Using novel pre-harvest, resistance-conferring treatments to prevent foodborne pathogenic outbreaks in produce

Abstract - Ascribe Bioscience is developing a novel technology to prevent foodborne outbreaks and recalls caused by the consumption of fresh or minimally processed fruits and vegetables. Product recalls and outbreaks of foodborne illness associated with fresh produce are on the rise in the U.S. In 2015, two outbreaks of E.

coli O26 linked with fresh tomato salsa were responsible for 60 illnesses and 22 hospitalizations. In 2011, a multistate outbreak of Listeria linked to whole cantaloupes led to 143 hospitalizations and 33 deaths. Another cantaloupe-linked outbreak caused by Salmonella caused 261 cases across 24 states, with 94 hospitalizations

and 3 deaths. Since most fresh produce is consumed raw, with no processing step to eliminate or minimize pathogens, they remain a major source of contamination. Fresh produce can become contaminated with pathogens at any steps of food production—during harvesting, or at various post-harvest stages including

processing, transport, and storage. Continued increase of farm-to-fork distances further amplifies the risk of product contamination with pathogens, creating a significant—but largely preventable—public health burden. Chlorine-based treatments have commonly being used to disinfect fresh and minimally processed fruits and

vegetables, but they have limited effectiveness due to inaccessibility to internal tissues where pathogens can flourish unaffected. To prevents outbreaks of foodborne associated with fresh produce, Ascribe is developing a treatment technology based on a natural molecule that activates plant defenses that persists over time, offering

reliable, long-term protection against a broad range of bacterial pathogens. Ascribe’s proposed treatment technology has the potential to dramatically improve the safety of raw produce by addressing both external and internal bacterial contamination. In response to seed, foliar spray, or root-drench application, plants deploy

an array of defense responses, which result in enhanced resistance against a broad spectrum of agriculturally important plant pathogens. In this project, Ascribe will establish the feasibility of the technology for the prevention of recalls and outbreaks related to human consumption of fresh or minimally processed fruits and vegetables.

The specific aims of this Phase I project are 1) Develop formulations for produce designed for application by soil drench and spraying, and determine their effects on germination, growth, and quality; 2) Test the efficacy of these formulations against human enteric pathogens Salmonella enterica in tomato and Listeria monocytogenes

in broccoli; 3) Test the effect of these treatments on the shelf life of tomato and broccoli. These aims will position Ascribe to further develop this technology in Phase II, in which Ascribe will refine the formulations, test efficacy against additional pathogens, expand to other types of fruits and vegetables, and perform toxicology studies to

support regulatory approval. If successful, Ascribe’s proposed technology will dramatically increase the safety of consuming fresh produce. The technology also has the potential to increase the shelf-life of fresh, cut, or minimally processed fruits and vegetables, increasing their accessibility to consumers.