Haberkorn Iris, Off Cosima L, Besmer Michael D, Buchmann Leandro, Mathys Alexander
Sustainable Food Processing Laboratory, Institute of Food, Nutrition and Health, ETH Zurich, Zurich, Switzerland.
onCyt Microbiology AG, Zurich, Switzerland.
Front Bioeng Biotechnol. 2021 Mar 23;9:642671. doi: 10.3389/fbioe.2021.642671. eCollection 2021.
Microalgae are emerging as a next-generation biotechnological production system in the pharmaceutical, biofuel, and food domain. The economization of microalgal biorefineries remains a main target, where culture contamination and prokaryotic upsurge are main bottlenecks to impair culture stability, reproducibility, and consequently productivity. Automated online flow cytometry (FCM) is gaining momentum as bioprocess optimization tool, as it allows for spatial and temporal landscaping, real-time investigations of rapid microbial processes, and the assessment of intrinsic cell features. So far, automated online FCM has not been applied to microalgal ecosystems but poses a powerful technology for improving the feasibility of microalgal feedstock production through , real-time, high-temporal resolution monitoring. The study lays the foundations for an application of automated online FCM implying far-reaching applications to impel and facilitate the implementation of innovations targeting at microalgal bioprocesses optimization. It shows that emissions collected on the FL1/FL3 fluorescent channels, harnessing nucleic acid staining and chlorophyll autofluorescence, enable a simultaneous assessment (quantitative and diversity-related) of prokaryotes and industrially relevant phototrophic in mixed ecosystems of different complexity over a broad concentration range (2.2-1,002.4 cells ⋅μL). Automated online FCM combined with data analysis relying on phenotypic fingerprinting poses a powerful tool for quantitative and diversity-related population dynamics monitoring. Quantitative data assessment showed that prokaryotic growth phases in engineered and natural ecosystems were characterized by different growth speeds and distinct peaks. Diversity-related population monitoring based on phenotypic fingerprinting indicated that prokaryotic upsurge in mixed cultures was governed by the dominance of single prokaryotic species. Automated online FCM is a powerful tool for microalgal bioprocess optimization owing to its adaptability to myriad phenotypic assays and its compatibility with various cultivation systems. This allows advancing bioprocesses associated with both microalgal biomass and compound production. Hence, automated online FCM poses a viable tool with applications across multiple domains within the biobased sector relying on single cell-based value chains.
微藻正在成为制药、生物燃料和食品领域的下一代生物技术生产系统。微藻生物精炼厂的经济化仍然是主要目标，其中培养物污染和原核生物激增是损害培养稳定性、可重复性以及最终生产力的主要瓶颈。自动化在线流式细胞术（FCM）作为一种生物过程优化工具正越来越受到关注，因为它可以进行空间和时间景观分析、对快速微生物过程进行实时研究以及评估细胞固有特征。到目前为止，自动化在线FCM尚未应用于微藻生态系统，但它是一种强大的技术，可通过实时、高时间分辨率监测来提高微藻原料生产的可行性。该研究为自动化在线FCM的应用奠定了基础，这意味着其具有深远的应用前景，可推动和促进针对微藻生物过程优化的创新实施。研究表明，利用核酸染色和叶绿素自发荧光在FL1/FL3荧光通道上收集的排放物，能够在广泛的浓度范围（2.2 - 1,002.4个细胞·μL）内，对不同复杂程度的混合生态系统中的原核生物和与工业相关的光合生物进行同时评估（定量和与多样性相关）。自动化在线FCM与基于表型指纹识别的数据分析相结合，是用于定量和与多样性相关的种群动态监测的强大工具。定量数据评估表明，工程生态系统和自然生态系统中的原核生物生长阶段具有不同的生长速度和明显的峰值。基于表型指纹识别的与多样性相关的种群监测表明，混合培养中原核生物的激增受单一原核生物物种优势的支配。自动化在线FCM因其对多种表型分析的适应性以及与各种培养系统的兼容性，是微藻生物过程优化的强大工具。这有助于推进与微藻生物质和化合物生产相关的生物过程。因此，自动化在线FCM是一种可行的工具，可应用于基于单细胞价值链的生物基领域内的多个领域。
