Antibacterial and antiviral activities of stinging nettle (urtica dioica l.) Leaf extract on norovirus and campylobacter jejuni as foodborne pathogens

Experimental approach. The cytotoxic concentration of 50% (CC50) was measured by the linearity between UDE concentrations and cell viability. Antibacterial effects on C. jejuni were analyzed by the broth microdilution method with a spectrophotometer. The virucidal and antiviral activities of UDE were determined by the virus titration method on the host cell infectivity and expressed as the tissue cell infective dose of 50% using the method of Spearman–Karber.

Results and conclusions. The CC50 of UDE was determined on macrophage as the virus host cell. MIC and MBC of UDE were determined as 5 mg/ml and 20 mg/ml for both C. jejuni isolated from poultry meat and the standard strain. UDE inhibited MNV-1 on three pathways of host cell infectivity at approximately the same 50% inhibitory concentration (1.45-1.87 mg/ml). In conclusion, the present study tried to explain in detail the dose-dependent activity of Urtica dioica L. leaf extract on two important foodborne pathogens causing outbreaks worldwide. The results showed that it might be a safe and alternative food additive and supplement candidate at safe concentrations.