Mycosporine-like amino acids profile in red algae from high UV-index geographical areas (San Andrés Island and La Guajira) of the Colombian Caribbean coast

Mycosporine-like amino acids (MAAs) are photoprotective compounds with diverse applications in biotechnology, pharmaceuticals, and cosmetics. This study aimed to identify and quantify the full range of MAAs present in red macroalgae collected from high UV-Index geographical areas (San Andrés Island and La Guajira) of the Colombian Caribbean coast. We focused on abundant species from the midlittoral zone, covering contrasting UV-index periods throughout 2022. Quantification was performed using the validated calibration curve of porphyra-334, corrected with the molar extinction coefficients for shinorine, palythine, and asterine, considering the area under the curve at their maximum absorption wavelengths for accurate MAA concentration estimates. Total MAAs content was obtained from different species of the orders Ceramiales, Gigartinales, Gracilariales, Halymeniales, and Nemiales collected from the Colombian Caribbean coast. Several species from this region, characterized by its high UV-Index, exhibited higher MAAs concentrations compared to those reported in other tropical regions. The highest total MAAs content was found in Bryocladia cuspidata with 15.93 ± 0.02 mg.g^-1 DW. However, other species showed significant potential, with values above 6 mg.g^-1 DW such as Centroceras micracanthum, and Laurencia obtusa. Other species had values around 3 mg.g^-1 DW, such as Hypnea cf. caraibica, Gracilaria tikvahiae, and Grateloupia cf. filicina. Some species are viable for sustainable MAAs extraction, highlighting the relevance of Colombian red macroalgae as sources for photoprotective applications.