28
Using the ChromID OAA and ChromID Lmono agars allowed for faster, easier detection of
L. monocytogenes
colonies compared to
1
the traditional selective isolation agars. The results of this study demonstrate the reliability of the VIDAS
®
LMX method when
2
compared to traditional reference methods for the detection of
Listeria monocytogenes
in foods.
3
4
Overall Results
5
Overall the LMX method was equivalent to the reference methods for detection of
L. momocytogenes
in the PTM and GovVAl
6
comparative food evaluations; however, in the GovVal study better recovery was observed for LMX when compared to the Health
7
Canada MFHPB-30 method. There were no false positive results for any of the uninoculated samples using the LMX method.
8
Confirmation using chromogenic agars OAA and Chrom ID L.mono showed exact agreement.
9
10
Overall Conclusions (PTM and GovVal Evaluations)
11
12
The results of these studies demonstrate that the VIDAS
®
LMX method was equivalent to traditional reference methods for the
13
detection of
Listeria monocytogenes
in foods. Confirmation of presumptive LMX results with the chromogenic OAA and Lmono
14
media were equivalent to the reference agars used in this study for all foods tested. The VIDAS
®
LMX method offers a significant
15
savings in time when compared to the traditional reference methods by giving presumptive results in a minimum of 26 hours.
16
17
References
18
19
1. Seeliger H.P.R., Jones D., Sneath P., Mair N., Sharpe M. E. & J Holt (1986)
Bergey’s Manual of Systematic Bacteriology
, Vol. 2,
20
1235-1245
21
2. Rocourt J., Boerlin P., Grimont F., Jacquet C., & Piffaretti J.C. (1992)
Int. J. Syst. Bacteriol.
42
, 69-73
22
3. Baron, E.L., Jorgensen, J.H., Landry, M.L., Murray, P.R., & Pfaller, M.A . (2007)
Manual of Clinical Microbiology
, 9
th
Ed.,
23
American Society for Microbiology, Washington, DC, pp 474–480 (1991)
24
4. U.S. Food and Drug Administration (2003)
FDA Bacteriological Analytical Manual,
25
http://www.fda.gov/Food/ScienceResearch/LaboratoryMethods/BacteriologicalAnalyticalManualBAM/UCM071400.26
5. U.S. Department of Agriculture, Food Safety and Inspection Service (2009)
Microbiology Laboratory Guidebook
,
27
http://www.fsis.usda.gov/PDF/MLG_8_07.pdf.28
6. AOAC Official Method 993.12 (1994)
Listeria monocytogenes
in Milk and Dairy Products
J. AOAC Int.
77
, 395
29
7. Health Canada, Health Products and Food Branch (2010)
Compendium of Analytical Methods
, MFHPB – 30,
http://www.hc-30
sc.gc.ca/fn-an/alt_formats/hpfb-dgpsa/pdf/res-rech/mfhpb30-eng.pdf.31
8. Feldsine P., Abeyta C., and Andrews W.H., (2002) AOAC INTERNATIONAL Methods Committee Guidelines for Validation of
32
Qualitative and Quantitative Food Microbiological Official Methods of Analysis,
J. AOAC Int.
85
, 1187-1200.
33
9. AOAC MPN Calculator,
http://www.lcfltd.com/customer/LCFMPNCalculator.exe.34
10. AOAC Official Method 992.19 (1993)
Listeria
species,
J. AOAC Int
.
76
, 822
35
11. AOAC Official Method 992.18 (1993)
Listeria
species,
J. AOAC Int
.
76
, 831
36
PTM Certification Report