Microalgae can be cultivated for producing high-valued products through the production of enzymes to offset the cost of CO₂ sequestration, providing financial incentives. The viability of algae in the photobioreactor needs to be monitored to ensure biologically active live cells. In this study, we explored a simple fluorometry method for differentiation of live and dead algal cells in photobioreactors by fluorescein diacetate (FDA) and propidium iodide (PI) fluorescence staining. FDA stains fluorescent green to the living cells while PI stains the dead cells, allowing the discrimination of live and dead cells. The method was evaluated using two green algae and two strains of cyanobacteria grown in shake flasks and a continuously stirred photobioreactor. The method was found applicable for Chlorella pyrenoidosa and Synechococcus 7002 but was not applicable for the cultures of Scenedesmus dimorphus and Synechococcus elongatus 7942. We conclude that FDA is a good stain for monitoring live algal cells in photobioreactors but its applicability to individual species of algae must be evaluated.

中文翻译：

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双乙酸荧光素和碘化丙啶荧光染色在监测藻类生长和生存能力中的适用性

可通过生产酶来培养微藻，以生产高价值的产品，以抵消CO ₂隔离的成本，从而提供经济诱因。需要监测光生物反应器中藻类的生存能力，以确保具有生物活性的活细胞。在这项研究中，我们探索了一种简单的荧光分析方法，通过荧光素二乙酸酯（FDA）和碘化丙啶（PI）荧光染色来区分光生物反应器中的活藻和死藻细胞。FDA将活细胞染成绿色的荧光，而PI将死细胞染成绿色，从而可以区分活细胞和死细胞。使用在摇瓶和连续搅拌的光生物反应器中生长的两种绿藻和两种蓝细菌菌株对方法进行了评估。该方法适用于小球藻小球藻和Synechococcus 7002，但不适用于双歧藻和伸长Synechococcus elongatus 7942的培养。我们得出结论，FDA是监测光生物反应器中活藻细胞的良好染色剂，但必须评估其对单个藻类的适用性。