With the ever increasing population of Earth, it becomes crucial that the integrity of our food supply is maintained; outbreaks of food borne pathogens can affect people on a much grander scale if they this is not so. This research project set out to test whether it was possible to test for multiple pathogens in a single sample via a single assay, and if that was possible, what are the limits of detection (LOD) of this assay? The assay involved the use of magnetic micro-beads coupled with predesigned primers and biotinylated TaqMan probes that would report the presence of proteins specific to the pathogens in question. These proteins were the hlyA of Escherichia coli, hlyA of Listeria monocytogenes, and invA of Salmonella enteric serovar Typhimurium. Analysis on the Magpix by Luminex after real time PCR determined that simultaneous detection of three organisms present in a single sample revealed that it was possible. Median Fluorescense Intensity (MFI) readings concluded the simultaneous presence of all three pathogens in the single sample; electrophoresis gel testing confirmed these findings. This ongoing research will now focus on the detection in spiked apple juice samples and other food sources of these pathogens.


Sonam Sahni

Lab site

California State University, Fresno (CSU Fresno)

Funding Acknowledgement

This material is based upon work supported by the S.D. Bechtel, Jr. Foundation and by the National Science Foundation under Grant No. 0952013. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the S.D. Bechtel, Jr. Foundation or the National Science Foundation. This project has also been made possible with support of the National Marine Sanctuary Foundation. The STAR program is administered by the Cal Poly Center for Excellence in Science and Mathematics Education (CESaME) on behalf of the California State University (CSU).



URL: https://digitalcommons.calpoly.edu/star/219


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