Assessing the growth of <i>Escherichia coli</i>
 O157:H7 and <i>Salmonella</i>
 in spinach, lettuce, parsley and chard extracts at different storage temperatures

Posada-Izquierdo, Guiomar Denisse; Rosal, Susana del; Valero, Antonio; Zurera, G.; Sant’Ana, Anderson S.; Alvarenga, Verônica O.; Pérez‐Rodríguez, Fernando

doi:10.1111/jam.13122

Cited by 15 publications

(11 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Previous research has indicated storage of vegetables at ambient conditions allowed for rapid pathogen growth (Hoelzer et al, 2012;Posada-Izquierdo et al, 2016;Mishra et al, 2017). As compared to results from 15°C-stored samples, UG and GPNs treatments yielded non-detectable numbers of E. coli O157:H7.…”

Section: Experimental Replication and Data Analysismentioning

confidence: 80%

“…Recent research describing the growth of both E. coli O157:H7 and Salmonella on spinach indicated increased growth rates of both organisms on the produce commodity when transitioned from refrigeration (5°C) to elevated/abusive storage temperatures, with lag phases of at least 10 h when ambient temperature was ≤21°C (Mishra et al, 2017). Research conducted on presterilized spinach extract indicated similar trends, with more rapid growth occurring when spinach was held at 16 or 20°C versus 8 or 10°C (Posada-Izquierdo et al, 2016). The FDA recommends the preservation of refrigeration conditions for storage of fresh produce during postharvest handling to prevent/slow growth of microbial pathogens (FDA, 2009(FDA, , 2013.…”

Section: Experimental Replication and Data Analysismentioning

confidence: 95%

See 1 more Smart Citation

Geraniol-Loaded Polymeric Nanoparticles Inhibit Enteric Pathogens on Spinach during Posttreatment Refrigerated and Temperature Abuse Storage

Perez-Lewis

Yegin

Cisneros‐Zevallos

et al. 2018

Front. Sustain. Food Syst.

View full text Add to dashboard Cite

Section: Experimental Replication and Data Analysismentioning

confidence: 80%

Section: Experimental Replication and Data Analysismentioning

confidence: 95%

Geraniol-Loaded Polymeric Nanoparticles Inhibit Enteric Pathogens on Spinach during Posttreatment Refrigerated and Temperature Abuse Storage

Perez-Lewis

Yegin

Cisneros‐Zevallos

et al. 2018

Front. Sustain. Food Syst.

View full text Add to dashboard Cite

“…Similar results were also seen with the other leaf juices (data not shown), all of which produced similar growth enhancement at 2%, which we then adopted as our standard salad juice addition concentration. A recent study by Posada-Izquierdo et al (27) also examined the growth kinetics of Salmonella in leafy salad extracts (chard, iceberg lettuce, parsley, and spinach). Those authors used much higher levels (33.3% [vol/vol]) of leaf juice in their growth analyses and found growth rates lower than those that we report here.…”

Section: Resultsmentioning

confidence: 99%

Salad Leaf Juices Enhance Salmonella Growth, Colonization of Fresh Produce, and Virulence

Koukkidis

Haigh

Allcock

et al. 2017

Appl Environ Microbiol

View full text Add to dashboard Cite

We show in this report that traces of juices released from salad leaves as they become damaged can significantly enhance colonization of salad leaves by Salmonella enterica. Salad juices in water increased Salmonella growth by 110% over the level seen with the unsupplemented control and in host-like serum-based media by more than 2,400-fold over control levels. In serum-based media, salad juices induced growth of Salmonella via provision of Fe from transferrin, and siderophore production was found to be integral to the growth induction process. Other aspects relevant to salad leaf colonization and retention were enhanced, such as motility and biofilm formation, which were increased over control levels by >220% and 250%, respectively; direct attachment to salad leaves increased by >350% when a salad leaf juice was present. In terms of growth and biofilm formation, the endogenous salad leaf microbiota was largely unresponsive to leaf juice, suggesting that Salmonella gains a marked growth advantage from fluids released by salad leaf damage. Salad leaf juices also enhanced pathogen attachment to the salad bag plastic. Over 5 days of refrigeration (a typical storage time for bagged salad leaves), even traces of juice within the salad bag fluids increased Salmonella growth in water by up to 280-fold over control cultures, as well as enhancing salad bag colonization, which could be an unappreciated factor in retention of pathogens in fresh produce. Collectively, the study data show that exposure to salad leaf juice may contribute to the persistence of Salmonella on salad leaves and strongly emphasize the importance of ensuring the microbiological safety of fresh produce.IMPORTANCE Salad leaves are an important part of a healthy diet but have been associated in recent years with a growing risk of food poisoning from bacterial pathogens such as Salmonella enterica. Although this is considered a significant public health problem, very little is known about the behavior of Salmonella in the actual salad bag. We show that juices released from the cut ends of the salad leaves enabled the Salmonella cells to grow in water, even when it was refrigerated. Salad juice exposure also helped the Salmonella cells to attach to the salad leaves so strongly that washing could not remove them. Collectively, the results presented in this report show that exposure to even traces of salad leaf juice may contribute to the persistence of Salmonella on salad leaves as well as priming it for establishing an infection in the consumer.

show abstract

“…from cut surfaces. A number of studies show growth of food-borne bacteria on plant extracts during the production process (35, 55, 56) and growth potential for E. coli O157:H7 has been evaluated in water (70). Here, maximum growth rates in plant extracts were strongly influenced by the plant tissue type and species, as well as the E. coli isolate tested and overlaid by temperature-dependent effects.…”

Section: Discussionmentioning

confidence: 99%

Relating growth potential and biofilm formation of ShigatoxigenicEscherichia colitoin plantacolonisation and the metabolome of ready-to-eat crops

Merget

Forbes

Brennan

et al. 2019

Preprint

View full text Add to dashboard Cite

/ 250 words)1 Contamination of fresh produce with pathogenic Escherichia coli, including Shigatoxigenic E. 2 coli (STEC), represents a serious risk to human health. Colonisation is governed by multiple 3 bacterial and plant factors that can impact on the probability and suitability of bacterial growth. 4 Thus, we aimed to determine whether the growth potential of STEC for plants associated with 5 foodborne outbreaks (two leafy vegetables and two sprouted seed species), is predictive for 6 colonisation of living plants as assessed from growth kinetics and biofilm formation in plant 7 extracts. Fitness of STEC was compared to environmental E. coli, at temperatures relevant to 8 plant growth. Growth kinetics in plant extracts varied in a plant-dependent and isolate-9 dependent manner for all isolates, with spinach leaf lysates supporting the fastest rates of 10 growth. Spinach extracts also supported the highest levels of biofilm formation. Saccharides 11 were identified as the major driver of bacterial growth, although no single metabolite could be 12 correlated with growth kinetics. The highest level of in planta colonisation occurred on alfalfa 13 sprouts, though internalisation was 10-times more prevalent in the leafy vegetables than in 14 sprouted seeds. Marked differences in in planta growth meant that growth potential could only 15 be inferred for STEC for sprouted seeds. In contrast, biofilm formation in extracts related to 16 spinach colonisation. Overall, the capacity of E. coli to colonise, grow and internalise within 17 plants or plant-derived matrices were influenced by the isolate type, plant species, plant tissue 18 type and temperature, complicating any straight-forward relationship between in vitro and in 19 planta behaviours. 20 3 Importance (149 / 150 word) 21 Fresh produce is an important vehicle for STEC transmission and experimental evidence 22shows that STEC can colonise plants as secondary hosts, but differences in the capacity to 23 colonise occur between different plant species and tissues. Therefore, an understanding of the 24 impact of these plant factors have on the ability of STEC to grow and establish is required for 25 food safety considerations and risk assessment. Here, we determined whether growth and the 26 ability of STEC to form biofilms in plants extracts could be related to specific plant metabolites 27 or could predict the ability of the bacteria to colonise living plants. Growth rates for sprouted 28 seeds (alfalfa and fenugreek) exhibited a positive relationship between plant extracts and living 29 plants, but not for leafy vegetables (lettuce and spinach). Therefore, the detailed variations at 30 the level of the bacterial isolate, plant species and tissue type all need to be considered in risk 31 assessment. 32 33 34Contamination of fresh produce from Shigatoxigenic Escherichia coli (STEC) presents a 35 serious hazard as a cause of food-borne illnesses, diarrhoea and enterohemorrhagic disease. 36Fresh produce is a major vehicle of transmission of STEC, with foods of...

show abstract

Assessing the growth of Escherichia coli O157:H7 and Salmonella in spinach, lettuce, parsley and chard extracts at different storage temperatures

Abstract: Finally, these results can be used as basis to establish risk rankings of pathogens and leafy vegetable matrices with relation to their potential growth.

Cited by 15 publications

References 35 publications

Geraniol-Loaded Polymeric Nanoparticles Inhibit Enteric Pathogens on Spinach during Posttreatment Refrigerated and Temperature Abuse Storage

Geraniol-Loaded Polymeric Nanoparticles Inhibit Enteric Pathogens on Spinach during Posttreatment Refrigerated and Temperature Abuse Storage

Salad Leaf Juices Enhance Salmonella Growth, Colonization of Fresh Produce, and Virulence

Relating growth potential and biofilm formation of ShigatoxigenicEscherichia colitoin plantacolonisation and the metabolome of ready-to-eat crops

Contact Info

Product

Resources

About