Submitted to: Journal Of Applied Bacteriology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: November 1, 1996
Publication Date: N/A
Interpretive Summary: A bacterium, Listeria monocytogenes, can cause illness and possibly death when eaten by humans consuming contaminated poultry products. Results from this study indicate that the growth of Listeria monocytogenes can be reduced by the products of another bacterium, Veillonella, that is normally found in the digestive tract of poultry. We observed that the Veillonella made two products, acetate and propionate. In addition, the growth of Listeria monocytogenes caused the acid content of the growth media to increase. The increased acid content in the growth media and increased amounts of the products made by Veillonella (i. e., acetate and propionate) resulted in the reduction in the growth of Listeria monocytogenes. These findings identify a specific bacterium found in poultry that can inhibit the growth of Listeria and will aid in the development of management strategies designed to reduce Listeria in poultry and thus reduce the potential for sickness in consumers of poultry products.
Veillonella cultures were grown on agar media supplemented with tartrate and examined for inhibitory effect on the growth of Listeria monocytogenes. Veillonella cultures grown on media supplemented with 0 or 50 mmol 1**-1 of tartrate did not inhibit the growth of L. monocytogenes; however, Veillonella grown on media supplemented with 100, 150, or 200 mmol 1**-1 of tartrate did inhibit the growth of L. monocytogenes. The inhibition of L. monocytogenes by the Veillonella was correlated with the increased production of acetate and propionate from tartrate by Veillonella and with the reduction of the media pH by L. monocytogenes.