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. Sargassum cf. ramifolium and Sargassum fluitans 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.

This work studied the extraction of bioactive metabolites from twelve Colombian marine macroalgae samples. Macroalgae samples were collected from the northeast coastal areas of Colombia and extracted using ultrasound-assisted liquid extraction with different Nades and compared them with reference solvents. The analysis of the extracts in-cludes preliminary chemical tests such as Folin-Ciocalteu quantifica-tion, DPPH assays, and MAAs identification using HPLC-DAD. In ad-dition, exploratory physicochemical tests measured the porosity of the sprayed material using the B.E.T. method and evaluated the Nades flow profile. HCl 5% extracts showed the highest yield of total phenolic compounds. It was 3-4% w/w for Gracilariopsis lemaneiformis, Hypnea sp., Pterocladiella capillacea, and Stypopodium zonale. Nades Beta-ine/Glucose/Water 1:1:5 had the highest efficiency extracting total phenolic compounds in most species. Over Sargassum polyceratium increasing the extraction scale, improved the recovery rate from 0 to 24 hours. The experiment reached saturation with 10 mL of BGluW115. It reproduced this result with different batches of glucose and betaine. MAAs concentrations ranged from 0.2 to 0.5 mg·g⁻¹ DW in the species analyzed with aqueous extractions. Nades FGW115 and BGW 115 allowed the detection of MAAs. Porosity differences among macroalgae did not affect phenolic recovery. Finally, Nades flow profiles exhibited Newtonian behavior.