Enhanced rapidity for qualitative detection of Listeria monocytogenes using an enzyme-linked immunosorbent assay and immunochromatography strip test combined with immunomagnetic bead separation.
An enzyme-linked immunosorbent assay (ELISA), immunochromatography (ICG) strip test, and immunomagnetic bead separation (IMBS) system based on a monoclonal antibody were individually developed for the detection and isolation of Listeria monocytogenes in meat samples. The three methods showed a strong reaction with Listeria species and a weak reaction with Staphylococcus aureus. To increase the rapidity of L. monocytogenes detection, combinations of the ELISA and ICG strip test with the IMBS system (ELISA-IMBS and ICG-IMBS) were investigated. In comparative analyses of artificially inoculated meat and samples of processed meat, the ELISA and ICG strip test required 24 h of enrichment time to detect the inoculated meat samples with > or =1 X 10(2) CFU/10 g, whereas the ELISA-IMBS and ICG-IMBS required only 14 h of enrichment. Analyses of naturally contaminated meat samples (30 pork samples, 20 beef samples, 26 chicken samples, 20 fish samples, and 20 processed meat samples) performed by ELISA-IMBS, ICG-IMBS, and API kit produced similar results. The ELISA-IMBS and ICG-IMBS provide a more rapid assay than the individual ELISA and the ICG strip test and are appropriate for rapid and qualitative detection of L. monocytogenes (or Listeria species) in meat samples. With the ICG-IMBS, L. monocytogenes could be detected in meat samples within 15 h and the method has potential as a rapid, cost-effective on-site screening tool for the detection of L. monocytogenes in food samples and agricultural products at a minimum detection level of approximately 100 CFU/10 g.
Shim
Won-Bo
WB
Division of Applied Life Science (Brain Korea 21 program), Graduate School of Gyeongsang National University, Chinju, Gyeongnam 660-701, Korea.
Choi
Jin-Gil
JG
Kim
Ji-Young
JY
Yang
Zheng-You
ZY
Lee
Kyu-Ho
KH
Kim
Min-Gon
MG
Ha
Sang-Do
SD
Kim
Keun-Sung
KS
Kim
Kwang-Yup
KY
Kim
Cheol-Ho
CH
Eremin
Sergei A
SA
Chung
Duck-Hwa
DH
D000911:Antibodies, Monoclonal / Q000096:biosynthesis; D015169:Colony Count, Microbial; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D005506:Food Contamination / Q000032:analysis*; D007118:Immunoassay / Q000379:methods*; D018189:Immunomagnetic Separation / Q000379:methods*; D008089:Listeria monocytogenes / Q000276:immunology / Q000302:isolation & purification; D008460:Meat / Q000382:microbiology*; D008461:Meat Products / Q000382:microbiology; D011934:Reagent Strips; D012680:Sensitivity and Specificity; D013045:Species Specificity; D013211:Staphylococcus aureus / Q000276:immunology / Q000302:isolation & purification; D013997:Time Factors
D000911:Antibodies, Monoclonal; D011934:Reagent Strips