Chair of Marine Chemical Resource Development, Graduate School of Fisheries Sciences, Hokkaido University, Hakodate, Hokkaido 041-8611, Japan.
Laboratory of Marine Chemical Resource Development, Faculty of Fisheries Sciences, Hokkaido University, Hakodate, Hokkaido 041-8611, Japan.
Mar Drugs. 2020 Sep 30;18(10):502. doi: 10.3390/md18100502.
Mycosporine-like amino acids (MAAs) are the ultraviolet (UV)-absorbable compounds, which are naturally produced by cyanobacteria and algae. Not only these algae but also marine organisms utilize MAAs to protect their DNA from UV-induced damage. On the other hand, the content of MAAs in algae was changed by the environmental condition and season. In addition to the UV-protected function, the antioxidant capacity of MAAs can apply to the cosmetic sunscreen materials and anti-cancer for human health. In this study, we developed the efficient extraction method of MAAs from red alga dulse in Usujiri (Hokkaido, Japan) and investigated the monthly variation. We also evaluated the antioxidant capacity. We employed the successive extraction method of water and then methanol extraction. Spectrophotometric and HPLC analyses revealed that the yield of MAAs by 6 h water extraction was the highest among the tested conditions, and the content of MAAs in the sample of February was the most (6.930 µmol g dry weight) among the sample from January to May in 2019. Antioxidant capacity of MAAs such as crude MAAs, the purified palythine and porphyra-334 were determined by 2,2'-azinobis(3-ethylbenzothiazoline 6-sulfonic acid) (ABTS) radical scavenging and ferrous reducing power assays in various pH conditions, showing that the highest scavenging activity and reducing power were found at alkaline condition (pH 8.0).
肌氨酸类似物（MAAs）是可吸收紫外线（UV）的化合物，由蓝藻和藻类自然产生。不仅这些藻类，而且海洋生物利用 MAAs 来保护其 DNA 免受 UV 诱导的损伤。另一方面，藻类中 MAAs 的含量会随着环境条件和季节的变化而变化。除了具有 UV 保护功能外，MAAs 的抗氧化能力可应用于化妆品防晒材料和抗癌，以维护人类健康。在这项研究中，我们开发了一种从日本杵筑（北海道）红藻羊栖菜中提取 MAAs 的高效方法，并研究了其月变化。我们还评估了抗氧化能力。我们采用了水和甲醇分步提取的方法。分光光度法和 HPLC 分析表明，在测试条件中，6 小时水提取的 MAAs 产率最高，而 2019 年 1 月至 5 月期间，2 月样品中的 MAAs 含量最高（6.930 µmol g 干重）。粗 MAAs、纯化的 palythine 和 porphyra-334 的 MAAs 的抗氧化能力通过 2,2'-联氮双（3-乙基苯并噻唑啉-6-磺酸）（ABTS）自由基清除和亚铁还原力测定在各种 pH 条件下进行了测定，结果表明在碱性条件（pH 8.0）下具有最高的清除活性和还原能力。
