Ferreira, Henrique S.Mouga, TeresaLourenço, SílviaMatias, Margarida H.Freitas, Marta V.Clélia Neves-Afonso2025-07-072025-07-072025-05-21Ferreira, H.S.; Mouga, T.; Lourenço, S.; Matias, M.H.; Freitas, M.V.; Afonso, C.N. Assessing High-Value Bioproducts from Seaweed Biomass: A Comparative Study of Wild, Cultivated and Residual Pulp Sources. Appl. Sci. 2025, 15, 5745. https://doi.org/10.3390/ app151057452076-3417http://hdl.handle.net/10400.8/13546This study aimed to evaluate the biochemical composition and bioactivities of biomass derived from wild (Laminaria ochroleuca and Saccorhiza polyschides) and cultivated (Macrocystis pyrifera) kelps, as well as industrially extracted residual pulp from M. pyrifera, to assess the potential production of high value bioproducts. All samples had a low lipid content, with M. pyrifera having the lowest (1.3% dw) and S. polyschides showing the highest value (3.3%). Fatty acids such as palmitic acid (C16:0), oleic acid (C18:1n-9 cis), alpha-linolenic acid (ALA, C18:3n-3), and eicosapentaenoic acid (EPA, C20:5n-3) were present, with the residual pulp having a distinctive n-6/n-3 ratio of less than one. The protein content was around 9% dry weight (dw) in all samples. The residual pulp and S. polyschides had the highest polyphenol content, with 4.86 and 4.94 mg GAE·g−1 extract, respectively. Hydroethanolic extracts (30–70%) confirmed Fe3+ reducing activity (FRAP) in all samples. These findings offer valuable insights on the biochemical composition and bioactivity of the kelp species under study and the residual kelp biomass (pulp), underlining their significant potential for applications in the field of Blue Biotechnology.engLaminaria ochroleucaMacrocystis pyriferaSaccorhiza polyschidesLipid profileProtein contentAntioxidant activityjournal article10.3390/app15105745