Ferreira, Carolina A. M.Félix, RafaelFélix, CarinaJanuário, Adriana P.Alves, NunoNovais, Sara C.Dias, Juliana R.Lemos, Marco F.L.2021-08-052021-08-052021Ferreira, C.A.M.; Félix, R.; Félix, C.; Januário, A.P.; Alves, N.; Novais, S.C.; Dias, J.R.; Lemos, M.F.L. A Biorefinery Approach to the Biomass of the Seaweed Undaria pinnatifida (Harvey Suringar, 1873): Obtaining Phlorotannins-Enriched Extracts forWound Healing. Biomolecules 2021, 11, 461. https:// doi.org/10.3390/biom110304612218-273Xhttp://hdl.handle.net/10400.8/6014This study was supported by UID/MAR/04292/2020 and UIDB/04044/2020, UIDP/04044/2020, with funding from FCT/MCTES through national funds, and by the grant awarded to Rafael Félix (SFRH/ BD/139763/2018). The authors also wish to acknowledge the support of the European Union through EASME Blue Labs project AMALIA, Algae-to-MArket Lab IdeAs (EASME/EMFF/2016/1.2.1.4/03/SI2.750419), project VALORMAR (Mobilizing R&TD Programs, Portugal 2020) cofunded by COMPETE (POCI-01-0247-FEDER-024517), the Integrated Programme of SR&TD “Smart Valorization of Endogenous Marine Biological Resources Under a Changing Climate” (reference Centro01-0145-FEDER-000018), and RD&T copromotion project ORCHESTRA (nº 70155), PAMI (Portuguese Additive Manufacturing Initiative—ROTEIRO/0328/2013 (Nº 022158) and MATIS (Sustainable Industrial Materials and Technologies—CENTRO-01-0145-FEDER-000014) cofunded by Centro 2020 program, Portugal 2020, European Union, European Regional Development Fund, and SAICTPAC/0019/2015—LISBOA-01-0145-FEDER-016405 Oncologia de Precisão: Terapias e Tecnologias Inovadoras (POINT4PAC) through the European Regional Development Fund.Brown seaweeds are recognized sources of compounds with a wide range of properties and applications. Within these compounds, phlorotannins are known to possess several bioactivities (e.g., antioxidant, anti-inflammatory, and antimicrobial) with potential to improve wound healing. To obtain phlorotannins enriched extracts from Undaria pinnatifida, a biorefinery was set using lowcost industry-friendly methodologies, such as sequential solid–liquid extraction and liquid–liquid extraction. The obtained extracts were screened for their antioxidant and antimicrobial activity against five common wound pathogens and for their anti-inflammatory potential. The ethanolic wash fraction (wE100) had the highest antioxidant activity (114.61 +- 10.04 mmol mg-1 extract by Diphenyl-1-picrylhydrazyl (DPPH) and 6.56 +-1.13mMeq. Fe II mg-1 extract by and Ferric Reducing Antioxidant Power (FRAP)), acting efficiently against Gram-negative (Pseudomonas aeruginosa) and Gram-positive (Staphylococcus aureus) bacteria, and showing a nitric oxide production inhibition over 47% when used at 0.01 ug mL-1. NMR and FTIR chemical characterization suggested that phlorotannins are present. Obtained fraction wE100 proved to be a promising candidate for further inclusion as wound healing agents, while the remaining fractions analyzed are potential sources for other biotechnological applications, giving emphasis to a biorefinery and circular economy framework to add value to this seaweed and the industry.engAnti-inflammatoryAntimicrobialAntioxidantCircular economyPhlorotanninsjournal article10.3390/biom11030461