New DNA-Based Assay Rapidly Detects E. coli O157:H7 During Food Manufacture

By LabMedica International staff writers
Posted on 18 Nov 2015

A rapid DNA-based test for the detection of the serious food borne pathogen E. coli O157:H7 joins a line of innovative assays designed for use by the food industry.

The ANSR E. coli O157:H7 kit is a welcome addition to Neogen Corporation’s (Lansing, MI, USA) ANSR tests for Salmonella, Listeria, and Listeria monocytogenes.

Image: The ANSR (Amplified Nucleic Single Temperature Reaction) system incorporates advances in DNA detection technology resulting in a system that is easy to use and provides much faster results than PCR systems (Photo courtesy of Neogen).

Neogen's ANSR (Amplified Nucleic Single Temperature Reaction) platform incorporates advances in DNA detection technology resulting in a method that is easy to use and provides much faster results than PCR systems. ANSR was designed to address in-plant testing needs and offers the freedom to economically process samples to meet regulatory requirements and ensure food safety.

ANSR uses isothermal amplification to create a level of molecular target material that can be detected using fluorescence. The system's DNA amplification methodology exponentially amplifies the DNA of any target bacteria present in an enriched food sample to detectable levels in only minutes. Target nucleic acid is amplified through a mechanism of polymerization from the ends of nicks created in double-stranded DNA by the action of a specific endonuclease. Amplified target sequences are detected in real time using fluorescent molecular beacon probes.

To date, the assay has been validated for testing raw ground beef, raw beef trim, leafy greens, and sprout irrigation water. The system has exhibited low matrix effects with high sensitivity and provides both positive and negative results in minutes.

"The well-received and validated ANSR system provides the food industry definitive test results, and much easier and quicker methodology," said Ed Bradley, vice president of food safety at Neogen. "This introduction of ANSR for E. coli O157:H7 extends our ANSR product offering for the bacterial pathogens of greatest concern to the food industry, and will be very easy for laboratories to adopt, as it follows the same procedure of all our other ANSR kits."

Related Links:
Neogen Corporation