Botanical and marine extracts have been used in cosmetic products as natural antioxidants or UV-absorbers to reduce the use of organic UV filters. However, despite the high UV exposure of Antarctic macroalgae that induces the production of photoprotective compounds, the use of marine macroalgae extracts for photoprotection has been little explored. Thus our objective was to assess the photoprotective potential and the toxicity of extracts from two red macroalgae Curdiea racovitzae and Iridaea cordata. Chemical characterization was based on the qualitative and quantitative analyses of mycosporine-like amino acids (MAAs) by high performance liquid chromatography coupled to mass spectrometry. Photoprotective properties were assessed by UV spectrophotometry and photostability assay. Antioxidant capacity was studied by DPPH and superoxide radical scavenging assays. UVB and UVA photoprotection was assessed in keratinocytes by cell viability analysis after UVB irradiation and quantification of intracellular reactive oxygen species (ROS) induced by UVA, respectively. Toxicity was estimated by cytotoxicity, phototoxicity and HET-CAM (Hen's egg test-chorioallantoic membrane) assays. Red algae extracts had high concentrations of MAAs, mainly consisted of palythine. The extracts absorbed in the UVB and UVA-II and were photostable. The C. racovitzae extract showed antioxidant activity against superoxide radicals. In addition, the C. racovitzae (1.0 and 0.5 mg/mL) and I. cordata (1.0 mg/mL) extracts had an UVB photoprotection similar to benzophenone-3, which was dependent on the total MAAs concentration. Besides, the C. racovitzae extract decreased ROS generation by 31 and 24% at 100 and 50 μg/mL, respectively. Furthermore, it was more effective in reducing ROS generation than quercetin and Helioguard 365®. Finally, both extracts were considered to be non-cytotoxic, non-phototoxic and non-irritant. Therefore, the C. racovitzae extract is a good candidate to be added to anti-aging and sunscreen formulations in order to protect against oxidative stress and to improve the absorption spectra of UV filters.

植物和海洋提取物已作为天然抗氧化剂或紫外线吸收剂用于化妆品中，以减少有机紫外线过滤剂的使用。然而，尽管南极大型藻类的高紫外线暴露诱导了光保护性化合物的产生，但是很少有人探索使用海洋大型藻类提取物进行光保护。因此，我们的目的是评估两种红色大型藻类Curdiea racovitzae和Iridaea cordata的提取物的光防护潜力和毒性。。化学表征是基于高效液相色谱-质谱联用对霉菌素样氨基酸（MAA）进行定性和定量分析的。通过UV分光光度法和光稳定性测定法评估光保护性能。通过DPPH和超氧化物自由基清除试验研究了抗氧化能力。分别通过对UVB照射后的细胞生存力分析和定量由UVA诱导的细胞内活性氧（ROS）来评估角质形成细胞中的UVB和UVA光保护。毒性通过细胞毒性，光毒性和HET-CAM（Hen's卵测试-绒毛膜尿囊膜）测定进行评估。红藻提取物具有高浓度的MAA，主要由黄嘌呤组成。提取物被UVB和UVA-II吸收，并具有光稳定性。的C. racovitzae提取物显示出对超氧自由基的抗氧化活性。此外，C。racovitzae（1.0和0.5 mg / mL）和I. cordata（1.0 mg / mL）提取物具有类似于二苯甲酮3的UVB光保护作用，这取决于总的MAA浓度。此外，C。racovitzae提取物在100和50μg/ mL时分别使ROS生成减少了31％和24％。此外，与槲皮素和Helioguard365®相比，它在减少ROS产生方面更有效。最后，两种提取物均被认为是无细胞毒性，无光毒性和无刺激性的。因此，C。racovitzae 提取物是添加到抗衰老和防晒配方中的很好的候选者，以防止氧化应激并改善UV滤光片的吸收光谱。