Secalonic acid F1 derived from an endophytic fungus Periconia verrucosa as a potential antimicrobial agent against Staphylococcus aureus.

This article focuses on the antimicrobial potential of secalonic acid F1 (SF1), a secondary metabolite produced by the fungal endophyte Periconia verrucosa isolated from Rosa damascena. SF1 demonstrated significant inhibitory effects against Staphylococcus aureus, including methicillin-resistant strains, by reducing biofilm formation, disrupting cell membrane integrity, and downregulating key virulence genes such as staphylococcal enterotoxin A (sea) and accessory gene regulator A (agrA). Mechanistically, SF1 acts as a concentration-dependent bactericidal agent that impairs respiratory chain dehydrogenase activity through interaction with succinate dehydrogenase, and it also inhibits DNA, RNA, protein, lipid, and staphyloxanthin synthesis. The compound showed synergistic effects with antibiotics like ciprofloxacin and ampicillin, highlighting its potential as a multi-target antimicrobial agent against S. aureus.