The effects of the extraction conditions on the recovery and isomerization of the UV-absorbing saclipins from the edible cyanobacterium Aphanothece sacrum by subcritical water were investigated. The extraction temperature (100–160 ℃) did not affect the extraction efficiency of saclipins, but the pressure (5–15 MPa) had a significant effect. The saclipin B (cis-configuration) ratio in the extract increased with extraction temperature. Since saclipin A (trans-configuration) is predominant in the raw material, it is proposed that thermal-induced cis-isomerization occurs during the extraction process under elevated temperature conditions. Furthermore, we found that extraction with subcritical water resulted in higher extraction and isomerization efficiencies of saclipins than extraction with organic solvents. Extracts obtained by subcritical water extraction (SWE) exhibited antioxidant and anti-elastase activities and the degree of the activities was affected by the extraction temperature (i.e., saclipin isomer ratio). These findings could facilitate the development of sunscreens with enhanced skincare benefits, utilizing naturally-derived bioactive compounds.

中文翻译：

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使用亚临界水从可食用蓝藻 Aphanothece sacrum 中提取和异构化紫外线吸收物质 saclipins


研究了提取条件对亚临界水从食用蓝藻 Aphanothece sacrum 中吸收紫外线的 saclipins 的回收和异构化的影响。提取温度 （100–160 °C） 对 saclipins 的提取效率没有影响，但压力 （5–15 MPa） 影响显著。提取物中的柳素 B （顺式构型） 比率随提取温度的增加而增加。由于蛋白 A（反式构型）在原料中占主导地位，因此提出在高温条件下的提取过程中发生热诱导的顺式异构化。此外，我们发现与有机溶剂萃取相比，亚临界水萃取导致 salipins 的萃取和异构化效率更高。亚临界水萃取 （SWE） 获得的提取物表现出抗氧化和抗弹性蛋白酶活性，活性程度受提取温度 （即 salipin 异构体比率） 的影响。这些发现可以促进利用天然衍生的生物活性化合物开发具有增强护肤功效的防晒霜。