae, Escherichia coli, Staphylococcus aureus, and Salmonella.)

Introduction: The presence of most indicator organisms such as total aerobic count (TC), yeast and mold (YM), coliform and E. coli (EC) can be determined by the time consuming plate count methodology. In recent years the application of rapid automated methods, as alternatives to the plate count method, has become increasingly significant. BioLumix has developed a new optical system for rapid and automated detection of indicator microorganisms.

Purpose: To evaluate the new system and technology for the detection of TC, YM, coliform and EC, and show its applicability to environmental and UHT products testing.

Methods: The BioLumix system detects optical changes, due to microbial growth in liquid growth medium containing optically sensitive reagents (color or fluorescence). An embedded optical sensor for the detection of CO2, was used for TC and YM. The simultaneous detection of coliform and E. coli was achieved with a combination of color and fluorescent dyes. Stainless steel coupons inoculated with various types of bacteria, yeast and mold were swabbed. The inoculated swabs were tested for TC, YM or a combination of coliform/EC. UHT products were evaluated for the presence/absence of microorganisms using the BioLumix system.

Results: The surface of stainless steel coupons was inoculated with 83 different strains of bacteria, 14 molds and 12 yeasts. All detected by the CO2 sensor, while none of the un-inoculated samples were detected. The coliform/EC vial was capable of distinguishing between coliform and E. coli in environmental samples. There were 37 store-bought UHT products tested including: milk, half & half, shakes, and whipped cream. Additionally, 71 products were inoculated with low numbers of bacteria or yeast. The system clearly distinguished between clean and contaminated samples. Significance: The data suggests that the new method is useful for determining total aerobic count, yeast and mold as well as coliform and E. coli. More assays are currently under development.

Introduction: In cultured dairy products yeast and mold contamination is the most usual cause of spoilage. Such spoilage can be very costly for dairy manufacturers if prematurely spoiled products reach the marketplace. Therefore, yeast and mold levels need to fall within acceptable limits prior to the food leaving the factory. Consequently, reducing the test time from the traditional 5 days to 48 hours is very desirable to reduce product holding time. BioLumix has developed a new optical system for rapid and automated detection of yeast and molds in a number of food products.

Purpose: To evaluate the new BioLumix system and technology for the detection of yeast and molds in cultured dairy products. Evaluate the speed to results, its sensitivity and specificity.

Methods: The BioLumix system detects optical changes in an embedded optical sensor for the detection of CO2, located at the bottom of the test vial. Yeast and mold growth in the medium above the sensor results in CO2 production and changes in the sensor's color. The new ready to use yeast and mold vials were compared to the plate count methodology in its ability to detect yeast and molds, if present, in cultured dairy products.

Results: Various dairy products (yogurt, sour cream, cream cheese, cottage cheese, butter) clean, naturally contaminated or inoculated with different yeast or mold strains at levels of 10-50,000 cells/gr were tested. Over 100 combinations of yeast or mold and products were evaluated. All samples that contained yeast or mold detected by the CO2 sensor, while none of the un-inoculated samples detected. Therefore, the system clearly distinguished between clean and contaminated samples. Certain cultured dairy products required the addition of antibiotics to the vial to prevent drift in the curves due to starter culture activity. Most yeast detected within 24 hours, while molds required 48 hours to detect.

New U.S. Food and Drug Administration regulations for current good manufacturing practices (cGMP) enacted in June 2007 require more microbiological testing by nutraceutical and dietary supplement manufacturers. Producers will require faster and more cost-effective methods of testing to remain competitive while meeting the new regulations. The BioLumix system has been specifically designed to meet this challenge.

To reduce costs and testing times, the BioLumix system provides automated microbiological assays needed by the Nutraceuticals and Dietary Supplements industries. It is simple enough to be operated by non-microbiologists, cutting staffing costs, providing accurate data for raw materials, environmental samples, and finished products.

The BioLumix system uses ready-to-use vials with a CO2 sensor to detect bacteria, and yeast and molds. Color and fluorescent sensors are available to detect coliform and E. coli in a single vial, gram negative bacteria, Enterobacteriaceae, Pseudomonas spp. and Staphylococcus spp

To meet the challenges of the new FDA microbiological regulations requires simpler, faster, and more streamlined tests. These tests have to comply with the methodology described in the relevant USP chapters. The BioLumix system, as any other alternative testing system, has to be validated against the new chapters of USP (<2021>, <2022>, and <2023>). This poster describes the validation protocol used.

The validated BioLumix system allows companies to greatly reduce the amount of time and money required to have their samples tested by independent outside laboratories. This fully automated system delivers much faster results generating an automated certificate of analysis within 48 hours. Consequently, it enables earlier release of raw materials and finished products while adding profits to a company's bottom line.

The goal of this study was to compare the microbiological results of the automated BioLumix™-system with the results of quantitative and/or qualitative cultural methods according to DIN EN ISO. Naturally and artificially contaminated raw materials (egg powder, tapioca, frozen mushrooms, cocoa powder, and parsley) were analyzed with regard to the following test organisms: Total Viable Count (TVC), Yeast and Molds, osmotolerant yeast, Enterobacteriaceae, Escherichia coli and Salmonella. The BioLumix™-system detected these microorganisms within the defined specification levels. Analysis times were considerably reduced as compared with the DIN EN ISO methods.

During the past 20 years, the field of alternative and Rapid Microbiological Methods (RMMs) has been gaining momentum as an area of research and application across a number of technology sectors. Recent advances in rapid technologies have also encouraged the pharmaceutical and biopharmaceutical industries to validate and implement RMMs in place of their traditional microbiology methods within QC/QA laboratories and on the manufacturing floor.

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