Sustainable Extraction of Prospective Cosmetic Ingredients from Colombian Marine Macroalgae Using Natural Deep Eutectic Solvents

This study presents the results obtained from extracting and quantifying cosmetically valuable metabolites such as phenolic compounds and mycosporine-like amino acids (MAAs) from 12 samples of marine macroalgae collected in the Colombian Caribbean Sea. Natural deep eutectic solvents (NADESs) were prepared, physicochemically tested (viscosity, surface tension, pH, and conductivity), and then compared with water as the reference solvent to quantify phenolic compounds using the Folin-Ciocalteau test. With a simple extraction assay with water and ultrasound followed by ultraviolet spectral scanning the presence of MAAs was easily determined in several of the analysed samples, and then they were identified by HPLC-DAD. Hydrochloric acid solution at 5% extracted a higher content of phenolic compounds than NADES and water. The NADES that showed the highest phenolic compound extraction yield was a mixture of betaine, glucose, and water with 1:1:5 molar ratio. <i>Sargassum</i> cf. <i>ramifolium</i> and <i>Sargassum fluitans</i> showed the highest contents of phenolic compounds extracted with NADES, with 29.2 and 21.9 mg GAE/g DW, respectively. The results show that NADESs are an interesting alternative for the more efficient extraction of cosmetically valuable compounds such as phenolic compounds and mycosporine-type amino acids from marine macroalgae.