In vitro evaluation of antimicrobial and antioxidant activities of algal extracts

Abstract

The aim of this study was to evaluate the antioxidant capacity, the antimicrobial proprieties of algae Ascophyllum nodosum and Schizochytrium spp. against one of major swine enteric pathogen Escherichia coli O138 by broth macro-dilution method in Luria–Bertani (LB) medium. The antimicrobial effect of the algal extracts at supplementation of 0.12%, 0.06% and 0.03% (v/v) on E. coli O138, genetically characterised by PCR, was evaluated by following the bacterial growth. The antioxidant activity was determined by the ABTS Radical Cation Decolorisation Assay. In particular, the log10 E. coli used as control resulted significantly higher than 0.12% at 3 hours (8.82 ± 0.07 and 8.18 ± 0.07 log10 cells/mL, respectively; p