UV‐induced synthesis/accumulation of photoprotective pigments and antioxidant activity were investigated in the hot‐spring cyanobacterium Leptolyngbya cf. fragilis. The results indicated that UV radiation may induce biosynthesis of carotenoids, allophycocyanin, phycoerythrin, and scytonemin while phycocyanin degrades in response to longtime UV radiation. Moreover, pigment composition of L. cf. fragilis was significantly altered with increasing UV radiation times, probably due to destruction and resynthesis of accessory pigments as an adaptation strategy to UV stress. The in vitro antioxidant analysis of different extracts of UV treated cyanobacteria exhibited concentration‐dependent antioxidant activity. Ethyl acetate extract of 72 h UV treatment showed maximum total antioxidant activity (IC50 = 71.73 ± 5.3 μg mL−1) followed by ethyl acetate control (non‐UV irradiated) extract (IC50 = 109.43 ± 2.76 μg mL−1). This is the first report for the UV‐induced synthesis of photoprotective pigments and their antioxidant activity in L. cf. fragilis.

中文翻译：

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不同紫外线辐射对温泉蓝藻Leptolyngbya光保护色素及抗氧化活性的影响 脆弱的

在温泉蓝细菌 Leptolyngbya 中研究了紫外线诱导的光保护色素的合成/积累和抗氧化活性。脆弱的。结果表明，紫外线辐射可能会诱导类胡萝卜素、别藻蓝蛋白、藻红蛋白和胞嘧啶核苷的生物合成，而藻蓝蛋白会因长时间的紫外线辐射而降解。此外，L. cf. 的颜料成分。随着紫外线辐射时间的增加，脆弱性显着改变，这可能是由于辅助色素的破坏和再合成作为对紫外线压力的适应策略。紫外线处理过的蓝藻不同提取物的体外抗氧化分析显示出浓度依赖性的抗氧化活性。72 小时紫外线处理的乙酸乙酯提取物显示出最大的总抗氧化活性（IC50 = 71.73 ± 5。3 μg mL-1)，然后是乙酸乙酯对照（非紫外线照射）提取物（IC50 = 109.43 ± 2.76 μg mL-1）。这是 L. cf. 中紫外线诱导合成光保护色素及其抗氧化活性的第一份报告。脆弱的。