Neogen Corporation has received approval from the AOAC Research Institute for its new 24-hour environmental sample enrichment protocol for Listeria.

Neogen’s approved new enrichment protocol is for use with either its Reveal® for Listeria ELISA lateral flow assay or GeneQuence® Listeria microwell DNA probe assay. Both of Neogen’s test systems for Listeria had been earlier AOAC-approved (Reveal #9607901, GeneQuence #010403); in both cases this new approval reflects the modification of the enrichment of environmental samples with Neogen’s new LESS 24-hour single-step Listeria medium.

"It’s gratifying any time a well-respected third party confirms the exceptional performance of our testing products," said Ed Bradley, Neogen’s vice president of Food Safety. "This AOAC approval is particularly important because it verifies the validity of a significantly improved method of Listeria testing. The new LESS medium was shown to produce accurate results in only 24 hours, as opposed to other test systems that can take twice as long. In addition, because it is a single-step medium, LESS eliminates the time and effort associated with Listeria test systems that require multiple enrichment media."

Neogen’s Reveal for Listeria provides a very easy method of screening environmental samples for the presence of the pathogen. Just add an enriched sample to the testing device, and a clear result is available in about 15 minutes.

GeneQuence Listeria and GeneQuence Listeria monocytogenes are assays that combine DNA hybridization technology with full automation capability to provide rapid, highly accurate results. GeneQuence’s ability to test relatively few samples manually, or large numbers automatically, provides easy method standardization for companies with many testing facilities with varying test volumes.

In validation studies, LESS medium demonstrated superior recovery performance when used with swabs and sponges that sampled various environmental surfaces. LESS medium dramatically increased the recovery of stressed Listeria cells spiked onto the surfaces, and all positives detected with LESS were confirmed using the standard BAM culture method.