|SUO, YUJUAN - Shanghai Academy Of Agricultural Sciences|
Submitted to: ACS Symposium Series
Publication Type: Book / Chapter
Publication Acceptance Date: 7/22/2018
Publication Date: 9/4/2018
Citation: Liu, Y., Mckeever, L., Suo, Y., Jin, Z.T., Malik, N.S. 2018. Antimicrobial activities of olive leaf extract and its potential use in food industry. ACS Symposium Series. In: Fan, X., Ngo, H., and Wu, C.Natural and Bio-Based Antimicrobials for Food. 119-132.. https://org/doi/abs/10.1021/bk-2018-1287.ch006.
Technical Abstract: Listeria monocytogenes is a foodborne pathogen that can cause serious illnesses with high mortality rates (~20%). Olive leaf extract (OLE) has been reported to inhibit the growth of several foodborne pathogens. In this study, growth inhibition assays were utilized to determine the minimal inhibitory concentrations (MICs) of OLE against not only L. monocytogenes F2365, but also several other foodborne pathogens. Commercial oleuropein and verbascoside (two of the major phenolic compounds present in OLE) were also tested for growth inhibitory properties against L. monocytogenes. The MIC of OLE against L. monocytogenes was found to be 62.5 mg/ml. The MIC of pure verbascoside was determined to be 6.25 mg/ml, while the MIC of pure oleuropein was determined to be 25 mg/ml. In addition to growth inhibition assays, both biofilm and motility assays were conducted with L. monocytogenes F2365, with different concentrations of OLE. At an OLE concentration of 7.8 mg/ml, both motility and biofilm formation of L. monocytogenes were decreased. Furthermore, an antimicrobial film containing 6% of OLE was able to inhibit the growth of L. innocua, indicating that OLE can be considered as a food packing material. Our results indicate that OLE has the potential to be used in the food industry to inhibit the growth of foodborne pathogens either in foods or on food processing equipment.