Corrigendum to: Ingestion of organic acids and cinnamaldehyde improves tissue homeostasis of piglets exposed to enterotoxic Escherichia coli (ETEC)

This study was conducted to evaluate the abilities of five neutralizing agents, Dey-Engley (DE) neutralizing broth (single or double strength), morpholinepropanesulfonic acid (MOPS) buffer, phosphate-buffered saline (PBS), and sodium thiosulfate buffer, in mitigating the activities of acetic or lactic acid (2%) and an alkaline or acidic sanitizer (a manufacturer-recommended concentration) againt the cells of Shiga toxin–producing Escherichia coli (STEC; n = 9). To evaluate the possible toxicity of the neutralizing agents to the STEC cells, each STEC strain was exposed to each of the neutralizing agents at room temperature for 10 min. Neutralizing efficacy was evaluated by placing each STEC strain in a mixture of sanitizer and neutralizer under the same conditions. The neutralizing agents had no detectable toxic effect on the STEC strains. PBS was least effective for neutralizing the activity of selected organic acids and sanitizers. Single-strength DE and sodium thiosulfate neutralized the activity of both acetic and lactic acids. MOPS buffer neutralized the activity of acetic acid and lactic acid against six and five STEC strains, respectively. All neutralizing agents, except double-strength DE broth, had a limited neutralizing effect on the activity of the commercial sanitizers used in the study. The double-strength DE broth effectively neutralized the activity of the two commercial sanitizers with no detectable toxic effects on STEC cells.

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Identification and Probiotic Potency Screening of Cellulolytic Bacilli Isolated from Fecal Pellets and Gastrointestinal Tract of Nypha Worm (Namalycastis rhodochorde), West Kalimantan, Indonesia

Jurnal Biologi Indonesia ◽

10.47349/jbi/17022021/189 ◽

2021 ◽

Vol 17 (2) ◽

pp. 189-195

Author(s):

TR Setyawati ◽

AH Yanti ◽

R. Kurniatuhadi

Keyword(s):

Escherichia Coli ◽

Gastrointestinal Tract ◽

Organic Acids ◽

Acid Tolerance ◽

Distilled Water ◽

Bacterial Identification ◽

Bacterial Isolates ◽

Fecal Pellets ◽

West Kalimantan ◽

E Coli

The bacterial isolates NrLtF1, NrLtF4, NrLtF5, and NrLtG2 isolated from fecal pellets and gastrointestinal tract of nypha worms (Namalycastis rhodochorde) have cellulolytic, proteolytic activity and produce organic acids. The four isolates have the potency to be developed as probiotics in nypha worm cultivation feed. This study aims to determine the probiotics potency and identify the species of NrLtF1, NrLtF4, NrLtF5, and NrLtG2 isolate based on 16srDNA sequence. The probiotic potency was carried out by the acid tolerance assays on distilled water and 0.3% acid bile media, and the antimicrobial testing against Escherichia coli (MF exp21.12). Bacterial identification was carried out by sequencing of 16sDNA sequence based on GeneBank data. The results showed that the bacterial isolates of NrLtF1, NrLtF4, NrLtF5, and NrLtG2 were able to grow on 0.3% distilled water and acid bile media. However, only the NrLtF4 and NrLtF5 inhibited E. coli (MF exp21.12) with halo zones 30 mm and 18 mm, respectively. Blasting results of the 16srDNA sequences showed that the NrLtF1, NrLtF4, NrLtF5, and NrLtG2 were closely related to Bacillus wiedmannii, Brevibacterium sediminis, Bacillus proteolyticus, and Bacillus paramycoides. The nypha worm bacterial isolates have the potency to be developed as probiotics in nypha worm culture.

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Inactivation of Multi-Drug Resistant Non-Typhoidal Salmonella and Wild-Type Escherichia coli STEC Using Organic Acids: A Potential Alternative to the Food Industry

Pathogens ◽

10.3390/pathogens9100849 ◽

2020 ◽

Vol 9 (10) ◽

pp. 849

Author(s):

Vinicius Silva Castro ◽

Yhan da Silva Mutz ◽

Denes Kaic Alves Rosario ◽

Adelino Cunha-Neto ◽

Eduardo Eustáquio de Souza Figueiredo ◽

...

Keyword(s):

Escherichia Coli ◽

Acetic Acid ◽

Organic Acids ◽

Sodium Hypochlorite ◽

Bacterial Species ◽

Disk Diffusion ◽

Clinical Strains ◽

Linear Pattern ◽

E Coli ◽

Log Reduction

Salmonella and Escherichia coli are the main bacterial species involved in food outbreaks worldwide. Recent reports showed that chemical sanitizers commonly used to control these pathogens could induce antibiotic resistance. Therefore, this study aimed to describe the efficiency of chemical sanitizers and organic acids when inactivating wild and clinical strains of Salmonella and E. coli, targeting a 4-log reduction. To achieve this goal, three methods were applied. (i) Disk-diffusion challenge for organic acids. (ii) Determination of MIC for two acids (acetic and lactic), as well as two sanitizers (quaternary compound and sodium hypochlorite). (iii) The development of inactivation models from the previously defined concentrations. In disk-diffusion, the results indicated that wild strains have higher resistance potential when compared to clinical strains. Regarding the models, quaternary ammonium and lactic acid showed a linear pattern of inactivation, while sodium hypochlorite had a linear pattern with tail dispersion, and acetic acid has Weibull dispersion to E. coli. The concentration to 4-log reduction differed from Salmonella and E. coli in acetic acid and sodium hypochlorite. The use of organic acids is an alternative method for antimicrobial control. Our study indicates the levels of organic acids and sanitizers to be used in the inactivation of emerging foodborne pathogens.

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Electrostatic Spray of Food-Grade Organic Acids and Plant Extract to Reduce Escherichia coli O157:H7 on Fresh-Cut Cantaloupe Cubes

Journal of Food Safety ◽

10.1111/jfs.12024 ◽

2013 ◽

Vol 33 (1) ◽

pp. 71-78 ◽

Cited By ~ 11

Author(s):

Leighanna M. Massey ◽

Navam S. Hettiarachchy ◽

Elizabeth M. Martin ◽

Steven C. Ricke

Keyword(s):

Escherichia Coli ◽

Organic Acids ◽

Plant Extract ◽

Escherichia Coli O157 ◽

Food Grade ◽

Fresh Cut ◽

Electrostatic Spray

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Proflavine binding and release by sensitive and resistant Bacillus subtilis

Canadian Journal of Microbiology ◽

10.1139/m70-166 ◽

1970 ◽

Vol 16 (10) ◽

pp. 973-981

Author(s):

Gy. Barabas ◽

B. M. Mehta ◽

D. J. Kushner

Keyword(s):

Escherichia Coli ◽

Bacillus Subtilis ◽

Organic Acids ◽

Resistant Strain ◽

Binding Capacity ◽

Sensitive Strain ◽

Growth Media ◽

Sodium Salts ◽

Salts Of Organic Acids ◽

Resistant Cells

Proflavine binding of a sensitive strain of Bacillus subtilis and of a resistant strain derived from it was compared. Proflavine was bound very rapidly and more was bound at 0 °C than at 37 °C. Boiling increased the proflavine-binding capacity at 37 °C of sensitive but not of resistant cells. The binding capacity of sensitive and resistant cells suspended in buffer was the same; this was also true in various growth media. If cells were able to grow in the presence of proflavine their proflavine content decreased.Bound proflavine was released when cells were treated with growth media or with the salts of growth media. Sodium salts of organic acids also caused a release. This effect seemed due to their Na+ content, and was somewhat higher for resistant than for sensitive cells. The mechanism of proflavine resistance in B. subtilis is probably different from that of Escherichia coli, which is thought to depend on an energy-driven release of bound proflavine.

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Control of the Biofilms Formed by Curli- and Cellulose-Expressing Shiga Toxin–Producing Escherichia coli Using Treatments with Organic Acids and Commercial Sanitizers

Journal of Food Protection ◽

10.4315/0362-028x.jfp-14-382 ◽

2015 ◽

Vol 78 (5) ◽

pp. 990-995 ◽

Cited By ~ 4

Author(s):

YOEN JU PARK ◽

JINRU CHEN

Keyword(s):

Escherichia Coli ◽

Stainless Steel ◽

Organic Acids ◽

Shiga Toxin ◽

Cell Contact ◽

Bacterial Cells ◽

Bacterial Surface ◽

Additional Information ◽

Steel Surfaces ◽

Biological Protection

Biofilms are a mixture of bacteria and extracellular products secreted by bacterial cells and are of great concern to the food industry because they offer physical, mechanical, and biological protection to bacterial cells. This study was conducted to quantify biofilms formed by different Shiga toxin–producing Escherichia coli (STEC) strains on polystyrene and stainless steel surfaces and to determine the effectiveness of sanitizing treatments in control of these biofilms. STEC producing various amounts of cellulose (n = 6) or curli (n = 6) were allowed to develop biofilms on polystyrene and stainless steel surfaces at 28°C for 7 days. The biofilms were treated with 2% acetic or lactic acid and manufacturer-recommended concentrations of acidic or alkaline sanitizers, and residual biofilms were quantified. Treatments with the acidic and alkaline sanitizers were more effective than those with the organic acids for removing the biofilms. Compared with their counterparts, cells expressing a greater amount of cellulose or curli formed more biofilm mass and had greater residual mass after sanitizing treatments on polystyrene than on stainless steel. Research suggests that the organic acids and sanitizers used in the present study differed in their ability to control biofilms. Bacterial surface components and cell contact surfaces can influence both biofilm formation and the efficacy of sanitizing treatments. These results provide additional information on control of biofilms formed by STEC.

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Transcriptomic Analysis of Escherichia coli O157:H7 and K-12 Cultures Exposed to Inorganic and Organic Acids in Stationary Phase Reveals Acidulant- and Strain-Specific Acid Tolerance Responses

Applied and Environmental Microbiology ◽

10.1128/aem.02392-09 ◽

2010 ◽

Vol 76 (19) ◽

pp. 6514-6528 ◽

Cited By ~ 55

Author(s):

Thea King ◽

Sacha Lucchini ◽

Jay C. D. Hinton ◽

Kari Gobius

Keyword(s):

Escherichia Coli ◽

Hydrochloric Acid ◽

Organic Acids ◽

Stationary Phase ◽

Molecular Mechanisms ◽

Microbial Inactivation ◽

Specific Response ◽

Transcriptomic Response ◽

E Coli ◽

K 12

ABSTRACT The food-borne pathogen Escherichia coli O157:H7 is commonly exposed to organic acid in processed and preserved foods, allowing adaptation and the development of tolerance to pH levels otherwise lethal. Since little is known about the molecular basis of adaptation of E. coli to organic acids, we studied K-12 MG1655 and O157:H7 Sakai during exposure to acetic, lactic, and hydrochloric acid at pH 5.5. This is the first analysis of the pH-dependent transcriptomic response of stationary-phase E. coli. Thirty-four genes and three intergenic regions were upregulated by both strains during exposure to all acids. This universal acid response included genes involved in oxidative, envelope, and cold stress resistance and iron and manganese uptake, as well as 10 genes of unknown function. Acidulant- and strain-specific responses were also revealed. The acidulant-specific response reflects differences in the modes of microbial inactivation, even between weak organic acids. The two strains exhibited similar responses to lactic and hydrochloric acid, while the response to acetic acid was distinct. Acidulant-dependent differences between the strains involved induction of genes involved in the heat shock response, osmoregulation, inorganic ion and nucleotide transport and metabolism, translation, and energy production. E. coli O157:H7-specific acid-inducible genes were identified, suggesting that the enterohemorrhagic E. coli strain possesses additional molecular mechanisms contributing to acid resistance that are absent in K-12. While E. coli K-12 was most resistant to lactic and hydrochloric acid, O157:H7 may have a greater ability to survive in more complex acidic environments, such as those encountered in the host and during food processing.

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