Performing Department
(N/A)
Non Technical Summary
Salmonella is a bacterial pathogen that causes >1.4 million cases of foodborne illness every year in the US, making it the most common cause of hospitalization and death due to a foodborne illness in the US. The USDA recently proposed legislation that would make Salmonella present in not-ready-to-eat stuffed breaded chicken products an adulterant. Current rapid detection methods require lab personnel to incubate the food product to allow growth of the target pathogen to higher levels so that it can be more easily detected. One of the major challenges with these rapid methods, is that this incubation takes 18-24 hours. We propose using a novel double-stage filter to rapidly filter out and collect bacteria from a food, thereby negating the need for an enrichment incubation step. To achieve this, we will engineer a stirred cell device to be anti-fouling to enable it to repel food particles; in stage two, we will pass the liquid food through a membrane that has pores that can collect the target bacteria, followed by direct extraction of DNA from bacterial cells collected by the membrane. Overall, this will allow food manufacturers to more rapidly and accurately screen their food products for the presence of foodborne pathogens, such as Salmonella to ensure the safety of their food product.
Animal Health Component
50%
Research Effort Categories
Basic
50%
Applied
50%
Developmental
(N/A)
Goals / Objectives
The overall goal of this project is to develop a filter-assisted device to enable accurate and sensitive detection of foodborne pathogens in food matrices without the need for an enrichment step. To achieve this goal, this project will accomplish the following objectives:Obj. I:Develop debris repelling membranes that through all-dry surface modification can enable flow-through of bacteria while excluding food debrisObj. II: Establish procedures for DNA extraction for Salmonella cells collected by the novel bacteria extraction membraneObj. III: Demonstrate the suitability of FAST to extract low levels of Salmonella from liquid and solid food matrices
Project Methods
We will develop a filter-based method that will remove and concentrate Salmonella from chicken broth and parts that can then be used as input in existing molecular detection methods. We propose using a tandem filtration setup. In the first filtration unit, a debris repelling membrane (DRM), featuring an antifouling zwitterionic coating, will be used to exclude food debris while allowing bacteria and smaller molecules to pass through. Subsequently, in the second filtration unit, the bacteria extraction membrane (BEM) will be used to retain bacteria while allowing potential PCR inhibitors from the food matrix to pass through, followed by extraction with TRIzol (phenol-chloroform) to extract high-quality DNA for input into existing molecular detection methods, such as the molecular detection system (MDS). Finally, we will use the optimized tandem filter system to assess the ability of the system to recover high, medium, and low levels of Salmonella inoculated into liquid (chicken broth) and solid (chicken breast) food matrices.It is critical to ensure that DRM does not retain bacteria or get clogged by debris in the food matrix. To this end, we will utilize an all-dry surface modification technology, known as initiated chemical vapor deposition (iCVD), to apply an antifouling zwitterionic polymer coating on commercial cellulose filters membranes (Co-PD Y. Cheng). This iCVD method enables excellent coating uniformity throughout the DRM, thus minimizing retention of bacteria and clogging of the membranes.