Seaweeds are potentially excellent sources of bio-active metabolites that could represent useful leads in the de-velopment of new functional ingredients in pharmaceuticaland cosmetic industries. In the last decade, new marinebioprocess technologies have allowed the isolation of sub-stances with biological properties. The brown algaSargassum muticum (Yendo) Fensholt (Ochrophyta) was en-zymatically hydrolyzed to prepare water-soluble extracts byusing six different commercially available carbohydrate-degrading enzymes and two proteases. Evaluation of 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antiox-idant power (FRAP) antioxidant, tyrosinase, elastase, and bio-film inhibition, antibacterial and antiviral activities as well asevaluation of cytotoxicity were realized for each extract. Totalphenolic content was measured for extract characterization,and solid-phase extraction was useful to purify the enzymaticextract. Soluble total phenolic content of S. muticumViscozyme extract was highest with 6.4% of dry weight.Enzymatic Celluclast and Viscozyme extracts had the lowestvalue of DPPH IC50 indicating a strong antiradical activity,0.6 mg mL−1, in comparison with other enzymes. The ferricreducing antioxidant power ranged between 48.7 μM Fe 2+ Eq,digested with Viscozyme, and 60.8 μM Fe 2+ Eq, digested withAmyloglucosidase. Tyrosinase inhibition activity ofS. muticum Neutrase extract was 41.3% higher compared toother enzymes. Elastase inhibition activity of S. muticumShearzyme extract had highest activity (32.8%). All enzymat-ic extracts showed no cytotoxic effect towards the kidney Verocells. Meanwhile, only S. muticum Neutrase and Alcalase ex-tracts exhibited potential antiviral activity. In addition,S. muticum Viscozyme and Shearzyme extracts showed prom-ising activity in suppressing the biofilm formation againstPseudomonas aeruginosa and Escherichia coli, respectively. Purification of S. muticum Viscozyme extracts by solid-phaseextraction managed to concentrate the phenolic content andimprove the bioactivity. These results indicate the promisingpotential of enzyme-assisted followed by solid-phase extrac-tion in recovering phenolic content and in improving itsbioactivity.