School of Chemical and Environmental Engineering, Shanghai Institute of Technology, Shanghai, 201418, China.
College of Environment, Zhejiang University of Technology, Hangzhou, 310032, China.
Environ Sci Pollut Res Int. 2020 May;27(14):16798-16805. doi: 10.1007/s11356-020-08253-x. Epub 2020 Mar 5.
The application of antibiotics is remarkable globally. However, antibiotic residues in aquatic ecosystems can pose adverse effects on nontarget plants and animals. In the present study, the cell growth properties and the production and release of microcystin-LR and microcystin-RR in cyanobacterium Microcystis aeruginosa after exposure to three typical antibiotics were investigated. Results showed that the order of the degree of chronic toxicities of the three chemicals was oxytetracycline hydrochloride (OTC) > tetracycline hydrochloride (TC) > chlortetracycline hydrochloride (CTC). The target antibiotics interfered with the production and release of the toxins microcystin-LR and microcystin-RR to varying degrees. TC simultaneously increased MC-LR intracellular and extracellular concentrations and interfered with MC-RR intracellular and extracellular concentrations to varying degrees. CTC reduced MC-LR intracellular concentrations and simultaneously reduced the MC-RR intracellular and extracellular concentrations. OTC increased the MC-LR intracellular and extracellular concentrations but did not have an effect on MC-RR concentrations. The extracellular MC-LR concentrations increased dramatically from day 24 to 27 when the cells were saturated, while most MC-RRs stayed within the cells. MC-LR can easily enter the surrounding water body and pose a threat when the water blooms occurred. Our results may help illustrate the influence of tetracycline antibiotics on the production and release of toxin in M. aeruginosa. It is important for environmental protection and evaluation. The results may as well guide the use of antibiotics in agricultural settings.
抗生素的应用在全球范围内都非常显著。然而，抗生素在水生生态系统中的残留会对非目标动植物产生不利影响。本研究考察了三种典型抗生素暴露后铜绿微囊藻中细胞生长特性以及微囊藻毒素-LR 和微囊藻毒素-RR 的产生和释放。结果表明，三种化学物质的慢性毒性程度顺序为盐酸土霉素（OTC）>盐酸四环素（TC）>盐酸金霉素（CTC）。目标抗生素对毒素微囊藻毒素-LR 和微囊藻毒素-RR 的产生和释放有不同程度的干扰。TC 同时增加了 MC-LR 的细胞内和细胞外浓度，并对 MC-RR 的细胞内和细胞外浓度有不同程度的干扰。CTC 降低了 MC-LR 的细胞内浓度，同时降低了 MC-RR 的细胞内和细胞外浓度。OTC 增加了 MC-LR 的细胞内和细胞外浓度，但对 MC-RR 浓度没有影响。当细胞达到饱和时，从第 24 天到第 27 天，细胞外的 MC-LR 浓度急剧增加，而大部分 MC-RRs 仍留在细胞内。当水华发生时，MC-LR 很容易进入周围水体，构成威胁。我们的研究结果可能有助于说明四环素类抗生素对铜绿微囊藻产生和释放毒素的影响。这对于环境保护和评估非常重要。研究结果还可以指导农业领域抗生素的使用。
