Interactions and inhibition of pathogenic foodborne bacteria with individual dissociated organic acid species: A review

Authors: Beier, Ross

Submitted to: Journal of Food Chemistry & Nanotechnology
Publication Type: Review Article
Publication Acceptance Date: 2/15/2021
Publication Date: 2/18/2021
Citation: Beier, R.C. 2021. Interactions and inhibition of pathogenic foodborne bacteria with individual dissociated organic acid species: A review. Journal of Food Chemistry & Nanotechnology. 7(1):4-17. https://doi.org/10.17756/jfcn.2021-0106.
DOI: https://doi.org/10.17756/jfcn.2021-0106

Interpretive Summary: The World Health Organization in 2017 named 12 pathogenic bacteria that pose a great threat to human health. Estimates of foodborne illnesses provided in 2011 by the Centers for Disease Control and Prevention and a summary report on foodborne outbreaks in 2015 by the European Food Safety Authority and European Centre for Disease Prevention and Control associated the following pathogens with the threat to human health: Pseudomonas aeruginosa, Enterococcus faecium, Staphylococcus aureus, Campylobacter, Salmonella, Shiga toxin-producing Escherichia coli O157 (O157 STECs), and non-O157 STECs. Researchers have suggested that new strategies must be developed to control foodborne pathogens and the mechanism(s) of bacterial inhibition by organic acids must be identified. This review presents an overview of eight studies of major pathogens and their interactions with organic acids, and focuses on the following eight bacteria: C. jejuni, C. coli, Salmonella, E. coli O157:H7, non-O157 STECs, Ps. aeruginosa, vancomycin-resistant E. faecium (VRE), and S. aureus. In the studies reviewed, the pH at the points of bacterial inhibition were measured. The studies reviewed here clearly show that the dissociated organic acids are highly correlated with the inhibition of the eight pathogenic bacteria reviewed.

Technical Abstract: The World Health Organization in 2017 named 12 pathogenic bacteria that pose a great threat to human health. A summary report on zoonotic agents and foodborne outbreaks in 2015 by the European Food Safety Authority and European Centre for Disease Prevention and Control identified pathogenic bacteria, and estimates of foodborne illnesses in 2011 by the Centers for Disease Control and Prevention have associated the following pathogens with the threat to human health: Pseudomonas aeruginosa, Enterococcus faecium, Staphylococcus aureus, Campylobacter, Salmonella, Shiga toxin-producing Escherichia coli O157 (O157 STECs), and non-O157 STECs. Researchers have suggested that new strategies must be developed to control foodborne pathogens and the mechanism(s) of bacterial inhibition by organic acids (OAs) must be identified. This review presents an overview of eight studies of major pathogens and their interactions with OAs, and focuses on the following eight bacteria: C. jejuni, C. coli, Salmonella spp., E. coli O157:H7, non-O157 STECs, Ps. aeruginosa, vancomycin-resistant E. faecium (VRE), and S. aureus. In the studies reviewed the pH was measured at the molar MICs (MICMs), and the concentrations of undissociated and dissociated OAs were calculated at the MICMs using the Henderson-Hasselbalch equation. The inhibition of bacterial strains was not solely dependent on pH or on the concentration of undissociated OAs. These studies clearly show that a dissociated OA level of acetic, formic, propionic, citric, L-lactic, and butyric acids with dissociated acid levels of 21.83, 19.81, 18.18, 20.39, 22.23, and 22.56 mM representing a delta = 4.38 mM difference between different OAs will inhibit 100% of the strains studied from all eight bacterial species. However, when a bacterium utilizes an OA, the levels of that OA will necessarily be significantly increased to cause inhibition of the bacterium. This review has clearly shown that the dissociated OAs are highly correlated with the MICMs of the eight pathogenic bacteria reviewed here.