Addition of a surfactant to tryptic soy broth allows growth of a Lactic Acid Bacteria food antimicrobial, Escherichia coli O157:H7, and Salmonella enterica

• Published in: Letters in applied microbiology Vol. 54; no. 5; pp. 392 - 397
• Main Authors: Cálix‐Lara, T.F, Duong, T, Taylor, T.M
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.05.2012; Blackwell
• Subjects: antimicrobial(s); biocontrol; Biological and medical sciences; Culture Media - chemistry; Escherichia coli; Escherichia coli O157; Escherichia coli O157 - growth & development; Food Microbiology; food pathogens; food safety; foods; Fundamental and applied biological sciences. Psychology; Lactic Acid - metabolism; Lactic Acid Bacteria; Lactobacillaceae - growth & development; Microbiology; Polysorbates; Salmonella; Salmonella enterica; Salmonella enterica - growth & development; Salmonella enterica subsp. enterica; Salmonella; Lactic acid bacteria; Growth; Applied microbiology; Escherichia coli; Biological control; Foodstuff; Surfactant; Antimicrobial agent; Bacteria; biocontrol; Enterobacteriaceae; antimicrobial(s)
• ISSN: 0266-8254; 1472-765X
• DOI: 10.1111/j.1472-765X.2012.03218.x

Aims: This study aimed to determine the survival and growth of Escherichia coli O157:H7 and Salmonella enterica subsp. enterica in a medium supporting the growth of a Lactic Acid Bacteria (LAB) food antimicrobial culture. Methods and Results: Foodborne pathogens and LAB were cultured individually in tryptic soy broth (TSB), tryptic soy broth supplemented with one g l−1 Tween 80® (TSB‐T80), and de Man, Rogosa and Sharpe (MRS) broth. Growth of E. coli O157:H7 and Salmonella was similar in TSB and TSB‐T80 but was significantly less in MRS. Conversely, LAB growth was similar in MRS and TSB‐T80 but was significantly less in TSB. Conclusions: Supplementation of TSB with Tween 80® allows growth of LAB to levels similar to that observed with MRS but does not inhibit the growth of E. coli O157:H7 and Salmonella. We present the formulation of a medium useful in studies useful for evaluating competitive inhibition of foodborne pathogens by LAB in vitro. Significance and Impact of the Study: This study reports the utility of TSB‐T80 for the completion of in vitro competitive inhibition assays incorporating a Lactic Acid Bacteria food safety culture.