Natural-flagella-templated Au nanowires and their neo-function as antimicrobial adjuvants

A simple extraction and purification of bacterial flagella was developed, with the concentration of 83.54 mg/ml. Au nanowires were synthesized using bacterial flagella as templates with uniform aspect ratio homogeneous along the whole Au nanowires more than 60. The nanowires were scarcely clustered as straight as nanorods with no fold-tendency under transmission electron microscopy (TEM). Olive leaf extract has been shown to inhibit the growth of Listeria monocytogenes, an important foodborne pathogen. Verbascoside and Oleuropein are two major components in olive leaf extract. The synthesized Au nanowires were highly active at the concentration of 128μg/ml for electrocatalytic inhibition of Verbascoside, Oleuropein and Olive leaf extract towards L. monocytogenes F2365 which significantly reduced the Minimal Inhibitory Concentration (MIC) concentrations compared with no addition of Au nanowires. Results from Ames assays indicate that synthesized Au nanowires had no mutagenic activities at the above catalytic concentration. The AU nanowires we developed have the potential to be used as anti-microbial food packaging materials to enhance food safety.