Ghariani Oumayma, Elleuch Jihen, Gargouri Bochra, Fakhfakh Faiza, Bisio Chiara, Fendri Imen, Guidotti Matteo, Abdelkafi Slim
Enzymatic Engineering and Microbiology Laboratory, Algae Biotechnology Unit, National Engineering School of Sfax, University of Sfax, Sfax, Tunisia.
CNR-SCITEC Istituto di Scienze e Tecnologie Chimiche "G. Natta", Via C. Golgi 19, Milan, Italy.
Int Microbiol. 2025 Feb 13. doi: 10.1007/s10123-025-00635-w.
Due to the variety of applications for nanomaterials (NMs) and ultrafine solids, their amounts released into the environment is constantly increasing, and their impact on ecosystems and organisms has led to remarkable problems. However, extensive studies on the effects of dispersed ultrafine inorganic metal oxides on algal growth at cellular and genomic levels still need to be performed. We assessed the potential toxicity of two commercial ultrafine inorganic metal oxides, silicon dioxide (SiO) and zinc oxide (ZnO), using the single-celled green microalgae Chlamydomonas sp. strain GO1 as a eukaryotic model. The cell response to commercial inorganic oxides was evaluated at physiological, biochemical, and molecular levels. An estimation of population growth inhibition levels was made. After 72 h of exposure, the IC of SiO and ZnO were 14.50 ± 2.98 mg/L and 56.80 ± 8.3 mg/L, respectively. Genotoxic effects of the studied materials were evaluated by acridine orange staining method and showed DNA fragmentation and morphological changes, including cell shrinkage and chromatin condensation on microalgae cells treated with both oxide materials. In addition, generated cytotoxic effects were evaluated. An inhibition of microalgae growth and a decrease in cell viability were observed. Antioxidant defense mechanisms, including enzymatic and non-enzymatic, were activated in response to materials exposure. We have also proven an overexpression of genes involved in carbohydrate biosynthesis and apoptosis. Infrared investigation suggested surface chemical interaction between algal cells and commercial ultrafine inorganic oxides.
由于纳米材料（NMs）和超细固体的应用种类繁多，它们向环境中的释放量不断增加，其对生态系统和生物体的影响已引发了显著问题。然而，关于分散的超细无机金属氧化物在细胞和基因组水平上对藻类生长影响的广泛研究仍有待开展。我们使用单细胞绿色微藻莱茵衣藻GO1菌株作为真核模型，评估了两种商业超细无机金属氧化物二氧化硅（SiO）和氧化锌（ZnO）的潜在毒性。在生理、生化和分子水平上评估了细胞对商业无机氧化物的反应。对种群生长抑制水平进行了估计。暴露72小时后，SiO和ZnO的半数抑制浓度（IC）分别为14.50±2.98毫克/升和56.80±8.3毫克/升。通过吖啶橙染色法评估了所研究材料的遗传毒性效应，结果显示在用两种氧化物材料处理的微藻细胞上出现了DNA片段化和形态变化，包括细胞收缩和染色质浓缩。此外，还评估了产生的细胞毒性效应。观察到微藻生长受到抑制且细胞活力下降。响应于材料暴露，包括酶促和非酶促的抗氧化防御机制被激活。我们还证实了参与碳水化合物生物合成和细胞凋亡的基因的过表达。红外研究表明藻类细胞与商业超细无机氧化物之间存在表面化学相互作用。
