Emerging methods to extract bioactive compounds from brown algae: a comprehensive review of performance, readiness, and sustainability

Brown algae (Phaeophyceae) are an important source of bioactive compounds with promising applications in many sectors. However, traditional extraction methods are often resource-intensive, solvent-demanding, and environmentally burdensome, with limitations in selectivity and process efficiency. This review examines recent studies (2014–2025) on emerging extraction methods for brown algae, including pulsed electric field-assisted extraction (PEF-AE), pressurized liquid extraction (PLE), microwave-assisted extraction (MAE), ultrasound-assisted extraction (UAE), subcritical water extraction (SWE), supercritical carbon dioxide extraction (SCCO 2 ), enzyme-assisted extraction (EAE), and natural deep eutectic solvents (NADES). A central contribution of this review is the implementation of a tailored rubric to assess technology readiness level (TRL) and societal readiness level (SRL) across these extraction platforms. These methods are critically evaluated in terms of extraction performance, technical advantages, limitations, and their economic and environmental implications. Finally, future research directions are discussed to optimize these methods, overcome current challenges, and fully realize the industrial potential of brown algae-derived bioactive compounds.