Publications

This section compiles peer-reviewed scientific publications arising from Revalgae activities

Trentin, R., Macquigneau, W., Braga, T. et al. Invasive but valuable: exploring the lipidome of Rugulopteryx okamurae for biotechnological applications. J Appl Phycol 38, 633–646 (2026). https://doi.org/10.1007/s10811-025-03770-z

The invasive alga Rugulopteryx okamurae has spread widely across European coasts, causing significant ecological and economic damage. In Portugal, mitigation strategies now include biomass valorisation within circular bioeconomy frameworks. While previous studies have identified phenolics, carotenoids, polyunsaturated fatty acids, proteins, and diterpenoids in R. okamurae, a comprehensive characterization of its lipid fraction is lacking. In this context, this study hypothesized that the lipid fraction of R. okamurae contains bioactive molecules that could support pharmaceutical, nutraceutical, or aquaculture applications. To explore this potential, lipids were extracted using the Bligh and Dyer method and evaluated for in vitro antioxidant and cytotoxic activities. Fatty acid profiling was performed by GC–MS, and untargeted lipidomics was conducted via UHPLC–HR–MS/MS. The extract showed marked antioxidant activity (FRAP: EC50 = 1.16 mg mL⁻1) and strong cytotoxicity against tumoral cell lines (B16: EC50 = 12.69 µg mL⁻1; HepG2: EC50 = 23.04 µg mL⁻1; SH-SY5Y: EC50 = 38.58 µg mL⁻1) and a non-tumoral line (HEK 293: EC₅₀ = 23.91 µg mL⁻1). Carotenoids (0.98 mg g⁻1 DW) and terpenoids (46.37 mg LE g⁻1 DW) may underlie these activities. The lipid fraction was rich in saturated (42.64%), monounsaturated (32.74%), and polyunsaturated (24.63%) fatty acids, mainly esterified into bioactive lipid classes. Bio-guided fractionation should now be pursued to isolate the cytotoxic components for antitumor evaluation, while enabling the safe exploitation of non-toxic lipid fractions in cosmeceutical, nutraceutical, or feed applications.

D’Unienville, A., Lasnel, L., Macquigneau, W., Trentin, R., Pais, A. C. S., Rodrigues, M. J., Santos, S. A. O., & Custódio, L. (2026). Chemical and Bioactivity Profiling of the Invasive Macroalga Rugulopteryx okamurae Collected in Southern Portugal Supporting Biotechnological Valorisation Approaches. Journal of Marine Science and Engineering, 14(7), 683. https://doi.org/10.3390/jmse14070683

The invasive brown macroalga Rugulopteryx okamurae has rapidly expanded across the Mediterranean–Atlantic region, generating severe ecological impacts. Nevertheless, the considerable amount of biomass available creates opportunities for valorisation within circular bioeconomy frameworks. This study provides an integrated characterization of the chemical profile and bioactivities of freshly collected floating biomass of R. okamurae from southern Portugal. Proximate composition was determined, and lipophilic (hexane) and hydrophilic (water) extracts were analyzed by GC–MS and spectrophotometric methods. Antioxidant activity was assessed using complementary radical-scavenging, reducing power, and metal-chelation assays, and enzyme inhibition was evaluated against targets associated with neurodegenerative, metabolic, and dermatological disorders. The lipophilic fraction was dominated by long-chain alkanes (≈101 mg/g extract) and sterols, particularly fucosterol (≈43 mg/g extract), but exhibited low radical-scavenging capacity (no EC50 reached in DPPH or ABTS assays), and no relevant enzyme inhibition. In contrast, the water extract contained measurable phlorotannins (6.61 mg PGE/g extract) and showed moderate antioxidant (ABTS: EC50 = 5.17 mg/mL; FRAP: EC50 = 0.78 mg/mL) and enzyme inhibition activities (BChE: IC50 = 5.17 mg/mL; tyrosinase: IC50 = 0.78 mg/mL). Compared with previous studies on R. okamurae, this work applies a systematic fractionation of biomass from southern Portugal into polar and non-polar fractions and, for the first time, correlates the resulting detailed chemical profiles with multiple bioactivities. This approach revealed a clear functional differentiation between fractions, with bioactivity being mainly associated with polar metabolites. Overall, these findings highlight the value of structured extraction strategies for biomass valorisation and support the sustainable management of R. okamurae.