AOAC 133rd Annual Meeting - Final Program

Poster Abstracts | Wednesday

P-W-082 Renaud Tremblay , Afia Boumail , Alex Eyraud , Mounia Akassou , Jean-Félix Sicard , Sergiy Olishevskyy , FoodChek Laboratories Inc., Ste-Julie, QC, Canada; Michael Giuffre , FoodChek Systems Inc., Calgary, AB, Canada Validation of a Modified Version of Actero™ Salmonella Enrichment Media for Rapid Detection of Salmonella in Environmental Surface and Food Samples The Actero™ Salmonella Enrichment Media is a bacterial culture broth specifically developed to improve the recovery of Salmonella spp. from foods and environmental surfaces. Its performance has already been assessed and validated for the detection of Salmonella in various foods, feeds and environmen- tal surface samples using different platforms. This study aimed to validate the performance of a modified version of Actero™ Salmonella incorporating one of the two liquid supplements into the powdered base formula. Inclusivity, exclusivity, stabil- ity and lot-to-lot studies were carried out. Performance of the broth was also evaluated in method comparison studies on raw ground beef (375 g), chicken carcass rinse (30 mL), dry pet food (375 g) and stainless-steel (100 cm 2 ) sponge samples. After enrichment of 14-20 h at 35-39°C, the samples were analyzed using Real-Time PCR Assay for Salmonella as well as by direct plating. The Probability of Detection statistical model confirmed equivalent performance of the alternative method as compared to the USDA-FSIS MLG 4.10 and BAM Chapter 5 methods. No false negative or positive outcomes were detected among 120 food and environmental samples analyzed by the alternative method. The incorporation of one of the two specific selective growth substrates and stimulating co-factors, previously used as liquid supplements, into a powdered formulation of Actero™ Salmonella made it more convenient without compromising on performance and reliability. Presenter: Renaud Tremblay, FoodChek Laboratories Inc., Ste-Julie, QC, Canada, Email: rtremblay@foodcheksystems.com P-W-083 Hanna Hartenstein , Benjamin Junge , Cordt Grönewald , Kornelia Berghof-Jäger , BIOTECON Diagnostics, Potsdam, Germany Development of a Multiplex Real-Time PCR Kit for the Detection of Food-Relevant Listeria Species and Identification of Listeria Monocytogenes in a Single Reaction Listeria Monocytogenes is considered to be one of the most important food-borne pathogens. It can cause severe disease, including meningoencephalitis, and abortion, with mortality rates up to 33%. Infections have been traced to the consumption of contaminated foods that often have relatively short shelf lives, emphasizing the need for rapid detection methods. L. monocy- togenes is often found in samples that contain other Listeria spp. Therefore, the detection of Listeria species is often used as an indicator for the presence of L. monocytogenes . We developed the foodproof Listeria plus L. monocytogenes Detection LyoKit, a rapid, accurate and sensitive real-time PCR method for the

simultaneous detection of food-relevant Listeria species and a specific identification of pathogenic L. monocytogenes in a single reaction. Presenter: Hanna Hartenstein, BIOTECON Diagnostics, Potsdam, Germany, Email: hhartenstein@bc-diagnostics.com P-W-084 Benjamin Katchman , PathogenDx, Tucson, AZ, USA Validation Study Demonstrates DNA Microarray Use as a High-Throughput Diagnostic Tool Offers an Ultra- Rapid Result for the Qualitative and Quantitative Detection of Bacterial and Fungal Pathogens The field of cannabis, food, water, and agricultural safety, has increasingly complex panels of pathogens that must be tested in parallel. The large volume of products and wide range of pathogens which must be tested in order to ensure safety are not sustainable under the current diagnostic standard. Plate-based diagnostics are time and labor intensive and lack the sensitivity and specificity required to maintain the current pace to protect public safety. The DNA microarray technology, by PathogenDx, combines multiplexed PCR with specific single stranded DNA probes fixed to a glass microscope slide to detect and quantify a variety of bacterial and fungal pathogens in under 8 hours with- out the need for sample enrichment. The Detect X array contains probes for E. coli , S. enterica, A. niger, A. fumigatus, A. terreus, and A. flavus with the ability to detect organisms at 1 CFU/gram at 90% sensitivity and 100% specificity compared to plating. The Quant X array contains probes specific for Total Aerobic, Bile Tolerant Gram Negative, Total Enterobacteriaceae/ Coliform and Total Yeast and Mold reporting values as CFU/gram. We demonstrate linearity for all probes (R 2 ≥ 0.9), probe specificity and concordance in comparison to plating with a dynamic range of 10 2 to 10 6 CFU/gram. This technology emphasizes a break- through in molecular diagnostics allowing multiplexed detection at a sensitivity and specificity unmatched by similar molecular diagnostic platforms with broad applications. Presenter: Benjamin Katchman, PathogenDx, Tucson, AZ, USA, Email: bkatchman@pathogendx.com P-W-085 Hanna Hartenstein , Benjamin Junge , Florian Priller , Cordt Grönewald , Kornelia Berghof-Jäger , BIOTECON Diagnostics, Potsdam, Germany AOAC PTM Validated Vibrio Detection Method for Species and Toxigenicity Genes Identification Using Real-Time PCR Vibrio parahaemolyticus, V. vulnificus and V. cholerae are known to be potential waterborne contaminants of seafood and cause severe health problems worldwide. Traditional methods for the detection are time consuming and error-prone, while qPCR can be done in less than 24 h including enrichment with a high specificity and sensitivity. Our real-time PCR assay discriminates between V. parahaemolyticus, V. vulnificus and V. cholerae and simultaneously detects and identifies the pathogenicity factors ctx, tdh, trh 1 and trh 2 by melting curve analysis in just

108 SEPTEMBER 6–12, 2019 SHERATON DENVER DOWNTOWN HOTEL