Location: Meat Safety and Quality
Title: Evaluation of the post-enrichment process times for commercial E. coli O157:H7 molecular detection systemsAuthor
Bosilevac, Joseph - Mick | |
AHMED, MOHAMMED - Biomerieux, Inc | |
DUTTA, VIKRANT - Biomerieux, Inc |
Submitted to: Journal of Food Protection
Publication Type: Abstract Only Publication Acceptance Date: 5/1/2020 Publication Date: 8/2/2020 Citation: Bosilevac, J.M., Ahmed, M., Dutta, V. 2020. Evaluation of the post-enrichment process times for commercial E. coli O157:H7 molecular detection systems. [Abstract]. International Association for Food Protection Conference, Cleveland, Ohio, August 2-5, 2020, Virtual. Journal of Food Protection. 83(Supplement A):P1-98. Interpretive Summary: Technical Abstract: Introduction: The high sensitivity of DNA-based rapid pathogen detection systems has significantly improved total time to results (TTR). However, production for food commodities such as ground beef and produce still remains a time sensitive endeavor, such that seemingly small differences in time can have significant impact on the overall operation. Purpose: This study compared the post-enrichment process time for five commercial E. coli O157 including H7 molecular detection systems. Methods: Simulated 325 g+975 mL post-enrichment samples (n=8) were processed through A: BAX, B: GENE-UP, C: GDS, D: iQCheck, and E: MDS, as per the respective package inserts with time (seconds) of each step recorded for two independent users, repeated 3 times. Steps were classified as manual or machine time for steps within three categories: lysis (template preparation), PCR (reaction set up), and instrument (software interaction plus machine run-time). For the time estimation of TTR for a full instrument load (72 to 96 samples), the manual times were projected by a factor of 11 (A,B,D,E) or 8 (C) based on required controls and thermocycler capacity, while the machine time remained the same. Results: The post-incubation TTR were 11,952, 15,110, 16,141, 15,515, and 26,185 sec, for B, E, A, C, and D respectively. Most systems spent the least amount of time on the PCR set up ~1000-7000sec; B-lowest, E-highest. Next was the lysis template preparation ~5000-10000sec; B-lowest and C-highest, followed by the most on the instrument ~5000-18000sec; B-lowest and D-highest. Overall, B was about 80% less time consuming than A, C and E; while A, B, C, and E were about half as time consuming as D for manual manipulation and instrumentation. Significance: To our knowledge, data evaluating the processing times between commercial PCR systems has not been published. These data can serve as a guideline for time sensitive food industries examining PCR methods. |