Analyses of Spatiotemporal Variation of Antioxidative Activity in Common Mistletoe (Viscum Album l.) Accompanied by Antibacterial Activity of Green Synthesized Silver Nanoparticles

Common mistletoe (Viscum album L.) is a semi-parasitic plant that grows on various woody species and is known for its anti-inflammatory, antibacterial, and antitumor properties. It is used in the treatment of various diseases and conditions. The antioxidant properties of mistletoe depend on the type of the host, region, and sampling time. In this study, we investigated the impact of location and sampling time on the content of bioactive compounds content and antioxidative activity in a freshly harvested mistletoe leaves, twigs, and commercial tea mixtures. Additionally, we present a suitable green synthesis procedure for silver nanoparticles (AgNPs) using mistletoe extract, followed by antimicrobial activity analyses. Samples harvested in October exhibited significantly higher content of bioactive compounds compared to those collected in February. Fresh samples and commercial tea mixtures showed no significant difference in measured parameters, except for the samples in Istria, Petrijevci, and Aljmaš. AgNPs were successfully synthesized using mistletoe methanolic extract with a UV–vis absorption peak at 439 nm. The crystallite diameter of the AgNPs, as determined by PXRD averaged 21 nm. The AgNPs synthesized using mistletoe methanolic extract demonstrated potent antimicrobial activity against the human pathogens Escherichia coli (E. coli), Pseudomonas aeruginosa (P. aeruginosa), Bacillus subtilis (B. subtilis), and Staphylococcus aureus (S. aureus).