Botany and Microbiology Department, Faculty of Science, Beni-Suef University, Beni-Suef, Egypt.
Doctoral School of Biology, Faculty of Science and Informatics, University of Szeged, Szeged, Hungary.
Int J Phytoremediation. 2024;26(12):1952-1969. doi: 10.1080/15226514.2024.2370022. Epub 2024 Jul 19.
Thallium (Tl), a key element in high-tech industries, is recognized as a priority pollutant by the US EPA and EC. Tl accumulation threatens aquatic ecosystems. Despite its toxicity, little is known about its impact on cyanobacteria. This study explores the biochemical mechanisms of Tl(I) toxicity in cyanobacteria, focusing on physiology, metabolism, oxidative damage, and antioxidant responses. To this end, and were exposed to 400 µg/L, and 800 µg/L of Tl(I) over seven days. showed superior Tl(I) accumulation with 7.8% removal at 400 µg/L and 9.5% at 800 µg/L, while removed 2.2% and 7.4%, respectively. Tl(I) exposure significantly reduced the photosynthesis rate and function, more than in . It also altered primary metabolism, increasing sugar levels and led to higher amino and fatty acids levels. While Tl(I) induced cellular damage in both species, was less affected. Both species enhanced their antioxidant defense systems, with showing a 175.6% increase in SOD levels under a high Tl(I) dose. This suggests that robust biosorption and antioxidant systems could be effective for Tl(I) removal. The study improves our understanding of Tl(I) toxicity, tolerance, and phycoremediation in cyanobacteria, aiding future bioremediation strategies.
铊（Tl）是高科技产业的关键元素，被美国环保署（EPA）和欧共体（EC）认定为优先污染物。铊的积累对水生态系统构成威胁。尽管铊具有毒性，但人们对其对蓝藻的影响知之甚少。本研究探讨了铊（I）对蓝藻毒性的生化机制，重点关注生理学、代谢、氧化损伤和抗氧化反应。为此， 和 分别暴露于 400µg/L 和 800µg/L 的 Tl（I）中七天。 表现出对 Tl（I）的优异积累能力，在 400µg/L 时去除率为 7.8%，在 800µg/L 时去除率为 9.5%，而 分别去除 2.2%和 7.4%。Tl（I）暴露显著降低了光合作用速率和功能， 在 中更为明显。它还改变了初级代谢，增加了糖的水平，并导致了更高的氨基酸和脂肪酸水平。虽然 Tl（I）在两种物种中都引起了细胞损伤，但 受影响较小。两种物种都增强了它们的抗氧化防御系统， 在高 Tl（I）剂量下 SOD 水平增加了 175.6%。这表明 具有强大的生物吸附和抗氧化系统，可有效去除 Tl（I）。该研究提高了我们对 Tl（I）毒性、耐受性和蓝藻生物修复的理解，有助于未来的生物修复策略。
