Abstract
UV-absorbing compounds, such as mycosporine-like amino acids (MAAs), are a group of secondary metabolites present in many marine species, including red seaweeds. In these organisms, the content and proportion of the composition of MAAs vary, depending on the species and several environmental factors. Its high cosmetic interest calls for research on the content and composition of MAAs, as well as the dynamics of MAAs accumulation in seaweeds from different latitudes. Therefore, this study aimed to survey the content of UV-absorbing MAAs in three Subantarctic red seaweeds during a seasonal cycle. Using spectrophotometric and HPLC techniques, the content and composition of MAAs of intertidal Iridaea tuberculosa, Nothogenia fastigiate, and Corallina officinalis were assessed. Some samples were also analyzed using high-resolution mass spectrometry coupled with HPLC-ESI-MS in order to identify more precisely the MAA composition. I. tuberculosa exhibited the highest MAA values (above 1 mg g−1 of dried mass weight), while C. officinalis showed values not exceeding 0.4 mg g−1. Porphyra-334 was the main component in N. fastigiata, whereas I. tuberculosa and C. officinalis exhibited a high content of palythine. Both content and composition of MAAs varied seasonally, with high concentration recorded in different seasons, depending on the species, i.e., winter (I. tuberculosa), spring (N. fastigiata), and summer (C. officinalis). HPLC-ESI-MS allowed us to identify seven different MAAs. Two were recorded for the first time in seaweeds from Subantarctic areas (mycosporine-glutamic acid and palythine-serine), and we also recorded an eighth UV-absorbing compound which remains unidentified.
Highlights
Recovery of the ozone layer is expected by the end of this century
In high-performance liquid chromatography (HPLC) analyses, chromatograms showed the presence of mycosporine-like amino acids (MAAs), which varied according to species
This study reveals that the contents and composition of UV-absorbing MAAs experience strong seasonal changes in the three intertidal species
Summary
Recovery of the ozone layer is expected by the end of this century. Several factors could still contribute to the increase of ultraviolet radiation (UVR), including the decrease of aerosols and cloud cover interacting with climate change [1,2]. In the expected scenario, photoprotection of the biosphere will still be relevant [1,3]. Marine primary producers possess several compounds that act as photoprotectors against excess solar radiation. Mar. Drugs 2020, 18, 75; doi:10.3390/md18020075 www.mdpi.com/journal/marinedrugs
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
