Silver Nanoparticles Biosynthesized with Spruce Bark Extract-A Molecular Aggregate with Antifungal Activity against Species.

Due to their high content of biomolecules, combined with silver's well known antimicrobial potential, silver nanoparticles biosynthesized using spruce bark (AgNP SBEs) demonstrate antibacterial and antioxidant activity, making them a versatile option for developing new antimicrobial agents that might be used for medical treatment or as adjuvants for the classical agents. This study aims to analyze if silver nanoparticles (AgNPs) mediated by spruce bark extract (SBE) and silver salts (AgNP SBE Acetate, AgNP SBE Nitrate) presents antifungal activity against five different spp., synergistic activity with fluconazole, and if they interact with some virulence factors of . AgNP SBEs presented MICs (minimum inhibitory concentrations) for all the five tested spp. AgNP SBEs inhibited the growth of , and exerted synergistic activity with fluconazole for and , and inhibited biofilm production for , , and . MICs of AgNP SBE Acetate significantly inhibited the production of germ tubes of . The expression of   gene was down-regulated by the short-time treatment with MICs of AgNP SBE Acetate, while and genes were up-regulated by the AgNPs MICs. These results emphasize the potential of using the AgNP SBEs as treatments/adjuvants options, not only against the redundant but also for the non-albicans species (which are not as frequently involved in human pathologies, but, sometimes, can be more aggressive).