Department of Pharmacognosy, Institute of Pharmacy, University of Innsbruck, A-6020 Innsbruck, Austria.
Mar Drugs. 2022 Jan 27;20(2):106. doi: 10.3390/md20020106.
Marine rhodophyta are known to synthesize specific secondary metabolites, mycosporine-like amino acids (MAAs), to protect themselves from harmful UV-radiation. Shinorine and porphyra-334 are among the most abundant representatives of this compound class. In the present work, a novel approach for their isolation is described. As a first step, a fast centrifugal partition chromatography method, with an aqueous two-phase system comprising water, ethanol, ammonium sulfate and methanol in ascending mode, was developed to isolate the two MAAs from crude aqueous-methanolic extracts of three algal species within 90 min. The compounds could be isolated when just one of them was present in a sample or also both at the same time. By employing solid phase extraction as a second purification step, the individual MAAs were obtained in high purity and good quantity within a much shorter time frame than the established purification protocols, e.g., semi-preparative HPLC. For example, from 4 g sp. (Nori) crude extract, 15.7 mg shinorine and 36.2 mg porphyra-334 were isolated. Both were highly pure, as confirmed by TLC, HPLC-MS and NMR analyses.
海洋红藻被认为能合成特定的次生代谢产物——菌氨酸类似物（MAAs），以保护自己免受有害的紫外线辐射。节旋藻和条斑紫菜 334 是该化合物类别的最丰富的代表之一。在本工作中，描述了一种新的分离方法。作为第一步，开发了一种快速离心分配色谱法，采用包含水、乙醇、硫酸铵和甲醇的两相体系，以升序模式，在 90 分钟内从三种藻类的粗水-甲醇提取物中分离出两种 MAAs。当样品中仅存在一种化合物或同时存在两种化合物时，均可对其进行分离。通过采用固相萃取作为第二步纯化步骤，与已建立的纯化方案（例如半制备 HPLC）相比，可在更短的时间内以高纯度和良好的产量获得单个 MAAs。例如，从 4 克 sp.（紫菜）粗提取物中分离出 15.7 毫克节旋藻和 36.2 毫克条斑紫菜 334。通过 TLC、HPLC-MS 和 NMR 分析确认，这两种化合物均为高纯度。
