Rapid MPN-Qpcr Screening for Pathogens in Air, Soil, Water, and Agricultural Produce
A sensitive, high-throughput, and cost-effective method for screening bacterial pathogens in the environment was developed. A variety of environmental samples, including aerosols, soil of various types (sand, sand/clay mix, and clay), wastewater, and vegetable surface (modeled by tomato), were conco...
| Main Authors: | , , , , |
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| Other Authors: | |
| Format: | Article |
| Language: | English |
| Published: |
Springer International Publishing,
2017-02-24T21:10:12Z.
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| Subjects: | |
| Online Access: | Get fulltext |
| Summary: | A sensitive, high-throughput, and cost-effective method for screening bacterial pathogens in the environment was developed. A variety of environmental samples, including aerosols, soil of various types (sand, sand/clay mix, and clay), wastewater, and vegetable surface (modeled by tomato), were concomitantly spiked with Salmonella enterica and/or Pseudomonas aeruginosa to determine recovery rates and limits of detection. The various matrices were first enriched with a general pre-enrichment broth in a dilution series and then enumerated by most probable number (MPN) estimation using quantitative PCR for rapid screening of amplicon presence. Soil and aerosols were then tested in non-spiked environmental samples, as these matrices are prone to large experimental variation. Limit of detection in the various soil types was 1-3 colony-forming units (CFU) g[superscript −1]; on vegetable surface, 5 CFU per tomato; in treated wastewater, 5 CFU L[superscript −1]; and in aerosols, >300 CFU mL[superscript −1]. Our method accurately identified S. enterica in non-spiked environmental soil samples within a day, while traditional methods took 4 to 5 days and required sorting through biochemically and morphologically similar species. Likewise, our method successfully identified P. aeruginosa in non-spiked aerosols generated by a domestic wastewater treatment system. The obtained results suggest that the developed method presents a broad approach for the rapid, efficient, and reliable detection of relatively low densities of pathogenic organisms in challenging environmental samples. United States-Israel Binational Agricultural Research and Development Fund (Grant No. CP-9033-09) MIT International Science and Technology Initiatives Kraft Foods Company |
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