Data_Sheet_1_Decay of Trichomes of Arthrospira platensis After Permeabilization Through Pulsed Electric Fields (PEFs) Causes the Release of Phycocyanin.docx

The cyanobacterium Arthrospira platensis is a promising source of edible proteins and other highly valuable substances such as the blue pigment-protein complex phycocyanin. Pulsed electric field (PEF) technology has recently been studied as a way of permeabilizing the cell membrane, thereby enhancing the mass transfer of water-soluble cell metabolites. Unfortunately, the question of the release mechanism is not sufficiently clarified in published literature. In this study, the degree of cell permeabilization (cell disintegration index) was directly measured by means of a new method using fluorescent dye propidium iodide (PI). The method allows for conclusions to be drawn about the effects of treatment time, electric field strength, and treatment temperature. Using a self-developed algorithm for image segmentation, disintegration of trichomes was observed over a period of 3 h. This revealed a direct correlation between cell disintegration index and decay of trichomes. This decay, in turn, could be brought into a direct temporal relationship with the release of phycocyanin. For the first time, this study reveals the relationship between permeabilization and the kinetics of particle decay and phycocyanin extraction, thus contributing to a deeper understanding of the release of cell metabolites in response to PEF. The results will facilitate the design of downstream processes to produce sustainable products from Arthrospira platensis.

蓝细菌（Cyanobacterium）钝顶节旋藻（Arthrospira platensis）是极具应用前景的食用蛋白来源，同时可提取藻蓝蛋白（phycocyanin）等高价值物质。近年来，脉冲电场（Pulsed electric field, PEF）技术被用于透化细胞膜，以提升水溶性细胞代谢物的传质效率。遗憾的是，现有公开文献尚未充分阐明该过程的释放机制。本研究采用基于荧光染料碘化丙啶（propidium iodide, PI）的新型方法，直接测定了细胞透化程度（即细胞崩解指数）。该方法可用于分析处理时长、电场强度及处理温度对透化效果的影响。通过自研的图像分割（image segmentation）算法，研究团队在3小时的观测周期内记录了藻丝（trichomes）的崩解过程，结果显示细胞崩解指数与藻丝衰减呈直接相关关系；而该藻丝衰减又与藻蓝蛋白的释放存在明确的时间关联。本研究首次揭示了细胞透化与颗粒崩解动力学及藻蓝蛋白提取之间的内在联系，有助于更深入理解脉冲电场作用下的细胞代谢物释放机制。相关研究结果可为基于钝顶节旋藻开发可持续产品的下游工艺设计提供指导。