Chemical profiling of mycosporine‐like amino acids in twenty‐three red algal species

Abstract

Rhodophyta produce a variety of chemically different mycosporine‐like amino acids (MAAs), compounds that are known as some of the strongest ultraviolet (UV) absorbing molecules in nature. Accordingly, they primarily act as photoprotectants against harmful levels of solar ultraviolet radiation in the UV‐A and UV‐B range. In order to get a deeper understanding of the chemical diversity of MAAs in red algae, pure standards of eleven mycosporine‐like amino acids were isolated from three different species ( Agarophyton chilense , Pyropia plicata and Champia novae‐zelandiae ) using various chromatographic methods. Their structures were confirmed by nuclear magnetic resonance and mass spectrometry. Four out of the eleven MAAs are reported for the first time in algae. In addition, a new high‐performance liquid chromatography method was developed for the separation of all isolated MAAs and successfully applied for the analysis of twenty‐three red algal species of marine origin. All of them contained MAAs, the most abundant compounds were shinorine, palythine, asterina‐330 and porphyra‐334. For some samples, the direct assignment of MAAs based on their UV spectra was not possible; therefore, the target analytes were enriched by a simple concentration step, followed by liquid chromatography‐mass spectrometry analysis of the extracts. This approach enabled a deeper insight into the MAA pattern of red algae, indicating that not only the four dominant ones are synthesized but also many others, which were often described as unknown compounds in previous studies.

Distribution, Contents, and Types of Mycosporine-Like Amino Acids (MAAs) in Marine Macroalgae and a Database for MAAs Based on These Characteristics

“…Note that in this application, it becomes very important to study the preparation and purification of MAAs. In fact, the extraction of MAAs in marine macroalgae has been involved in many studies which were mainly concentrated on the distribution [64,69,93,96,115], profile [120], physiological activity [55,67,71,104,[121][122][123][124], properties [56,82,93,125,126], chemical characterization [54] of MAAs and effects of some environment factors on MAAs [36,54,66,74,80,81,87,[102][103][104]110,126,127]. However, further their isolation and purification did not conduct.…”

“…A new MAA catenelline was isolated from Catenella repens [49]. MAAs in Chondrus crispus [57], Palmaria palmata [57], Porphyra dioica [57], Porphyra haitanensis [127] and Rhodymenia pseudopalmata [104] have been separated and identified. The preparation of porphyra-334 in Bangia atropurpurea [47], Eucheuma [128], Gracilaria changii [95], Porphyra vietnamensis [78], Porphyra MAAs were multi-functional compounds, namely included UV-photoprotective activity [54], antioxidant properties [90,118], and other possible activities, such as anti-desiccant, protective agents against temperature variations [119], and etc.…”

“…The preparation of porphyra-334 in Bangia atropurpurea [47], Eucheuma [127], Gracilaria changii [94], Porphyra vietnamensis [78], Porphyra yezoensis [128], and Rhodymenia pseudopalmata [103] has been reported. Isolation and purification of others MAAs in Agarophyton chilense [104], Ahnfeltiopsis devoniensis [39,129], Bostrychia scorpioides [76,77], Champia novae-zelandiae [104], Chlamydomonas hedlyei [123], Chondracanthus chamissoi [50], Chondrus crispus [41,57], Gelidium corneum [39,129], Gelidium lingulatum [50], Gracilaria changii [108,130], Gracilaria cornea [87], Mastocarpus stellatus [76,77], Palmaria decipiens [123], Palmaria palmata [57,131], Porphyra dioica [57], Porphyra rosengurttii [39,119], Porphyra sp. [32,131], Porphyra tenera [123,132], Porphyra yezoensis [76,77,105,128], Pyropia leucosticte [39] and Pyropia plicata [104], such as palythine, palythinol, shinorine, usujirene and etc., that were often used as standards for identification and quantification of MAAs, also have been researched.…”

Quantitative and Qualitative HPLC Analysis of Mycosporine-Like Amino Acids Extracted in Distilled Water for Cosmetical Uses in Four Rhodophyta

“…These molecules may interact with the eluent solvent and MAAs presents in the samples increasing their molecular weights and changing their polarity, and therefore their elution times [30]. Matrix effect is minimized in analysis of purified and partially purified MAA extracts [20,38]. Although, why this matrix effect could occur under some conditions and not others must be investigated.…”

“…Quantification was made by using published extinction coefficients [58,59] and the formula found in Pliego-Cortes et al [60]. When we obtained a mixed unidentifiable peak, we estimated the total MAA concentration using an average extinction coefficient for those MAAs present in the species [38].…”