Recent and emerging innovations inSalmonelladetection: a food and environmental perspective

Abstract

Summary Salmonella is a diverse genus of Gram‐negative bacilli and a major foodborne pathogen responsible for more than a million illnesses annually in the United States alone. Rapid, reliable detection and identification of this pathogen in food and environmental sources is key to safeguarding the food supply. Traditional microbiological culture techniques have been the ‘gold standard’ for State and Federal regulators. Unfortunately, the time to result is too long to effectively monitor foodstuffs, especially those with very short shelf lives. Advances in traditional microbiology and molecular biology over the past 25 years have greatly improved the speed at which this pathogen is detected. Nonetheless, food and environmental samples possess a distinctive set of challenges for these newer, more rapid methodologies. Furthermore, more detailed identification and subtyping strategies still rely heavily on the availability of a pure isolate. However, major shifts in DNA sequencing technologies are meeting this challenge by advancing the detection, identification and subtyping of Salmonella towards a culture‐independent diagnostic framework. This review will focus on current approaches and state‐of‐the‐art next‐generation advances in the detection, identification and subtyping of Salmonella from food and environmental sources.

Early Recovery of Salmonella from Food Using a 6-Hour Non-selective Pre-enrichment and Reformulation of Tetrathionate Broth

“…The increasing use of rapid molecular methods such as qPCR and PCR for Salmonella detection have been highlighted in recent reviews (Park et al, 2014; Bell et al, 2016). qPCR assays require 10 2 Salmonella /reaction for a positive result and as little as 30 CFU of Salmonella are need for consistent detection with endpoint PCR (Park et al, 2014; Bell et al, 2016).…”

“…qPCR assays require 10 2 Salmonella /reaction for a positive result and as little as 30 CFU of Salmonella are need for consistent detection with endpoint PCR (Park et al, 2014; Bell et al, 2016). There is a consensus that a 6-h to 24-h pre-enrichment step is required for both of these methods to decrease the negative impacts on PCR and qPCR chemistry inherent to some types of food.…”

“…There is a consensus that a 6-h to 24-h pre-enrichment step is required for both of these methods to decrease the negative impacts on PCR and qPCR chemistry inherent to some types of food. Additional problems due to variations in competitive bacteria and inhibition due to the pre-enrichment broth itself were also noted (Park et al, 2014; Bell et al, 2016). Incorporating a 6-h selective TT B enrichment simultaneous to sample preparation for qPCR and PCR would be seamless for laboratories performing these assays, and would significantly increase the overall recovery rate of Salmonella .…”

Ultrasensitive Detection of Salmonella and Listeria monocytogenes by Small‐Molecule Chemiluminescence Probes

“…Every year, Salmonella is estimated to cause circa one million foodborne illnesses in the US,w ith 19 000 hospitalizations and 380 deaths. [11][12][13] As these molecular methods detect DNAorcell surface antigens (genotypic), ac onfirmatory test to show bacterial viability (phenotypic) is needed before taking action. [6] Detection of Salmonella and L. monocytogenes from food samples is currently performed by applying ISO-certified reference methods (ISO 6579 and ISO 11290, respectively).…”

Recent and the Latest Developments in Rapid and Efficient Detection of Salmonella in Food and Water

“…Sometimes, a secondary selective enrichment may yield better isolation results for some food samples [44]. However, the drawbacks with enrichment include intensive labor and long incubation time; and some food samples such as fresh produce and spices, may be difficult to grow due to the high numbers of indigenous microbiota and the presence of antimicrobials found within the food commodity [21,22,[46][47][48].…”