Simonazzi Mara, Lemaire Sofia, Adamiano Alessio, Calvaresi Matteo, Cioffi Simona, Giorgio Francesca De, Giosia Matteo Di, Galletti Paola, Malferrari Marco, Papa Valentina, Pezzolesi Laura, Ruani Giampiero, Samorì Chiara
Department of Biological, Geological and Environmental Sciences (BiGeA), University of Bologna, Via Sant'Alberto 163, 48123 Ravenna, Italy.
Department of Chemistry "Giacomo Ciamician", University of Bologna, Via P. Gobetti 85, 40129 Bologna, Italy.
Bioresour Technol. 2025 Nov;435:132869. doi: 10.1016/j.biortech.2025.132869. Epub 2025 Jun 22.
Carbon nanomaterials such as single-walled carbon nanotubes (SWCNTs) can improve algal photosynthetic efficiency and increase the production of valuable compounds without decreasing biomass productivity. This work investigates the effects of SWCNTs dispersed by different proteins or functionalized with carboxylic groups (SWCNT-COOH) on several microalgae and a cyanobacterium, aiming to enhance photosynthetic performance and produce valuable compounds. The best SWCNTs' dispersion in water was achieved with lysozyme (LSZ@SWCNT), histone (HST@SWCNT) and SWCNT-COOH. In most cases, no toxicity was observed when the phototrophs were exposed for 72 h to these SWCNTs. The cyanobacterium Arthrospira platensis and the marine diatom Thalassiosira sp. were selected for evaluating the effects of exposure to LSZ@SWCNT for up to 14 days. Increased production of valuable algal compounds (i.e., phycocyanin + 38 % in A. platensis after 14 days, docosahexaenoic acid + 92 % and eicosapentaenoic acid + 63 % in Thalassiosira sp. after 7 days) was observed without any impairment of the photosynthetic efficiency (+19 % for Thalassiosira sp.). The effects observed on both the cell surface and intracellular structures (i.e., cell wall modifications, increased mucus, and vacuolization) suggested that the interaction with LSZ@SWCNT was responsible for the changes in biochemical composition and photosynthetic performance. Therefore, the proposed nanobiotechnological approach, which couples cyanobacteria and microalgae with SWCNTs, may tune the photosynthetic pathways towards the production of high-value compounds exploitable in cosmetics and nutraceuticals, ultimately improving the light-to-chemicals conversion processes without negatively impacting growth.
碳纳米材料，如单壁碳纳米管（SWCNTs），可以提高藻类的光合效率，并增加有价值化合物的产量，同时不降低生物量生产力。这项工作研究了由不同蛋白质分散或用羧基功能化的SWCNTs（SWCNT-COOH）对几种微藻和一种蓝细菌的影响，旨在提高光合性能并产生有价值的化合物。用溶菌酶（LSZ@SWCNT）、组蛋白（HST@SWCNT）和SWCNT-COOH实现了SWCNTs在水中的最佳分散。在大多数情况下，当光合生物暴露于这些SWCNTs 72小时时，未观察到毒性。选择蓝细菌钝顶螺旋藻和海洋硅藻Thalassiosira sp.来评估暴露于LSZ@SWCNT长达14天的影响。观察到有价值的藻类化合物产量增加（即钝顶螺旋藻在14天后藻蓝蛋白增加38%，Thalassiosira sp.在7天后二十二碳六烯酸增加92%，二十碳五烯酸增加63%），而光合效率没有任何损害（Thalassiosira sp.增加19%）。在细胞表面和细胞内结构上观察到的影响（即细胞壁修饰、黏液增加和液泡化）表明，与LSZ@SWCNT的相互作用是生化组成和光合性能变化的原因。因此，所提出的将蓝细菌和微藻与SWCNTs结合的纳米生物技术方法，可能会调整光合途径，以生产可用于化妆品和营养保健品的高价值化合物，最终改善光化学转化过程，而不会对生长产生负面影响。
