In vitro evaluation of antimicrobial and antioxidant activities of algal extracts

This study explores the potential of two algae species - Ascophyllum nodosum and Schizochytrium spp. - as natural alternatives to antibiotics in pig production. Conducted in vitro, the research evaluates both antimicrobial and antioxidant properties, particularly against E. coli O138, a major cause of post-weaning diarrhea in pigs. Results show that A. nodosum demonstrates dose-dependent antibacterial activity, while the combination of both algae exhibits enhanced antioxidant effects, demonstrating synergistic potential to target distinct physiological pathways. These findings highlight the promise of algal extracts as functional feed additives that could support gut health and reduce reliance on antibiotics, although further in vivo validation is needed.