Visit Neogen at IAFP — Booth #544

By Joe Heinzelmann

The International Association of Food Protection’s (IAPF) annual meeting is taking place this year from Saturday, July 25th — Tuesday, July 28th. The event features leaders from the food safety industry and hosts a wide variety of presentations, workshops and professional development groups.

Neogen will be in attendance at booth #544, showcasing a number of new products including Reveal 3D for Multi Treenut, innovations for ANSR—a molecular pathogen detection platform—and AccuPoint Advance, the latest innovation in hygiene monitoring, By visiting Neogen’s booth you’ll be able to see how the new design of our AccuPoint Advance sampler allows for better recovery, and more accurate results.

Also, if you haven’t picked up a copy of Neogen’s Food Allergen Validation and Verification Handbook, please stop by our booth to do so. This handbook provides guidelines, best practices and sound strategies for validation of allergen control plans, and the routine verification.

In addition, IAFP offers a wide range of educational opportunities. Some of the presentations covered in the meeting can be seen in the schedule overview and include recurring themes in genomics and process control. For example, the new Food Safety Modernization Act and the focus on preventive controls will be covered along with genomic sessions that cover identification methods, whole genome sequencing, next generation sequencing and more.

Examples of these talks include:

We look forward to seeing you at IAFP. If you will be at the event, please register for a time to speak with us here. See you in Portland!

For more information on the conference, click here.

Preservative efficacy testing: considerations and areas for savings

By Joseph Heinzelmann

Often one of the first questions we receive about the BioLumix system is “how much does it cost?” While this blog post won’t be able to cover specifics on the costs of the BioLumix system or the individual tests, it will outline some of the considerations and areas for savings as it relates to preservative efficacy testing according to the United States Pharmacopeia <51>.  In our example analysis, we are able to reduce the cost of doing PET by nearly 40%.

USP <51> helps show the effectiveness of a preservative, or a preservative system. This testing is done according to the procedures outlined in USP Chapter <51> Antimicrobial Effectiveness Testing. This chapter describes in detail which organisms to use, the appropriate inoculum based on a product, and the necessary log reductions that the preservative system needs to achieve.

Before getting started on a comparison of protocols, we have to make sure a suitability study has been performed. The following link describes how suitability can be performed: The experts at Neogen can help you with your suitability testing questions.

Before a side-by-side comparison is done, a validation is required of any alternative method. Using the protocol outlines in USP chapter <1223> Validation of Alternative Microbiological Methods we can see that the BioLumix system meets the following requirements: Specificity, Limit of detection, precision and repeatability, robustness ruggedness, false negative rate, and false positive rate. A more in-depth discussion around USP validations and Neogen’s Validation book can be found here:

An overview of USP <51> can be found here: The two methods can be broken down into two approaches; materials and labor. Comparing the materials is straight forward. Reviewing the protocol shows that each time point requires an analysis of 3 bacteria, 1 yeast and 1 mold. Each organism requires a neutralization, and multiple dilutions when using traditional microbiology. Each organism also requires a total of 5 plates! Each plate requires a dilution blank, as well as a pipette tip.

There are several points of parity between the USP <51> traditional plate count methodology and the BioLumix system. First, the BioLumix system also requires 3 bacteria, 1 yeast, and 1 mold to comply with USP <51>. Each method will also test the preservative system at multiple time points over the course of 28 days. However, the BioLumix system is able to provide a microbiological count without 5 plates, without multiple dilution blanks, and without multiple pipette tips. The picture below helps illustrate how a nearly 40% reduction is achieved with Neogen’s BioLumix system methodology.

The second comparison is to determine the amount of labor required to run a USP <51> protocol with traditional methods. With the automation of the BioLumix system eliminates plate reading. The vials in the BioLumix system are automatically read, and the result is recorded in the database. Report writing is simplified with the Certificate of Analysis generated automatically. Time study estimates performed by Neogen estimate the labor reduction using BioLumix for PET is greater than 60%!

The BioLumix system is great for additional quality testing according to USP chapters 61 and 62. The advantages of BioLumix for this application has been covered in a recent blog post:

Learn more by asking our experts for a cost breakdown, suitability analysis or additional information by contacting the author or our microbiology experts.


Join Neogen at ASM2015

Neogen invites you to visit them at booth #674 at the American Society of Microbiology (ASM) General Meeting coming up next month from May 30 — June 2.

Held at the Ernest North Morial Convention Center in New Orleans, ASM2015 is
one of the largest microbiology conferences and Neogen will be exhibiting their leading microbiological testing products.

Neogen has a suite of microbiological testing products, including dehydrated culture media – Acumedia.  Neogen also has pathogen detection methodologies for food matrices. These tests are often used in conjunction with Neogen’s line of Acumedia product. More information on Neogen’s Food Safety division and foodborne pathogen detection systems can be found here.

In addition to the traditional and pathogen detection methodologies, Noegen also has the BioLumix system. The BioLumix system helps customers rapidly test finished goods, raw materials, or in-process commodities for bacteria, yeasts and molds, and other objectionable organisms. One of the key features of the BioLumix system is the 48 hour certificate of analysis. Dietary supplement and nutraceutical companies are able to maintain compliance with certain aspects of 21 CFR part 111 using the BioLumix system. Also, the validation book helps our customers easily survive audits and come as a package deal with the BioLumix system from Neogen.

To help solidify your knowledge and keep you up-to-date in the evolving world of microbiology, there are also several educational sessions at ASM2015. These included everything from overviews on pathogenic organisms, to detection and characterization developments. Additional interesting topics include transmission of pathogens, evolution of microbes, and even natural food trends as they relate to microbiology.

Whether you are a manufacture, a researcher or a student, Neogen would love for you to stop by their booth to talk more about microbiology and discuss the food safety solutions we have available. ASM2015 is shaping up to be another great conference and Neogen is looking forward to hearing what exciting things you’re learning while you’re there.

Reducing the cost of preservative efficacy testing

By Joe Heinzelmann

The implementation of cGMP for all manufacturers (large and small) of dietary supplements andNutraceutical productsmeans that all manufacturers must test their products for microbiology quality assurance and generate a Certificate of Analysis for each batch. Products must be tested in accordance with the methods described in USP <2021> and <2022>.  This includes testing for Total Aerobic Microbial Count, Total Combined Yeast and Mold, Bile-Tolerant-Gram-Negative bacteria, and objectionable organisms (absent in 10 grams of organisms such as SalmonellaE. coli, and sometimes S. aureus). To do these tests companies either send product samples to contract laboratories for microbiological testing or test them internally.

Internal testing of products for microbiology gives the manufacturer much more control over the operation, but some manufacturers are hesitant to bring the microbiology testing in-house for fear of the complexity of testing or the need for trained microbiologist(s).  Also daunting is the need for a full validation package which is required for any method that deviates from the USP methodology. Here’s the good news – BioLumix offers a solution that gives faster time to results, quicker product release, cost effective operation, and strengthens key profit drivers.   This is all achieved on a single platform that is easy to use, validated to USP requirements, and doesn’t require additional skilled personnel.

At BioLumix, we don’t just offer you a simplified, rapid, automated microbiology system… we provide the Complete BioLumix Experience!

What is the Complete BioLumix Experience?  It’s having, from initial contact to the completion of the installation and beyond, our commitment to providing unparalleled support and total customer satisfaction.

In 2006, Ruth & Gideon Eden established BioLumix, Inc.  Today, because of their extensive backgrounds in science and technology combined with customer-oriented sales and support staff, we have raised the simplification, automation and speed of microbiology testing to a new level.

  • Needs Assessment - Whether you contact us direct or through our website you can count on our sales team to respond quickly.  The focus is on your needs and goals.  Our BioLumix Technology Presentation provides an in depth look into how and why our system will work for you.  In addition, we can quickly and easily show you the value and the ROI the system will bring to your company.
  • Expertise – Knowing how the BioLumix system will work with your samples gives you peace of mind.  That’s why we test samples – YOUR samples – for you at our laboratory in Ann Arbor, MI.  We do this for you at no cost and at no obligation!  Once completed, expect a comprehensive report from one of our expert microbiologists. That same microbiologist spends two and a half days on-site for training and installation of the system.
  • Validation – If you are concerned about validation, here is more good news.  We provide complete SOPs along with a customized Validation book which includes Installation Qualification (IQ), Operations Qualification (OQ) and Performance Qualification (PQ).
  • Simplicity and Ease-of-Use-  The easy to master BioLumix system offers a new level of productivity.  Sample preparation takes less than 2 minutes; just add the sample to the diluent and mix.  Pipette the appropriate amount into the vial and place it into the instrument and record the sample and assay information into the computer.  The rest is totally automated.  The Certificates of Analysis will automatically be generated in as little as 24-48 hours!
  • Support – Our jobs center on satisfying our customers and providing unparalleled support.  At BioLumix you receive 24/7 support plus a microbiologist dedicated to service you and answer your questions.  What happens if you encounter a problem? Troubleshooting can be done via the internet and in most cases problems are resolved.   If needed we provide a loaner instrument while your instrument is being fixed to minimize downtime.  Our website provides instant access to information and resources about our technology, instruments, assays, and more.  It’s also mobile-enabled to format to your handheld devices.  Links to social media, white papers, blogs, videos, and other informative contact information puts everything you need at your fingertips.
  • Continuous Product Improvement – At BioLumix we have an ongoing commitment to evolving and adding to our platform.   One way this is achieved is through our partnership with our customers.  Customer feedback, along with a desire to increase the breadth and depth of our offerings, helps us to make improvements to our media and our assays.  We have recently introduced two new assays – Listeria and Bacillus cereus.

With a simplified method such as the BioLumix System we can provide a simple cost effective method to test products for microbiology.

Join Neogen at Ingredient Marketplace 2015

By Joe Heinzelmann

Join Neogen at booth #528 from April 7th – 9th for Ingredient Marketplace 2015 at the Orlando World Center Marriott.

Ingredient Marketplace brings together experts in the community of nutrition,
health, food and beauty products and provides opportunities for networking, purchasing and business development. Additional insights from educational programs include global insights, and categorical trends.

Neogen is a world leader in food safety, and excited to showcase new solutions to facilitate cGMPs, quality assurance programs, and verification systems at Ingredient Marketplace. Neogen will be presenting new, key products that have been validated specifically for nutritional, health food, beauty and other related products and include the BioLumix System, allergen control tests and plans, as well as hygiene monitoring equipment.

The BioLumix Rapid Microbiology System saves time, reduces staff involvement, and leads to faster product release. The validated BioLumix system also allows for easy compliance with cGMP, streamlining your microbiological testing and once again saving you time, labor and money. BioLumix delivers shorter sample preparation, automated real-time communication, fast product release and early warning of contamination. The system is also paperless and efficient, saving on disposables, time and space, while eliminating product interference, and delivering accurate results.

The BioLumix system is also fully automated, validated against USP
and supports 21 CFR Part 11 Compliant. The system delivers complete microbiology testing results within 24-48 hours, allowing for faster product release time and shorter sample prep time.

In addition, Neogen’s allergen testing solutions help companies put together best practices for allergen control. Neogen’s industry supported Supplier verification document starts with raw materials. Using testing and best practices, companies can have confidence that ingredients, sanitation teams and their products all comply with allergen label claims.

Please also visit Neogen at booth #528 to hear more about AccuPoint Advanced, Neogen’s newest and most complete hygiene monitoring system and to see a demonstration as to why the AccuPoint Advance is the right tool for the job.

Accelerating the detection of yeast and mold in yogurt

By Jennifer Johnson

What was once an obscure foreign dairy product, Greek yogurt has exploded into a billion dollar business, and it is still growing!  Greek yogurt sales are 50% higher than at this time last year and represent more than one-third of all yogurt sold in the U.S. By comparison, in 2007 Greek yogurt accounted for only 1% of the total yogurt market.

As with regular yogurt, Greek yogurt is made from fermented milk that is soured and thickened by adding specific lactic acid-producing cultures. However, Greek yogurt is strained more times than traditional yogurt to remove more whey. As a result, Greek yogurt is thicker and has more protein than regular yogurt. The basic cultures or probiotics used to make yogurt are Lactobacillus bulgaricus and Streptococcus thermophilus and many additional probiotic organisms are often added which include Lactobacillus acidophilus, Lactobacillus casei, and Bifidobacterium species, all of which may help to maintain the balance of bacteria needed to boost the immune system and promote a healthy digestive tract. According to the Obesity Action Coalition, yogurt is the number 1 natural source of probiotics eaten by Americans. The live microorganisms in Greek yogurt can help improve your digestive system, help your body absorb nutrients, and improve your health. Greek yogurt may also help ease gastrointestinal conditions like constipation, inflammatory bowel disease, lactose intolerance, and diarrhea.

It is this overabundance of helpful bacteria that can interfere with the detection of yeast and molds in Greek yogurt.

Yeast and Mold Testing in Yogurt

Undesirable microorganisms constitute the primary hazard to safety, quality, and wholesomeness of milk and dairy foods. Yogurt is susceptible to microbial contamination, especially by fungi which grow and reproduce in acidic environments containing oxygen.  In a study by Montagna (1998), a variety of differently manufactured yogurts from a variety of manufactures tested positive for fungi, of which 75% of the 7.2% positives were yeasts and 25% were molds with counts between 200 and >106 cfu/ml. Yogurts contaminated by fungi can have modified organoleptic characteristics. The most common molds found were Aspergillus and Penicillium and the most common yeast belonged to Candida, Cryptococcus, Rhodotorula species.

Traditional methods are slow, tedious, labor intensive, and often not suitable for assessing the quality and shelf-life of perishable dairy products. The emphasis on the programs based on HACCP (Hazard Analysis and Critical Control Points) for total quality management in the dairy industry and increased demand for microbiological surveillance of products, process, and environment, have led to increased interest in rapid methods and automation in microbiology. In the past few years rapid automated methods such as BioLumix and Soleris have been adopted to speed up time to results and automate and simplify the microbiologist tasks.

The BioLumix technology can make the microbiological testing simpler, faster, and automated, saving time, labor and money. 

The BioLumix test method for detection of yeast & molds involves a direct addition of the sample into ready to use vials and automated monitoring of the samples in the instrument. This simple method saves labor and disposables.  The yeast & mold assay is completed in 48 hours as compared to the 5 days required for the standard assay.

The ready–to-use vial comes with media that is pre-adjusted for pH, such that after the addition of the sample the appropriate pH for the growth of the microorganisms is attained. BioLumix has developed such a media that is custom made with a higher pH to accommodate the low pH of yogurt while still maintaining the capability to test as much as 1.0 gram of product directly in the vials. The addition of the supplement to the vial results in the elimination of background growth from lactic bacteria resulting in flat curves.

The initial work with yogurts containing high levels of probiotics showed that the probiotics caused false detection in the instrument due to the CO2 production by the Probiotic bacteria.  As shown in the picture below, the addition of a supplement containing inhibitors to prevented the growth of the probiotics in the vials and resulted in a clear detection of fungi, when present, and a clean flat curve when organisms are not present. 

This newly developed assay has a high sensitivity, being able to detect a few yeast or molds in a gram of sample, is easy to perform (less than one minute hands on time), and result in quick time to results. Many different flavors of various brands of yogurt were tested and none created a false positive result.  Store bought contaminated yogurt detected in the system as did all the samples inoculated with low levels of yeast or mold.

The BioLumix System is designed to accelerate product release with a simplified, automated approach. The system yields fast, accurate, real-time results while reducing costs and eliminates the time required for the assays to be completed.  The system offers real-time results of contaminated samples saving hours, possibly days.

BioLumix will streamline and simplify the microbiological procedures, save labor and create a paperless laboratory, while generating results that correlate well with plate count methodology.

If you are interested in participating a field trial with Neogen’s new test, please contact


M.T. Montagna, R. Erroi, S. Sanapo, G. Caggiano, F. Bagordo, A. De Donno, Food products and fungal contamination. Note I. Preliminary investigation in commercial yoghurt. Journal of Preventative Medicine and Hygiene 39: 68-70. 1998

USP Sample Preparation Comparison

By Jason Kircos

Many companies use in house laboratories and perform using USP methodology. In these cases, when it comes to preparing their own media and reagents, the lab needs to pay special attention to USP because the quality of the results depends on the quality of the culture media prepared. This includes accurate weighing of dehydrated components, the use of high quality (USP purified) water, completely dissolving the dehydrated media or individual ingredients, and the need to control the heating of the media to avoid damaging heat-labile components of the media. The quality control of each batch of the media is a critical concern. However, a major issue with microbiological testing is the hidden costs in labor and inventory hold time.

The BioLumix system simplifies the testing due to the pre-made vials that do not require a technician to run quality control on the vial.

Sample preparation for the USP to BioLumix is very similar, so the transition for most laboratories is very simple. The benefit that is gained is the time it takes to get results and the ease of processing samples.

One example for sample processing is Yeast and Mold, which shows the advantage of the BioLumix system. Both the USP and BioLumix sample preparations start with a 10 gram sample into 90ml of either Butterfields Buffer or Fluid Soybean-Casein Digest Medium (TSB). The sample is then tested for pH to make sure it is the optimal range (6.0-8.0). From this point the BioLumix system shows how much easier and efficient an automated system is over the traditional methodology.

For the BioLumix system, the sample is then added to the vial, the information is added to the system, the sample starts running and 48 hours later, the data is archived and completed.

Now, compare that to the traditional USP methodology. First is the need to melt the agar used to pour the plates, and the time it takes to allow the media to temper down to an appropriate temperature that does not damage any possible organisms in the product. Then you must take the sample and pipette it onto the plate, and then pour the tempered media on the plate. Next, comes swirling the media and sample to evenly distribute it throughout the plate. Finally, then use must allow it to solidify and then place in the incubator for 5-7 days. Once the incubation is complete, read the plate and record the results.

The BioLumix system gives the result in 48 hours and automatically tells the customer if it is above or below the specification level. While the traditional USP methodology needs to wait 5-7 days before results are complete.

Many other assays that use the BioLumix system reduce the time to get results much quicker than USP. For example, total aerobic count which instead of 2-3 days using traditional USP methodology, is less than 24 hours on the BioLumix system.  E. coli testing takes three days using USP methodology but only two days using the BioLumix system.

The BioLumix System is a system that fits the needs of the supplement industry in terms of speed, working with all product matrices, and automatically documenting the results in real-time, thereby reducing the labor requirement for microbiological testing.

The BioLumix system was extensively validated for dietary products and compared to the methodology described in USP <2021> and <2022>.  The validation methodology followed USP <1223> “Validation of Alternative Microbiological Methods”.  This included performance criteria such as: side-by-side comparison to the USP methodology, accuracy and precision, specificity, limits of detection and quantification, along with ruggedness and robustness, reproducibility of the results, false positivity rate and false negative rate.

For more information, click here.

Join Neogen at Engredea 2015

By James Topper

Join Neogen at booth #175 on March 6– 8, 2015 for Engredea 2015 at the Anaheim Convention Center.

Engredea brings together a community of leading suppliers and manufacturers of new
ingredients, packaging, technologies, equipment, and services in the global nutrition industry. Engredea, co-located with Natural Products Expo West, is the only trade show that brings together the full food chain of supply to shelf.

Neogen, a world leader in food safety, is excited to showcase new solutions to facilitate cGMPs, quality assurance programs and verification systems at Engredea. Neogen will be presenting new products that have been validated specifically for natural products, dietary supplements, and other nutritional products.

These include:

  • The BioLumix System
  • Allergen control tests and plans
  • Hygiene monitoring equipment

The BioLumix Rapid Microbiology System delivers significant reduction in time to results, reduced staff involvement, and faster product release. BioLumix can save multiple days versus current testing methods and dramatically impact key profit drivers. The validated BioLumix system allows for easy compliance with cGMP. BioLumix will streamline your microbiological testing saving significant time labor and money. BioLumix delivers shorter sample preparation, automated real-time communication, fast product release and early warning of contamination. It is paperless and efficient, saving on disposables, time and space. The system eliminates product interference, delivering accurate results.

With BioLumix Rapid, Automated Microbiology you can view microbiology product testing from a position of company strength and competitive advantage! Streamline your microbiological testing, reduce cost, increase efficiency and show rapid return on investment. The BioLumix system is FDA compliant, fully automated, validated against USP methodology and 21 CFR Part 11 Compliant. The system delivers complete microbiology testing results within 24-48 hours, allowing for faster product release time, shorter sample prep time – saving time, money and other resources.

Neogen’s allergen testing solutions help companies put together best practices for allergen control Neogen’s industry supported Supplier verification document starts with raw materials. Using testing and best practices, companies can have confidence that ingredients, sanitation teams, and their products all comply with allergen label claims.

AccuPoint Advanced is Neogen’s the newest hygiene monitoring system. It gives users the most complete system, from accurately capturing samples, to generating useful information to drive improvements. Visit Neogen’s booth #125 to hear more about the new system, and see a demonstration to see why the AccuPoint Advance is the right tool for the job.

Soleris and BioLumix – when to use which system

By Joseph Heinzelmann

As the need for rapid microbiological testing in various industries continues to grow, Neogen’s recent acquisition of BioLumix helps provide new resources to an already successful rapid microbiological testing product. Specifically in the nutraceutical, dietary supplement, cosmetic and pharmaceutical markets, the BioLumix system serves customers with a system supported by validation datasets, ready to use microbial tests, and Neogen’s excellent customer service. In fact, the value of the system from the perspective of some of our customer’s can be found in their testimonials and feedback. Along with great customer service, some of the key aspects that customers are able to take advantage of include 48-hour certificate of analysis and ready to use assays.

Upon reviewing both the BioLumix system and Soleris, it is apparent that both of these systems offer advantages over other methods and products. These include:

  • Expedited results: most results in 12-18 hours; Yeast and mold assay in 48 hours
  • Automation and connectivity allows faster product release
  • Streamlined testing increases laboratory efficiencies
  • Paperless laboratory: centralized test data automatically stored and protected
  • Ready to use test vials
  • Excellent customer support

The differences lie in the application and validation information supporting both systems. For example, the BioLumix system has submitted a DMF to help aid companies on technical and regulatory information on approvals for prescription drugs. The BioLumix system has an established protocol for preservative efficacy testing, adhering to USP Chapter <51>. Neogen also has the capability to provide services on the BioLumix system, such as suitability testing, USP Chapter <61>.  The BioLumix system comes with uniquely designed validation books for nutraceutical and dietary supplements, cosmetics and toiletry, and for over the counter medication.

Similarly, the Soleris system has been for various food matrices. For
example Soleris has been validated for use in aseptically packed UHT products, dressings and sauces, and many other matrices as supported by the AOAC approvals. Because of the focus over the last few years of Soleris in food matrices, Neogen has developed various tests and applications specifically for food. For example, the 48 hours direct lactic acid vial for dressings and sauces, the orange serum broth vial for low pH and beverage applications, and the alicyclobacillus vial for beverages.

Validation strategies for both systems also varied because of market requirements. For example, in the food industry, companies seeking certain SQF level certifications require an AOAC approval on all methods used. Meaning that food testing validations were done according to the outlines and recommendations provided by AOAC International.

In addition, Neogen’s industry leading customer and technical service are now supported by the microbiological excellence of the staff from BioLumix. Both systems come with packages and programs for installation qualification, operational qualification and performance qualification. Furthermore, both systems have packages available to maintain the system through preventative maintenance programs.

Which system is right for you? It depends on the type of products manufactured, and the requirements. Neogen would be happy to help you understand the advantages of both systems and provide more information that can help you make the correct decision. You can contact Neogen by calling 800-234-5333 or emailing


The value of raw material screening for dietary supplement and nutraceutical companies

By Joe Heinzelmann

Raw material screening is an important part of 21 CFR 111. The current aspects of 21 CFR 111 do not put the burden of raw materials on the raw material manufacturer. The burden of the products from a compliance stand point lies within the manufacture of the product, and the brand holder. They do however have to follow 21 CFR 110, food processing cGMPs and are less stringent.

The testing requirements for dietary supplements and nutraceutical companies for raw materials under 21 CFR 111 is in sup part E, 111.75. Sup part E, section 75 states that one test must be completed to verify the identity of the compound before use. Before testing raw materials for microbial content, there are a few important considerations.

Key questions:

  • Does the process using this raw material undergo a microbial reduction step?
  • Does the screening cost (including holding time costs), outweigh the possibility of a rejected lot?
  • Does the manufacture have a long standing record of providing materials within your critical limits?
  • Are there antimicrobial properties of the ingredient? And will it be diluted when used in the final product formulation?

Setting specifications for raw materials will help determine if microbial testing should be completed before use. For example, if a product contains antimicrobial properties, and is diluted in a final product, the dilution of the anti-microbial properties could allow for microorganisms to grow. In this example, a lower specification could be used to screen out raw materials that would create problems to the final product when the antimicrobial properties are diluted.

Once limits and testing regimes have been determined for raw materials, another critical aspect to consider are the implications on the manufacturing process and the supply chain. If adding new testing points for total aerobic count (TAC), and yeast and mold (TYM), considerable time can be added to the entirety of the process.

When considering the supply chain of raw materials, and the manufacturing process, the total test time for total aerobic count, and total yeast and molds is critical. Adding 5-7 days of testing time on raw materials can be detrimental for manufacturing, and ruin just-in-time inventory practices. The BioLumix system allows for additional microbial testing controls, without the burden of long wait times.

The BioLumix system comes with a validation book, which helps provide users and auditors the needed data to show that the system is compliant and validated. Additionally, the BioLumix system can be validated against USP standards following the USP <1223> requirements.

For additional references, Michael McGuffin, President of the American Herbal Products Association, provided a useful overview of 111 compliance at a recent seminar. NSF provides training resources and support through their Dietary Supplement and Sports Nutrition groups.



Bacillus cereus contamination can lead to serious consequences…

By Jennifer Johnson

A couple of recent incidents have brought Bacillus cereus back into focus. In the UK for example, liquid baby formula contaminated with the bacteria killed one premature baby and was responsible for sickening 14 others in six different hospitals. Then, in China, 139 people become sick after consuming fermented
black beans
(douchi) in Yunan. After studies were done on vomit samples and the unprepared douchi, three Bacillus cereus strains were isolated.

Bacillus cereus is an aerobic and facultatively anaerobic, motile, spore-forming gram-positive rod.  B. cereus exists in two forms: spores and vegetative cells.  Because B. cereus is found in soil, so raw plant foods such as rice, potatoes, peas, beans and spices, are common sources of the organism. The presence of the organism in processed foods results from the contamination of the raw materials and the subsequent resistance of the spores to thermal and other manufacturing processes. During food’s cooling process, spores may germinate, enabling B. cereus to multiply and produce high levels of the emetic toxin cereulide.

After consumption of contaminated foods, B. cereus causes two types of gastroenteritis. One is an emetic syndrome with a relatively short incubation period of 1-6 hours that results in nausea and vomiting. The other is a diarrheal syndrome with an incubation period of 6-24 hours causing watery diarrhea, abdominal cramps, and pain.

This quick onset of symptoms can pose a serious problem for passengers on an
international flight for example, where many people can become sick in a short period of time. While foodborne illness associated with air travel is quite uncommon, foodborne outbreaks have been recorded by the airline industry as a result of improper testing or handling of food. When this does occur, it can have serious implications for passengers and crew members and means quality, safe, in-flight catering must rely on high standards of food preparation and storage; this applies at the airport kitchens (or at subcontractors’ facilities) and on the aircraft.

Bacillus cereus has also been recognized as a cause of potentially fatal systemic infections outside the GI tract, particularly in high-risk patients, such as infants, immune-compromised individuals, and chronically debilitated or elderly patients.  These infections include bacteremia, septicemia, meningitis, cerebral abscess, pneumonia, and endocarditis.

The risk of illness after ingestion of vegetative B. cereus cells is influenced by the strain, composition of the food, the liquid nature of the food and the age of the individual. Young children are particularly susceptible and may be more severely affected by a B. cereus contamination resulting in severe complications and even death. Because liquid foods, such as infant formula, are transported faster to the small intestine they are protected from the influence of gastric conditions, providing more opportunity for the survival of the pathogen.

BioLumix B. cereus Vial:

Detecting B. cereus as quickly and easily as possible is of paramount importance when corrective action(s) can minimize public exposure. BioLumix has an assay that detects B. cereus in 24 hours. The B. cereus vial’s sensor detects production of CO2. The disposable vial contains a transparent solid sensor located at the bottom which changes its optical properties whenever CO2 diffuses into it. Only gases can penetrate the sensor; blocking liquids, microorganisms, and particulate matter. Consequently, the optical readings are not masked by the sample. CO2 generated by B. cereus metabolism in the liquid medium placed above the sensor, diffuses into the sensor and interacts with an indicator reagent to provide an indication of the presence of the carbon dioxide. The medium contains growth promoting ingredients and inhibitors to gram-negative and non-Bacillus cereus gram-positive organisms.  The method used is very simple; just pipette the diluted sample into the vial and your results can be obtained in 24 hours or less.

Advantages of BioLumix Vials:

  • Vials can be stored at room temperature
  • Prefilled ready-to-use vials come with a Certificate of Analysis
  • Automated same day test results
  • Vials are available for a variety of tests, each with organism-specific enrichment medium
  • A single organism can be detected in a vial, if capable of growth in the medium
  • Liquid culture from a vial can be used to perform further tests


Year-end wrap up: Rapid microbiology in 2014

By Gerry Broski and Ruth Eden

To those people who still honor the tradition of sending out hard copy holiday cards, it has become quite popular for families to include a “year in review update,” which updates children’s ages, significant family events and, for those that are retired, travel destinations which have been checked off the bucket list. Electronically, this is our company update and we’ll send out the electronic holiday cards later this month.

As the year comes to a close and we review input from our customers, our market data indicates that in test method evaluation our customers are looking for higher specificity, faster time to results, and a reasonable cost-per test. They also want flexibility so that the testing platform can adapt to a number of matrices. Other factors include ease of use, robustness, and a test that is approved or can be approved. These factors above must be compelling enough for a company to switch from their existing method and adopt new technology, and it’s not just the QC or QA staff who are in the evaluation loop.

I recently went on a sales call to a company which was evaluating one of our rapid micro systems for the detection of spoilage organisms, and the conversation between the QA manager and the plant manager was enlightening. While the test would involve more work and cost for the QA department, the direct benefit would be realized for the plant manager since the product could be shipped with a much shorter quarantine period, resulting in increased throughput, and significant cost saving by compressing the sales cycle.  Summary:  Cost for QA, benefit for Operations.

That being said, automated rapid detection of microorganisms is a proven process which meets the customer criteria on several levels. It is sensitive and rapid, it can be used on almost all matrices, it involves less touch-time, takes up less space than plating or film methods, and offers a good value on a cost-per test basis. When one considers that it is essentially a “load and leave” test when interfaced to a LIMS system, the benefits are clear.

Suren Zatikyan from Wepackitall commented “When we discovered the BioLumix system, we found it gave us the opportunity to generate results in a very short period of time.  In addition, validation studies that were performed by BioLumix and later confirmed by us, proved that the system is compatible with the standard methods used by USP and other standard methods developed for microbiology labs. We use the BioLumix system to perform some of our environmental testing and monitoring programs, which is very helpful to us.”

Kristopher Flores from Wepackitall added “If the BioLumix system wasn’t in place, it would be tougher to support our needs for testing and throughput. In some instances, based on our testing and our customers’ testing, we’ve been able to validate our processes in-house and eliminate third party validation. That saves time, money, and makes an impact on the big picture for our customers.”

Neogen now offers two platforms for rapid micro detection of spoilage organisms, the BioLumix System and the Soleris System.  The BioLumix system is geared toward applications which follow USP protocols including dietary supplements, cosmetics and toiletry, while the Soleris System facilitates testing in food matrices requiring AOAC approved methods.

With hundreds of BioLumix and Soleris systems in use, Neogen is the clear leader in rapid microbiology testing in dietary supplements and nutraceutical products and very strong in many market segments in the food industry with Soleris AOAC approved tests. From initial contact to the completion of the installation and beyond, our commitment is to provide unparalleled support and total customer satisfaction.

Other advantages include:

 you can count on our sales teams to respond quickly, with the focus on your needs and goals. In addition, we can quickly and easily show you the value and the ROI.

• Expertise 
– Knowing how the BioLumix or Soleris systems will work with your products gives you peace of mind. That’s why we test samples – your samples – for you.

• Compliance validation for BioLumix systems
 – If you are concerned about validation, here is more good news.  We provide complete SOPs along with a customized validation book which includes Installation Qualification (IQ), Operations Qualification (OQ) and Performance Qualification (PQ).

• Simplicity and Ease-of-Use 
– These easy to master systems offers a new level of productivity. Sample preparation takes less than 2 minutes. The BioLumix System offers certificate of analysis generation in as little as 24-48 hours.• Support – We are committed to satisfying our customers and providing unparalleled support.

The future looks bright for Neogen and the field of rapid microbiology as we continue our ongoing commitment to the evolution to our BioLumix and Soleris platforms based on customer feedback and technology gains. That being said, I would like to take this opportunity to express my appreciation to all of our valued customers with whom we have grown significantly with through the years. With your support will continue to evolve and offer you even more valuable products.


Laboratory Information Management System (LIMS) in the Microbiology Lab

By: Paul Dudley

Today’s microbiology laboratories can generate an extensive amount of data across a variety of technologies.  Labs are tasked with providing  test results and information that is vital to the success of the organization and the safety of its products.   Of course, businesses and consumers demand efficiency – the goal is not only to provide safe products, but to provide them as quickly as possible.  As labs are updated and become more modern, better methods of data management and record keeping may be necessary in order to maintain or improve efficiency.  Luckily, there is a means to achieve this: Laboratory Information Management Systems, or LIMS. [1]

LIMS are software-based information systems that allows labs to track and share data within their environment.  There are numerous LIMS software applications, both open-source and proprietary.  But all have the same general goal – to help streamline data management to improve efficiency while reducing overhead costs.  LIMS can provide significant time savings for all people involved in a project by improving data access.  [3]

Example diagram showing the concept behind a Laboratory Information Management System and how data & information can be shared within a laboratory environment.

There are many advantages that the incorporation of a Laboratory Information Management System has over a more manual, traditional laboratory.  Some of these include improved efficiency, the ability to go paperless, cost reduction, and compliance.  Keep in mind, there are quite a few options when it comes to implementing a LIMS system, and whether it was initially an open-source application or a purchased program, a great deal of customization is usually implemented.  So when we talk about advantages, some may be more often utilized than others.  But any of these features can be of great benefit, depending on the wants and needs of the individual lab.


Improved efficiency is easily recognized when you eliminate the potential for errors from manual data entry.  The greater the amount of samples being processed and the total workload, the greater the chance for an error.  On the other hand, LIMS streamlines data entry by automating the process.  This results in less downtime, faster access to data, and the ability for the LIMS to grow with the increasing needs of the lab.


Some LIMS programs will authorize users to either modify existing reports or create new ones.  Also, web-based applications can interface with the LIMS so users don’t need to work directly with the LIMS itself but rather can work with just the reporting modules that in turn query the database [5] .  QC Management can use LIMS for scheduling and Certificates of Analysis.  Another great ‘paperless’ feature of LIMS is the ability of some programs to hold all pricing information for tests, which allows invoices to be produced for online access or as PDF documents [5] .  There are many examples of projects for implementing a paperless lab and how they benefited their labs, and one example showed a 30-40% gain in resources as a result of going paperless [6] .

Cost Reduction

When it comes to management at an executive level, the proof is in the bottom line.  Successful businesses rely on effective cost management.  Total costs of operations come in many forms, including labor, resources, downtime, time-to-market,  and more.  LIMS can impact many of these costs of doing business.  For example, one laboratory that implemented a LIMS system reduced its capital investment by 50%, while productivity rose at multiple laboratories [3] .  Another lab saw a 50% increase in throughput two years after implementing their LIMS [7] .  When you consider the time savings, efficiency, and the resulting improvements in time-to-market, LIMS can significantly contribute to overall improvements in cost management.


Product safety continues to be scrutinized in every market – including Food & Beverage, Nutraceutical, Cosmetics, and Pharmaceuticals.  Regulatory requirements are implemented to help reduce the risk of contamination, and different products and ingredients require different requirements.  This makes LIMS very essential.  LIMS can assist in real-time monitoring and Quality Control.  Workflows can be managed, samples logged, and tests can be checked against protocols and procedures to ensure compliance.  Out-of-spec samples can be reported automatically and flagged.   Reports can be automatically generated, and access to this information can be quickly gained by QC.  The overall increase in a structured approach via LIMS ensures compliance as business grows and throughput needs increase.

Neogen Corporation provides Rapid Microbiology Method (RMM) platforms such as BioLumix and Soleris.  Both systems can interface and exist within a LIMS environment.  For more information, visit or go to

The BioLumix system provides a single platform for all microbiology assays available for that system, allowing a large variety of tests without the need of additional equipment.  And its versatile – the modular design allows it to grow to meet throughput needs.   Results of tests for assays such as Total Aerobic Count, Yeast & Mold, Salmonella, and many more can be obtained within 24-48 hours.  Tests are be monitored in real time, and a Certificate of Analysis is automatically generated.  The system validates to USP <51>, <61>, <62>, <2021>, <2022>, and <2023> [9] .  In addition, Environmental Monitoring and Water Testing can be performed on the same platform.

Other advantages of the BioLumix System:

• Fully automated, easy to use.
• Faster sample preparation
• Faster turnaround time
• Fully Validated - the system comes complete with IQ, OQ, PQ and all SOP  documentation
• Outstanding support

As mentioned before, there are too many LIMS vendors to mention in this document.  Some applications will be better suited than others for your specific needs. has an extensive list of vendors that provide LIMS systems, and they even break out the vendors by industry.  So if you are looking for something more suited for Cosmetics, or for Food & Beverage, you can find those subcategories within that site.  It’s not the end-all be-all of resources, but it might be a good place to start.

4. Ruth Eden, Ph. D., Neogen Corp.
5. Food Quality Magazine (


The Relevance of USP Methodology in Microbiology for dietary supplements and cosmetic products – Part 2

By: Jennifer Johnson

Routine microbiological testing carried out by the Nutraceutical,
dietary supplements, cosmetics and toiletry manufacturing industries is determined by regulatory requirements. This applies not only to what should be tested and when, but also to the methods that should be used. Whether the final product is sterile or non-sterile, the bioburden exists from the raw materials, throughout the process and/or within the product’s environment (e.g. water) to the final product. A critical review of the overall microbiological process will determine whether the final product will meet its acceptance criteria. In addition, any “objectionable” or “specified” microorganisms that may be encountered during the procurement of raw materials and the processing must be considered.

Whether you are testing a raw material, an in-process sample, final product, or the environment, you should be aware of the critical role that microorganisms play throughout the process. You should also be familiar with the various microbiological related documents needed to determine whether the SOPs, validations, and regulatory body documents are being maintained to assure the control required to permit the final product to enter the marketplace as safe.

The Unites States Pharmacopeia (USP) is a non-governmental organization. Their documents are recognized as an official compendia book of methods and standards for Pharmaceutical, nutraceutical, dietary supplements, cosmetics, and toiletries. The USP offers a variety of documents such as monographs (published standards) and general chapters. General chapters with numbers 1000 are considered informational chapters.

Nutritional and Dietary Supplement USP Chapters
Since June 25, 2010, all dietary supplement manufacturers have been required to comply with the Food and Drug Administration’s (FDA) current good manufacturing practices (cGMP’s) according to the guidance outlined in USP chapters,, and.

<2021> Microbial Enumeration Tests – Nutritional and Dietary Supplements – This chapter provides tests for the estimation of the number of viable aerobic microorganisms present in nutritional supplements, from raw materials to the finished products.

<2022> Microbiological Procedures for Absence of Specified Microorganisms – Nutritional and Dietary Supplements -
Good manufacturing practices require that objectionable organisms be absent from non-sterile nutritional and dietary products. A microorganism can be considered objectionable if it represents a potential health hazard to the user who is using the product as directed, or if it is capable of growing in the product.

<2023> Microbiological Attributes of Nonsterile Nutritional and Dietary Supplements - The development of the formulation of nutritional or dietary supplements includes an evaluation of raw materials and their suppliers and the contribution made to the products by each ingredient and the manufacturing processes. Guidelines to help determine the appropriate tests to establish the microbial content of each ingredient are found in chapter.

The BioLumix system can perform all of the microbiological assays needed to get the finished product to the marketplace faster than traditional methods.

1. Microbial results can be generated in 24-48 hours in assays such as Total Aerobic Count, Yeast and Mold, Escherichia coli, Salmonella, Staphylococcus aureus, and Pseudomonas aeruginosa while utilizing one system.
2. The system can analyze tablets, capsules, powder, liquid and viscous material without any product interference.
3. The BioLumix system has software that is 21 CFR Part 111 compliant and BioLumix generates a customized validation book for each of its customers that include: Installation qualification (IQ), Operational qualification (OQ), and Performance qualification (PQ).

For more information click here.

Cosmetic and Toiletry USP Chapters
There are three USP chapters that are most important to the cosmetics and toiletry industries, <51>, <61> and <62>:

<51> Antimicrobial Effectiveness Testing - The ultimate purpose of the Preservative Efficacy Test (PET) is to determine the effectiveness of the preservative(s) present in a cosmetic or toiletry product. USP Chapter describes the type of products to be tested (categories), the specified microorganisms to be used for testing, and the inoculum and log reduction amounts required per category of product. The product to be tested is inoculated with a high number of bacteria, yeast, and mold, and the reduction in the initial inoculum amount is calculated over a 28 day period.

<61> Microbiological Examination of Nonsterile Products: Microbial Enumeration Tests - Suitability testing is performed in order to verify that the method utilized eliminates the effect of any antimicrobial properties of the product. Therefore, the media diluent combination does not inhibit the recovery and growth of microorganisms, if present in the sample. The goal of the suitability testing is to establish the ability of the test to detect microorganisms in the presence of product. The suitability described in USP verifies the validity of the testing method by showing the recovery of microorganisms in presence of the product.

Microbiological Examination of Nonsterile Products: Tests for Specified Microorganisms – Suitability testing using USP is performed by using selective media to detect various organisms such as: Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, bile-tolerant gram-negative bacteria, Clostridia, Salmonella and Candida albicans in the presence of the product. The samples are first enriched by incubating in Trypticase Soy Broth (TSB) or another appropriate neutralizing media, and then streaked onto selective agars for the determination of presence of specified or the objectionable microorganisms.

The Relevance of USP Methodology in Microbiology in Pharmaceuticals

The Relevance of USP Methodology in Microbiology in Pharmaceuticals

By Jennifer Johnson

Routine microbiological testing carried out by the pharmaceutical, cosmetics and toiletry manufacturing industries is determined by regulatory requirements. This applies not only to what should be tested and when, but also to the methods that should be used. Whether the final product is sterile or non-sterile, the bioburden exists from the raw materials, throughout the process and/or within the product’s environment (e.g. water) to the final product. A critical review of the overall microbiological process will determine whether the final product will meet its acceptance criteria. In addition, any “objectionable” or “specified” microorganisms that may be encountered during the procurement of raw materials and the processing must be considered.

Whether you are testing a raw material, an in-process sample, final product, or the environment, you should be aware of the critical role that microorganisms play throughout the process. You should also be familiar with the various microbiological related documents needed to determine whether the SOPs, validations, and regulatory body documents are being maintained to assure the control required to permit the final product to enter the marketplace as safe.

The Unites States Pharmacopeia (USP) is a non-governmental organization. Their documents are recognized as an official compendia book of methods and standards for Pharmaceutical, nutraceutical, dietary supplements, cosmetics, and toiletries. The USP offers a variety of documents such as monographs (published standards) and general chapters. General chapters with numbers <1000 are mandatory chapters and numbers >1000 are considered informational chapters.

Pharmaceutical USP Chapters

USP offers some standardized test methodologies and material specifications relating to microbiological quality and control so as to ensure product quality and safety.

<1111> Microbiological Examination of Nonsterile Products: Acceptance Criteria for Pharmaceutical Preparations and Substances for Pharmaceutical Use – It is suggested that certain categories of products should be tested routinely for total microbial count and for specified indicator microbial contamination.  The relevant tests for determining the total count of viable aerobic microorganisms and the total combined yeast and mold count and for detection and identification of designated species are given under Microbial Limit Tests <61>.

<1115> – Bioburden Control of Nonsterile Drug Substances and Products – This chapter deals with the bioburden of non-sterile drug substances and products. The chapter states that the biggest manufacturing risk for these products is the ingredient water.  Process water is the single most important risk factor contributing to the contamination of nonsterile products.  The purified waters that are used in manufacturing are deionized and do not contain chlorine that helps control microbial growth.  Purified water is capable of supporting growth of gram negative rod shaped bacteria and many different molds.

For more information, click here.

<1116> Microbiological Control and Monitoring of Aseptic Processing Environments – The purpose of this chapter is to review the various issues that relate to aseptic processing of bulk drug substances, dosage forms, and to the establishment, maintenance, and control of the microbiological quality of controlled environments.

For more information, click here.

<1117> Microbiological Best Laboratory Practices - This general information chapter outlines what is needed to improve the effectiveness, efficiency and inspection-readiness of a Microbiology Laboratory in respect to media preparation, microbiological cultures, lab equipment, laboratory layout, lab records, interpretation of results, training, and documentation.

<1223> Validation of Alternative Microbial Methods – The purpose of this chapter is to provide guidance for validating methods for use as alternatives to the official compendial microbiological methods.  Validation of microbiological methods is the process by which it is experimentally established that the performance characteristics of the method meet the requirements for the intended application, in comparison to the traditional method.  Traditional plate methods for microbiological testing require long time to results, highly trained microbiologists, is labor intensive, and creates a bottleneck for product release.  Rapid microbiological methods (RMMs) offer a high degree of automation, significant reduction in time to results, reduced staff training, faster product release, and improved process control.

<1227> Validation of Microbial Recovery from Pharmacopeial Articles – This chapter
provides guidelines for the validation of methods for the estimation of the number of viable microorganisms, for the detection of indicators or objectionable microorganisms, for the validation of microbiological methods used in antimicrobial effectiveness testing, and for the sterility testing of Pharmacopeial articles. It is generally understood that if a product possesses antimicrobial properties because of the presence of a specific preservative or because of its formulation, this antimicrobial property must be neutralized to recover viable microorganisms. This neutralization may be achieved by the use of a specific neutralizer, by dilution, by a combination of washing and dilution, or by any combination of these methods.

<1231> Water for Pharmaceutical Purposes – According to USP <1231>, although there are no absolute microbial standards for water (other than water intended to be sterile), the cGMP regulations require the establishment of appropriate specifications. The specification must take into account the intended use of the water; i.e., water used to formulate a product should contain no organisms capable of growing in the product. Action or alert limits should be established based upon validation data and must be set low enough to signal significant changes from normal operating conditions.

BioLumix Rapid Microbiology Methods offer innovative new testing solutions that are designed specifically for the challenges of the pharmaceutical industry, including a multitude of microbial tests for raw materials, in-process and finished products, as well as, the capacity to perform environmental and water testing. This simplifies, expedites, and reduces the cost of performing microbiological assays.

The BioLumix Drug Master File (DMF) entitled “Microbiological Rapid Method for the Detection and Enumeration of Microorganisms in Pharmaceutical Products” has been accepted by the US Food and Drug Administration (FDA). The DMF provides specific technical and regulatory information to the FDA which allows companies planning to use the BioLumix Rapid Microbiological System to obtain regulatory approvals for prescription drugs.  The DMF can be referenced by drug manufacturers, reducing FDA review times and accelerating the regulatory approval process for use of the BioLumix System. In addition, Over the Counter (OTC) products can be tested in conjunction with the BioLumix Validation Package.

 For more information, click here and here.

The Importance of Suitability Testing

Posted by Caron Ockerman

Many pharmaceutical, cosmetic, and toiletry products contain preservatives that help extend the product’s shelf life, keeping spoilage at bay for a certain period of time, and also act with antimicrobial properties if microbes are introduced.  A consumer dipping a finger into a jar of facial cream has introduced microbes into the cream, and the preservative should effectively kill or reduce the number of microorganisms (for more information on preservative effectiveness, please read the blog “Preservative Efficacy Testing: Guidelines to an Automated Simplified Testing System”).

Why we need suitability testing? The measurement of preservative test requires the ability to count the number of surviving microorganisms after exposure to the antimicrobial agent in the product.  Bioburden (also called microbial content) testing has the same requirement because the assay depends on the ability to recover viable microorganisms in the presence of potentially antimicrobial in the product or raw materials. Carryover of residual inhibitors from the product could inhibit growth in the recovery medium, leading to poor microbial recovery. This potential residual activity must be neutralized and it is necessary to demonstrate the adequacy of neutralization for the test. This demonstration of neutralization in compendial microbiological tests is known as demonstration of method suitability.

Therefore, before conducting any microbiological test, it is important to find the most effective neutralizing agent or dilution that will create a suitable environment for growth, allowing for accurate results during microbial content and preservative efficacy testing.

How to test for Suitability- Suitability in the presence of product is the ability of microorganisms to grow when introduced in low numbers.  Following the plate count method for suitability in USP Chapter <61> MICROBIOLOGICAL EXAMINATION OF NONSTERILE PRODUCTS: MICROBIAL ENUMERATION TESTS, the appropriate growth media alone (control) and the product (test) are inoculated with 10-100 cfu.  The inoculated product is then diluted 1 to 10.   If growth occurs on control plates, but does not grow on test plates, or counts are half that of the control plates, neutralization or further dilution may be necessary to show suitability of product.

How to Neutralize Inhibitors- Depending upon the type of product and the inhibitory system being tested, different diluents should be used as some products may require neutralization of a strong preservative that would suppress growth of naturally occurring microbes.  Table 1 below summarizes some neutralizing agents used in common neutralizing broths such as Modified Letheen Tween (MLT) broth, D/E Neutralizer, and Tryptone Azolectin Tween (TAT) broth among others.

Sometimes, even the use of a neutralizing agent may not be enough, and dilution further than 1 to 10 may be necessary.  It is important to keep in mind that five different organisms are being tested in one product, and what allows one organism to grow might not work as well for another.  Essentially, it is important to find any and all different parameters that make a product suitable for inoculation.

Once a proper neutralizer or dilution is found for each product and organism, microbial content testing and PET testing can proceed.  Without performing suitability testing first, microbial content testing and PET may yield false negative results; bacteria, yeast or mold may be present, but simply remain dormant until the optimal growth conditions are introduced.

The suitability test can be performed very simply and quickly with the BioLumix system.

Use of BioLumix System for suitability testing- The BioLumix system is capable of determining whether a product meets suitability standards.  Products and controls are inoculated, then 1.0 mL is added to the BioLumix vials, entered into the instruments, and initial results may be observed within 18-24 hours.  The figure shows examples of curves obtained from the BioLumix system using Staphylococcus aureus with various preservative systems.  The top picture shows a product that is properly neutralized. While as the bottom picture demonstrates that without proper neutralization, product can hinder the growth of organisms.

In the BioLumix instrument, if the detection time (DT) of the media without product is within a couple of hours of the product containing media it means that enough neutralization is achieved. If there is a DT without the product in the positive control; but the sample containing vial does not have a DT it means that the product prevents the growth of bacteria and a different neutralization scheme needs to be employed.

What are the advantages of the BioLumix system?
Time Saving: The results are available much faster, for example, the results of the Yeast and Mold vials occurred in less than 48 hours, instead of five days for countable colonies. All products tested with bacteria using the automated BioLumix assay yielded results typically within 10-18 hours, instead of 48 hours for the plate count methodology. The advantage using the BioLumix system is that you can see results an entire day earlier if the product is exhibiting any sort of inhibition.

Labor Saving: The setup of the assay can be done much faster using the BioLumix system as opposed to traditional plating methods, saving significant hands-on labor due to its automation and simplicity of use.

High Correlation with USP: The BioLumix System showed a high correlation between the instrument results and the USP methodology.