Myristyltrimethylammonium bromide (MTAB) is a cationic surfactant used to improve biomass harvesting and pigment extraction form microalgae, but the mechanisms underlying its effectiveness are poorly defined. We document the mechanisms for enhanced harvesting and pigment extraction for the cyanobacterium Synechocystis sp. PCC 6803 using measurements from flow cytometer, zeta potential, release of soluble components, and microscopy. Harvesting efficiency increased as the MTAB/Biomass dose increased from 0 to 40%. A low MTAB dose (≤ 8%) mainly brought about coagulation and flocculation, which led to aggregation that improved harvesting, but 40% MTAB had the highest harvesting efficiency, 62%. Adding MTAB above a MTAB/Biomass dose of 8% also increased cell-membrane permeability, which allowed the solvent (ethyl acetate) to pass into the cells and resulted in a large increase in extraction efficiency of pigments: An MTAB/Biomass ratio of 60% for 180 min achieved the highest extraction efficiencies of chlorophyll and carotenoids, 95% and 91%, respectively. Combining harvesting and extraction performances with results from flow cytometry, zeta potential, release of soluble components, and microscopy lead to the following mechanistic understandings. MTAB dose from 8% to 40% solubilized EPS, which lowered the biomass's negative charge, but caused breakup of the large aggregates. An increase of cell permeability also in this stage allowed ethyl acetate to pass into the cells and achieve better pigment extraction. MTAB >40% led to cell lysis and a large increase in soluble organics, but complete cell lysis was not required to achieve the maximum extraction efficiency. The MTAB/Biomass % ratio for optimizing harvest efficiency and pigment extraction lay in the range of 40%–60%.

中文翻译：

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肉豆蔻基三甲基溴化铵如何增强集胞藻属物种的生物量收获和色素提取。PCC 6803

肉豆蔻基三甲基溴化铵（MTAB）是一种阳离子表面活性剂，用于改善微藻的生物量收集和色素提取，但是其有效性的机理尚不清楚。我们记录了蓝藻集胞藻增强收获和色素提取的机制sp。PCC 6803使用流式细胞仪，ζ电势，可溶性成分的释放和显微镜进行测量。随着MTAB /生物质剂量从0％增加到40％，收获效率提高。较低的MTAB剂量（≤8％）主要导致凝结和絮凝，从而导致聚集，从而改善了收成，但40％的MTAB收成效率最高，为62％。在MTAB /生物质剂量超过8％的情况下添加MTAB还可以提高细胞膜通透性，从而使溶剂（乙酸乙酯）进入细胞并导致色素的提取效率大大提高：MTAB /生物质比为60 180分钟的％的叶绿素和类胡萝卜素的提取效率最高，分别为95％和91％。将采集和提取性能与流式细胞仪，ζ电势，释放可溶成分，并通过显微镜检查得出以下机理的理解。MTAB的可溶EPS从8％增至40％，这降低了生物质的负电荷，但导致了大聚集体的分解。在此阶段，细胞通透性的增加也使乙酸乙酯能够进入细胞并获得更好的色素提取。MTAB> 40％导致细胞裂解，可溶性有机物大量增加，但是不需要完全的细胞裂解即可达到最大提取效率。用于优化收割效率和色素提取的MTAB /生物质％比在40％至60％的范围内。在此阶段，细胞通透性的增加也使乙酸乙酯能够进入细胞并获得更好的色素提取。MTAB> 40％导致细胞裂解，可溶性有机物大量增加，但是不需要完全的细胞裂解即可达到最大提取效率。用于优化收割效率和色素提取的MTAB /生物质％比在40％至60％的范围内。在此阶段，细胞通透性的增加也使乙酸乙酯能够进入细胞并获得更好的色素提取。MTAB> 40％导致细胞裂解，可溶性有机物大量增加，但是不需要完全的细胞裂解即可达到最大提取效率。用于优化收割效率和色素提取的MTAB /生物质％比在40％至60％的范围内。