Anti-bacterial activity of Lactobacillus plantarum strain SK1 against Listeria monocytogenes is due to lactic acid production.
OBJECTIVE
The aim of this research was to investigate the potential of Lactobacillus plantarum strain SK1 for use as a biological control agent against Listeria monocytogenes and determine its mechanism of anti-listerial activity.


RESULTS
Co-growth of Lact. plantarum SK1 and L. monocytogenes UMCC98 in MRS broth showed that anti-listerial activity of Lact. plantarum SK1 occurred during late log/early stationary phase of growth. This coincided with a reduction in broth pH to 4.26. Evidence obtained from the analysis of cell-free culture filtrates of strain SK1 grown in MRS broth using thin-layer chromatography and growth of L. monocytogenes in pH-adjusted culture filtrates suggested that the anti-listerial activity was due to lactic acid production alone. Trials of Lact. plantarum SK1 on radishes stored at 5 degrees C showed that it had statistically significant (P < 0.05) anti-listerial activity.


CONCLUSIONS
The anti-listerial activity of Lact. plantarum SK1 was due to lactic acid production alone. A small-scale trial on radishes stored at 5 degrees C showed it to have significant anti-listerial activity in planta.


CONCLUSIONS
This organism has potential as a biological control agent for L. monocytogenes.
Wilson
A R
AR
School of Biological Sciences, University of Manchester, Manchester, UK.
Sigee
D
D
Epton
H A S
HA
D000898:Antibiosis / Q000502:physiology*; D001431:Bacteriological Techniques; D002855:Chromatography, Thin Layer; D005516:Food Microbiology; D005524:Food Technology; D006801:Humans; D006863:Hydrogen-Ion Concentration; D019344:Lactic Acid / Q000378:metabolism*; D007778:Lactobacillus / Q000502:physiology*; D008089:Listeria monocytogenes; D008088:Listeriosis / Q000382:microbiology / Q000517:prevention & control; D013696:Temperature; D014675:Vegetables
D019344:Lactic Acid