@article{isonhood_drake_jaykus_2006, title={Upstream sample processing facilitates PCR detection of Listeria monocytogenes in mayonnaise-based ready-to-eat (RTE) salads}, volume={23}, ISSN={["1095-9998"]}, DOI={10.1016/j.fm.2005.09.004}, abstractNote={Sample pretreatment to reduce volume and concentrate cells of the target organism(s) prior to molecular detection offers a useful supplement or alternative to cultural enrichment. The purpose of this study was to develop an upstream processing method to facilitate the detection of Listeria monocytogenes in ready-to-eat (RTE) salads by PCR. Potato salad, a model RTE commodity, was seeded with L. monocytogenes and processed by two alternative upstream sample processing methods (designated one-step and two-step centrifugation), followed by DNA extraction, PCR amplification, and Southern hybridization. The two-step method resulted in 1000-fold improvements in the PCR detection limit, from 106 Cfu/g (no sample processing) to 103 Cfu/g. The two-step method was applied for upstream sample processing of four representative deli salad items artificially inoculated with L. monocytogenes at levels ranging from 101–106 Cfu/g. Following DNA extraction, PCR amplification, and Southern hybridization, detection was achieved at input levels of 105 Cfu/g for chicken salad, 104 Cfu/g for macaroni salad, and 103 Cfu/g for potato and seafood salads. The two-step method reported here facilitates the production of a final sample concentrate of reduced volume and improved purity which was compatible with PCR amplification. This approach offers further progress in our efforts to reduce or eliminate cultural enrichment in an effort to speed time to results when applying molecular methods to the detection of pathogens in foods.}, number={6}, journal={FOOD MICROBIOLOGY}, author={Isonhood, Jamie and Drake, MaryAnne and Jaykus, Lee-Ann}, year={2006}, month={Sep}, pages={584–590} }
 @article{campbell_bang_isonhood_gerard_drake_2004, title={Effects of salt, acid, and MSG on cold storage survival and subsequent acid tolerance of Escherichia coli O157 : H7}, volume={21}, ISSN={["1095-9998"]}, DOI={10.1016/j.fm.2004.02.004}, abstractNote={The combined effects of salt, monosodium glutamate (MSG), and pH on cold storage survival and subsequent acid tolerance of Escherichia coli O157:H7 were determined. Cold storage survival was evaluated in tryptic soy broth (TSB) with combinations of pH (7.2, 5.0, or 4.0), MSG (0, 0.5, 1%) and salt (0, 2, 4%). Survival through 21 d at 5°C and acid tolerance in simulated gastric fluid were evaluated weekly. In separate experiments, strains were tested individually for the effect of growth in the presence of MSG on subsequent acid resistance and for the ability of MSG to impact growth under acid conditions. The impact of salt on cold storage survival was greater at pH 4.0 and 7.0 compared to pH 5.0. MSG did not enhance cold storage survival. The presence of MSG alone enhanced acid tolerance following cold storage at pH 5.0 and 7.2 compared to control cells. At pH 4.0, MSG alone enhanced acid tolerance compared to control cells following 21 days cold storage. Overnight growth in TSB containing MSG did not affect subsequent acid tolerance in acidified TSB (pH 2.0). The presence of MSG in TSB (37°C) did not enable growth at lower pH.}, number={6}, journal={FOOD MICROBIOLOGY}, author={Campbell, J and Bang, W and Isonhood, J and Gerard, PD and Drake, MA}, year={2004}, month={Dec}, pages={727–735} }
 @misc{isonhood_drake_2002, title={Aeromonas species in foods}, volume={65}, ISSN={["1944-9097"]}, DOI={10.4315/0362-028X-65.3.575}, abstractNote={Aeromonas species have been recognized as potential or emerging foodborne pathogens for more than 20 years. Aeromonads are estuarine bacteria and are ubiquitous in fresh water, fish and shellfish, meats, and fresh vegetables. Actual sourced foodborne outbreaks are few, but epidemiological evidence suggests that the bacterium can cause self-limiting diarrhea, with children being the most susceptible population. Most aeromonads are psychrotrophic and can grow in foods during cold storage. Aeromonads are not resistant to food processing regimes and are readily killed by heat treatment. A host of virulence factors are present, but the exact role of each in human disease has not been fully elucidated.}, number={3}, journal={JOURNAL OF FOOD PROTECTION}, author={Isonhood, JH and Drake, M}, year={2002}, month={Mar}, pages={575–582} }
 @article{isonhood_gerard_leenanon_drake_2002, title={Stress response of Aeromonas hydrophila following environmental challenges}, volume={19}, DOI={10.1006/yfmic.500}, number={4}, journal={Food Microbiology}, author={Isonhood, J. H. and Gerard, P. and Leenanon, B. and Drake, M.}, year={2002}, pages={285–293} }