This study describes a rapid method for the isolation and detection of Escherichia coli O157:H7 present at low levels (0.04–0.4 cfu/g) in fresh salad produce. Following a short enrichment (5 h at 42C), samples were processed using Pathatrix, a novel recirculating immunomagnetic capture system, linked to real-time polymerase chain reaction and/or selective agar plating. Processing of post-enrichment sample aliquots (10 mL diluted 1:25) and the use of preblocked paramagnetic anti-E. coli O157:H7 beads enhanced target pathogen recovery on selective agar plates in cases where a high microbial load of nontarget microflora was present. This is of particular relevance to the testing of bean sprouts. This method has the potential to provide a result within 7 h. The speed of result offers significant benefits for outbreak investigations and allows the rapid screening of salad produce for E. coli O157:H7 contamination prior to product entering the distribution chain.

REFERENCES

ARTHUR, T.M., BOSILEVAC, J.M., NOU, X. and KOOHMARAIE, M. 2005. Evaluation of culture and PCR based detection methods for Escherichia coli O157:H7 in inoculated ground beef. J. Food Prot. 68, 1566–1574.
10.4315/0362-028X-68.8.1566
CAS PubMed Web of Science® Google Scholar
BRACKETT, R.E. 2005. Letter to California firms that grow, pack, process, or ship fresh and fresh-cut lettuce. Office of Plant and Dairy Foods, USFDA/CFSAN. http://www.cfsan.fda.gov/~dms/prodltr2.html.
Google Scholar
FDA. 2006. FDA statement on foodborne E. coli O157:H7 outbreak in spinach. FDA press release PO6-167 October 12 2006. http://www.fda.gov/bbs/topics/NEWS/2006/NEW01489.html.
Google Scholar
FU, T.J., MAKS, N., PARISI, B. and SLADE, P. 2006. Evaluation of an automated immunomagnetic separation system for selective isolation of E. coli O157:H7, Salmonella and L. monocytogenes from inoculated spent sprout irrigation water. Poster L-16. FDA Science Forum 2006.
Google Scholar
HANES, D.E., SAYLOR, M.L., KOTHARY, M.H., LORENZO, M.E. and TALL, B.D. 2005. Isolation of Yersinia pestis from food using immunomagnetic capture. Poster N-14. FDA Science Forum 2005.
Google Scholar
HANES, D.E., KOTHARY, M.H., TALL, B.D., EDELSON-MAMMEL, S.G., BURR, D.H. and WEAGANT, S.D. 2006. Evaluation of the FDA-FERN screening method developed for the isolation and identification of Yersinia pestis from foods. Poster J-07. FDA Science Forum 2006.
Google Scholar
HIMATHONGKHAM, S., YEE, J., LAU, H., LIN, A. and LAU, D. 2006. Rapid and effective method to improve detection and isolation of Escherichia coli O157:H7 from fresh produce. Poster 3-53. IAFP Meeting 2006.
Google Scholar
LAU, H., LIN, A. and HIMATHONGKHAM, S. 2006. Detection of Escherichia coli O157:H7 in produce rinse by Pathatrix immunomagnetic extraction and conventional methods. 2006 FDA Laboratory Information Bulletin #4371.
Google Scholar
MADSON, S.M., LASTER, E.W., THOMAS, M.Z., WATTS, K.A. and SOFOS, J.N. 2006. A preliminary limited study on detection of Shigella sonnei from cantaloupe rinse by culturing with or without pre-enrichment, cell capture, and aerobic or anaerobic enrichment. Poster B-53. FDA Science Forum 2006.
Google Scholar
MMWR/CDC. 2006. Ongoing multistate outbreak of Escherichia coli serotype O157:H7 infections associated with consumption of fresh spinach – United States. Morb Mortal Wkly Rep 55, 1045–1046.
Google Scholar
MULLANE, N.R., MURRAY, J., DRUDY, D., PRENTICE, N., WHYTE, P., WALL, P.G., PARTON, A. and FANNING, S. 2006. Detection of Enterobacter sakazakii in dried infant milk formula by cationic-magnetic-bead capture. Appl. Environ. Microbiol. 72, 6325–6330.
10.1128/AEM.03056-05
CAS PubMed Web of Science® Google Scholar
STEVENS, K.A. and JAYKUS, L.-A. 2004. Bacterial separation and concentration from complex sample matrices: A review. Crit. Rev. Microbiol. 30, 7–24.
10.1080/10408410490266410
PubMed Web of Science® Google Scholar
WARREN, B.R., YUK, H-G. and SCHNEIDER, K.R. 2006. Sensitive and specific detection of Salmonella from ground beef and potato salad samples within eight hours. Poster 3-41. IAFP Meeting (in press).
Google Scholar
WU, V.C.H., GILL, V., OBERST, R., PHEBUS, R. and FUNG, D.Y.C. 2004. Rapid protocol (5.25 h) for the detection of Escherichia coli O157:H7 in raw ground beef by an immuno-capture system (Pathatrix) in combination with Colortrix and CT-SMAC. J. Rapid Methods Autom Microbiol 12, 57–67.
10.1111/j.1745-4581.2004.tb00047.x
CAS Web of Science® Google Scholar
YUK, H-G., WARREN, B.R. and SCHNEIDER, K.R. 2006. Preliminary evaluation of flow through immunocapture followed by real-time PCR for the detection of Salmonella serovars on tomato surfaces within 8 hours. J. Food Prot. 69, 2253–2257.
10.4315/0362-028X-69.9.2253
PubMed Web of Science® Google Scholar

Citing Literature

Volume14, Issue4

December 2006

Pages 299-308

RAPID ISOLATION AND DETECTION OF ESCHERICHIA COLI O157:H7 IN FRESH PRODUCE

ABSTRACT

REFERENCES

Citing Literature

References

Information

About Wiley Online Library

Help & Support

Opportunities

Connect with Wiley

RAPID ISOLATION AND DETECTION OF ESCHERICHIA COLI O157:H7 IN FRESH PRODUCE

ABSTRACT

REFERENCES

Citing Literature

References

Related

Information