Recent advances in recovering bioactive compounds from macroalgae and microalgae using subcritical water extraction: Prospective compounds and biological activities.

Algae, widely as a valuable marine biomass, are appreciated globally for their unique chemical compositions and exceptional nutritional benefits. Scientists are increasingly focusing on valorizing algae biomass to recover polysaccharides and bioactive extracts. Conventional methods commonly used to extract bioactive compounds have several limitations. Subcritical water extraction (SWE) is a green extraction technology for extracting bioactive compounds from natural products. SWE has garnered significant attention attributed to its use of safe solvent (water), high extraction efficiency, economical, promising application potential and environmental friendliness. The factors influencing the extraction of bioactive compounds using SWE, including temperature, pressure, extraction time, particle size, and solid-to-solvent ratio, were thoroughly discussed. Furthermore, these bioactive compounds exhibit antioxidant, antimicrobial, antihypertensive, anticancer, and antidiabetic properties. The bioactive compounds from the hydrolysates were not purified, but future research could address this for potential applications. This study provides valuable reference points for both academia and industrial-scale commercialization.