Bioactive metabolites from the endophytic fungus Epicoccum sorghinum QA-20 isolated from Artemisia argyi with antibacterial activity against aquaculture pathogens and antioxidant potential

Artemisia argyi H. Lév. while compound 7 exhibited DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS (2,2’-azino-bis) scavenging capacity (IC 50 =15.81 ± 0.52and 32.95 ± 0.72 μ g/mL, respectively), comparable to that of vitamin C (IC 50 = 11.62 ± 0.85 and 28.09 ± 1.40 μ g/mL, respectively). This study demonstrates that endophytes derived from A. argyi are a valuable source of novel antibacterial and antioxidant natural products. • 40 endophytic fungi were isolated from Artemisia argyi . • Secondary metabolites of Epicoccum sorghinum QA-20, exhibiting strong antibacterial activity, were investigated. • One previously undescribed polyketide and 12 known compounds were identified. • Antibacterial and antioxidant assays identified two key bioactive leads: compound 6 (antibacterial) and compound 7 (antioxidant).