Sodium Chloride Does Not Ensure Microbiological Safety of Foods: Cases and Solutions

Kim, Nam Hee; Cho, Tae Jin; Rhee, Min Suk

doi:10.1016/bs.aambs.2017.05.001

Cited by 20 publications

(10 citation statements)

References 210 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In addition, Vibrio , a potentially unfavorable genus for food production, was relatively predominant. This result corresponds to a previous report indicating that salt-cured food can be contaminated with undesired halotolerant microbes ( Kim, Cho & Rhee, 2017 ). Because Vibrio is a halotolerant and facultative anaerobic genus, it is difficult to eliminate this genus by ambient salinity and anaerobic conditions.…”

Section: Discussionsupporting

confidence: 92%

The effects of vegetable pickling conditions on the dynamics of microbiota and metabolites

Sawada¹,

Koyano

Yamamoto

et al. 2021

PeerJ

View full text Add to dashboard Cite

Background Salting is a traditional procedure for producing pickled vegetables. Salting can be used as a pretreatment, for safe lactic acid fermentation and for salt stock preparation. This study aimed to provide valuable knowledge to improve pickle production by investigating the dynamics of microbiota and metabolites during the pretreatment and salt stock preparation processes, which have previously been overlooked. The differences in these process conditions would be expected to change the microbiota and consequently influence the content of metabolites in pickles. Methods Samples, collected from eight commercial pickle manufacturers in Japan, consisted of the initial raw materials, pickled vegetables and used brine. The microbiota were analyzed by 16S rRNA sequencing and the metabolites quantified by liquid chromatograph-mass spectrometry. Statistical analyses helped to identify any significant differences between samples from the initial raw materials, pretreatment process and salt stock preparation process groups. Results Under pretreatment conditions, aerobic and facultative anaerobic bacteria were predominant, including Vibrio, a potentially undesirable genus for pickle production. Under salt stock preparation conditions, the presence of halophilic bacteria, Halanaerobium, suggested their involvement in the increase in pyruvate derivatives such as branched-chain amino acids (BCAA). PICRUSt analysis indicated that the enhanced production of BCAA in salt stock was caused not by quantitative but by qualitative differences in the biosynthetic pathway of BCAA in the microbiota. Conclusion The differences in the microbiota between pretreatment and previously studied lactic acid fermentation processes emphasized the importance of anaerobic conditions and low pH under moderate salinity conditions for assuring safe pickle production. The results from the salt stock preparation process suggested that the Halanaerobium present may provide a key enzyme in the BCAA biosynthetic pathway which prefers NADH as a coenzyme. This feature can enhance BCAA production under anaerobic conditions where NADH is in excess. The effects shown in this study will be important for adjusting pickling conditions by changing the abundance of bacteria to improve the quality of pickled vegetables.

show abstract

Section: Discussionsupporting

confidence: 92%

The effects of vegetable pickling conditions on the dynamics of microbiota and metabolites

Sawada¹,

Koyano

Yamamoto

et al. 2021

PeerJ

View full text Add to dashboard Cite

show abstract

“…2), we identified Sa M1PDH as an indispensable stress-alleviating enzyme, which supports the idea of the halophilic nature of S. aureus strains (49). The pH and ROS stress responses were shown to be essential for pathogen acclimation under pathophysiological conditions in the host cell (50).…”

Section: Discussionsupporting

confidence: 81%

Targeting Mannitol Metabolism as an Alternative Antimicrobial Strategy Based on the Structure-Function Study of Mannitol-1-Phosphate Dehydrogenase in Staphylococcus aureus

Nguyen

Kim

et al. 2019

mBio

View full text Add to dashboard Cite

Mannitol-1-phosphate dehydrogenase (M1PDH) is a key enzyme in Staphylococcus aureus mannitol metabolism, but its roles in pathophysiological settings have not been established. We performed comprehensive structure-function analysis of M1PDH from S. aureus USA300, a strain of community-associated methicillin-resistant S. aureus, to evaluate its roles in cell viability and virulence under pathophysiological conditions. On the basis of our results, we propose M1PDH as a potential antibacterial target. In vitro cell viability assessment of ΔmtlD knockout and complemented strains confirmed that M1PDH is essential to endure pH, high-salt, and oxidative stress and thus that M1PDH is required for preventing osmotic burst by regulating pressure potential imposed by mannitol. The mouse infection model also verified that M1PDH is essential for bacterial survival during infection. To further support the use of M1PDH as an antibacterial target, we identified dihydrocelastrol (DHCL) as a competitive inhibitor of S. aureus M1PDH (SaM1PDH) and confirmed that DHCL effectively reduces bacterial cell viability during host infection. To explain physiological functions of SaM1PDH at the atomic level, the crystal structure of SaM1PDH was determined at 1.7-Å resolution. Structure-based mutation analyses and DHCL molecular docking to the SaM1PDH active site followed by functional assay identified key residues in the active site and provided the action mechanism of DHCL. Collectively, we propose SaM1PDH as a target for antibiotic development based on its physiological roles with the goals of expanding the repertory of antibiotic targets to fight antimicrobial resistance and providing essential knowledge for developing potent inhibitors of SaM1PDH based on structure-function studies. IMPORTANCE Due to the shortage of effective antibiotics against drug-resistant Staphylococcus aureus, new targets are urgently required to develop next-generation antibiotics. We investigated mannitol-1-phosphate dehydrogenase of S. aureus USA300 (SaM1PDH), a key enzyme regulating intracellular mannitol levels, and explored the possibility of using SaM1PDH as a target for developing antibiotic. Since mannitol is necessary for maintaining the cellular redox and osmotic potential, the homeostatic imbalance caused by treatment with a SaM1PDH inhibitor or knockout of the gene encoding SaM1PDH results in bacterial cell death through oxidative and/or mannitol-dependent cytolysis. We elucidated the molecular mechanism of SaM1PDH and the structural basis of substrate and inhibitor recognition by enzymatic and structural analyses of SaM1PDH. Our results strongly support the concept that targeting of SaM1PDH represents an alternative strategy for developing a new class of antibiotics that cause bacterial cell death not by blocking key cellular machinery but by inducing cytolysis and reducing stress tolerance through inhibition of the mannitol pathway.

show abstract

“…The synergistic effect of sodium chloride and essential oil containing carvacrol and thymol showed antimicrobial action on E. coli O157:H7 , L. monocytogenes , and S. aureus . A combined form of carvacrol/thymol (2.0 mM) with NaCl (≥3%) induced membrane disruption, and bacterial cells lost their ability to maintain osmotic balance and became completely inactivated (Kim et al, 2017 ; Mazarei & Rafati, 2019 ). Carvacrol combination with hydroxypropyl methylcellulose, tapioca starch, glycerol, and potassium sorbate showed significant microbial effects for Zygosaccharomyces bailii , Pseudomonas fluorescens , and Lactobacillus plantarum as compared to films only containing KS., L. plantarum , and P. fluorescens in comparison with films containing only KS (Alzate et al, 2017 ).…”

Section: Therapeutic Perspectivesmentioning

confidence: 99%

Therapeutic application of carvacrol: A comprehensive review

Imran¹,

Aslam

Alsagaby

et al. 2022

Food Science & Nutrition

View full text Add to dashboard Cite

Carvacrol is a major natural constituent and is significantly present as an essential oil in aromatic plants and is well known for its numerous biological activities. Therapeutic properties of carvacrol have been demonstrated as anti‐oxidant, anticancer, diabetes prevention, cardioprotective, anti‐obesity, hepatoprotective and reproductive role, antiaging, antimicrobial, and immunomodulatory properties. The carvacrol biosynthesis has been mediated through mevalonate pathway. Carvacrol has the anticancer ability against malignant cells via decreasing the expressions of matrix metalloprotease 2 and 9, inducing apoptosis, enhancing the expression of pro‐apoptotic proteins, disrupting mitochondrial membrane, suppressing extracellular signal‐regulated kinase 1/2 mitogen‐activated protein kinase signal transduction, and also decreasing the phosphoinositide 3‐kinase/protein kinase B. It also decreased the concentrations of alanine aminotransferase, alkaline phosphatase and aspartate aminotransferase, and gamma‐glutamyl transpeptidase as well as also restored liver function, insulin level, and plasma glucose level. Carvacrol also has been found to exert antimicrobial activity against Staphylococcus aureus, Pseudomonas aeruginosa, Coagulase‐negative staphylococcus, Salmonella spp., Enterococcus sp. Shigella, and Escherichia coli. The current review article summarizes the health‐promoting perspectives of carvacrol through various pathways.

show abstract

Sodium Chloride Does Not Ensure Microbiological Safety of Foods: Cases and Solutions

Cited by 20 publications

References 210 publications

The effects of vegetable pickling conditions on the dynamics of microbiota and metabolites

The effects of vegetable pickling conditions on the dynamics of microbiota and metabolites

Targeting Mannitol Metabolism as an Alternative Antimicrobial Strategy Based on the Structure-Function Study of Mannitol-1-Phosphate Dehydrogenase in Staphylococcus aureus

Therapeutic application of carvacrol: A comprehensive review

Contact Info

Product

Resources

About