Molecules

The Portuguese Atlantic coast harbors a remarkably diverse macroalgal flora, shaped by the intersection of Lusitanian, Mediterranean, and boreal biogeographic influences. This diversity is reflected in the rich repertoire of secondary metabolites produced by local seaweeds, including halogenated compounds, terpenoids, phlorotannins, mycosporine like amino acids, sulfated polysaccharides, and unique phenolic structures. These metabolites exhibit a wide range of bioactivities, antioxidant, anti-inflammatory, antimicrobial, antiviral, antifouling, antitumoral, and neuroprotective, positioning Portuguese seaweeds as promising sources of novel bioactive agents. This review synthesizes the current state of knowledge on the chemical diversity and biological properties of metabolites isolated from seaweeds along the Portuguese Atlantic coast. We examine species-specific metabolite profiles, ecological drivers of chemical variability, and advances in extraction, purification, and structural elucidation. Emerging applications in pharmaceuticals, nutraceuticals, cosmeceuticals, and sustainable biomaterials are discussed, alongside the potential of seaweed derived compounds to support blue bioeconomy development. Finally, we identify research gaps and propose future directions for bioprospecting, metabolomics, and biotechnological exploitation of this underexplored marine resource.

Nervonic acid (NA), an ultra-long-chain monounsaturated fatty acid, has attracted widespread attention in recent years due to its notable neuroprotective and antioxidant effects. In this study, a structured lipid was developed by enzymatically interesterifying coconut oil, palm stearin, and NA. The effects of lipase type, reaction temperature, time, and enzyme dosage on NA incorporation were investigated. The highest NA content in the structured lipid was achieved under optimized conditions: a reaction temperature of 64.6 °C, a reaction time of 7.17 h, and an enzyme dosage of 8.46%. Subsequently, a machine learning model was constructed to predict the sliding melting point. The NA-rich structured lipid, designed and prepared for use as a plastic fat, comprised 59.34% unsaturated fatty acids (46.76% NA) and exhibited β’ crystal polymorphism. This combined experimental and computational approach is a reliable strategy for preparing functional structured lipids.

Near-critical and supercritical carbon dioxide (SC-CO₂) is extensively utilized in high-pressure separation, extraction, polymer processing, and carbon capture and utilization (CCU) technologies owing to its tunable density, low viscosity, high diffusivity, and environmentally benign nature. Reliable phase equilibrium data are indispensable for process design and optimization, especially in the near-critical region characterized by pronounced non-idealities, high compressibility, and density fluctuations. This review synthesizes experimental phase behaviour studies for binary mixtures of CO₂ with diverse components, including hydrocarbons, alcohols, ethers, esters, ketones, water, monomers/polymers, ionic liquids (ILs), and deep eutectic solvents (DESs), compiling extensive vapour–liquid equilibrium (VLE), liquid–liquid equilibrium (LLE), and critical data across industrially relevant pressure (up to 40 MPa) and temperature (up to 400 K) ranges. It critically evaluates analytical (sampling and non-sampling) and synthetic methodologies, addressing challenges in CO₂-rich phase handling, depressurization artefacts, and near-critical phenomena, while assessing data consistency against established reliability criteria. Key trends emerge, such as enhanced solubility with increasing pressure and CO₂ density, chain-length dependencies in hydrocarbons and alcohols, and Lewis acid–base interactions driving solvation in polar systems. The review highlights gaps in multicomponent data and proposes integrating high-quality experiments with advanced thermodynamic modelling to enhance predictive accuracy. Future directions emphasize high-precision in situ techniques, expanded datasets for complex mixtures, and novel CO₂-philic solvents to advance sustainable SC-CO₂ applications.