Department of Biology, University of Padova, Via Basssi 58/B, 35131 Padova, Italy.
Department of Biology, University of Padova, Via Basssi 58/B, 35131 Padova, Italy.
Aquat Toxicol. 2024 Jul;272:106970. doi: 10.1016/j.aquatox.2024.106970. Epub 2024 May 21.
As well-known, microalgae have a pivotal role in aquatic environments, being the primary producer. In this study, we investigated the effects of Bisphenol A (BPA) analogues on cell ultrastructure, reactive oxygen species (ROS) production and photosynthetic pigment responses in the diatom Phaeodactylum tricornutum. Microalgae were exposed during both exponential and stationary growth phases to an environmental relevant concentration (300 ng/L) of three differing BPA analogues (BPAF, BPF, and BPS) and their mixture (100 ng/L of each compound). Bioaccumulation of such compounds in microalgae was also analysed. During the stationary growth phase, a significant increase in the percentage of cells with hydrogen peroxide production was recorded after exposure to both BPS and MIX. Conversely, no significant effects on total chlorophylls and carotenoids were observed. During exponential growth phase we observed that control cultures had chloroplasts with well-organized thylakoid membranes and a central pyrenoid. On the contrary, the culture cells treated with BPA analogues and MIX showed chloroplasts characterized by evident dilation of thylakoid membranes. The presence of degeneration areas in the cytoplasm was also recorded. During the stationary growth phase, control and culture cells were characterized by chloroplasts with a regular thylakoid system, whereas BPA analogues-exposed cells were characterized by a deep degradation of the cytoplasm but showed chloroplasts without evident alterations of the thylakoid system. Lipid bodies were visible in treated microalgae. Lastly, microalgae bioaccumulated mainly BPS and BPF, alone or in the MIX. Overall, results obtained revealed that BPA analogues can affect some important biochemical and ultrastructure features of microalgae, promoting ROS production. Lastly, the capability of microalgae to bioaccumulate bisphenols suggest a potential ecotoxicological risk for filter-feeders organisms.
众所周知，微藻在水生环境中起着关键作用，是主要的生产者。在这项研究中，我们研究了双酚 A（BPA）类似物对硅藻角毛藻细胞超微结构、活性氧（ROS）产生和光合色素响应的影响。在指数和静止生长阶段，微藻暴露于环境相关浓度（300ng/L）的三种不同 BPA 类似物（BPAF、BPF 和 BPS）及其混合物（每种化合物 100ng/L）中。还分析了这些化合物在微藻中的生物积累。在静止生长阶段，暴露于 BPS 和 MIX 后，过氧化氢产生的细胞百分比显著增加。相反，总叶绿素和类胡萝卜素没有显著影响。在指数生长阶段，我们观察到对照培养物的叶绿体具有组织良好的类囊体膜和中央淀粉核。相反，用 BPA 类似物和 MIX 处理的培养细胞显示出叶绿体的类囊体膜明显扩张。还记录到细胞质中退化区域的存在。在静止生长阶段，对照和培养细胞的叶绿体具有规则的类囊体系统，而暴露于 BPA 类似物的细胞的细胞质深度降解，但显示出叶绿体的类囊体系统没有明显改变。处理过的微藻中可见脂滴。最后，微藻主要积累 BPS 和 BPF，无论是单独存在还是在 MIX 中。总之，研究结果表明，BPA 类似物可以影响微藻的一些重要生化和超微结构特征，促进 ROS 的产生。最后，微藻积累双酚类物质的能力表明对滤食性生物具有潜在的生态毒理学风险。
