Olive leaf extract inhibits growth and biofilm formation in L. monocytogenes

Olive extract has been used as a traditional herbal supplement since it contains polyphenolic compounds with a wide range of beneficial properties ranging from promoting increased energy and healthy blood pressure, supporting the cardiovascular system and the immune system. In addition to the beneficial effects, olive extract also has antimicrobial effects. The aim of this work was to investigate the antimicrobial effect of olive extract against Listeria monocytogenes, which is a major foodborne pathogen. Our results demonstrated that olive extract inhibited the growth of Listeria monocytogenes. The effects of olive extract against biofilm formation of L. monocytogenes were measured using a crystal violet assay. Our results showed that the olive extract inhibited biofilm formation and reduced the swimming motility of L. monocytogenes. Since biofilm formation is a serious problem for the food industry, olive extract, as a natural product, has the potential to be used as a food additive to control L. monocytogenes in food.