Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials, College of Life Science and Technology, Jinan University, Guangzhou 510632, China.
Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials, College of Life Science and Technology, Jinan University, Guangzhou 510632, China.
J Hazard Mater. 2018 May 5;349:252-261. doi: 10.1016/j.jhazmat.2018.01.015. Epub 2018 Jan 9.
To investigate the mechanism of genotype differences in ciprofloxacin (CIP) accumulation, this study was designed to compare the tolerance and metabolic responses to CIP exposure between low (Cutai) and high (Sijiu) CIP-accumulation cultivars of Brassica parachinensis. Decreases in biomass and chlorophyll content were significantly greater (p < 0.05) and toxicities were more severe within cell ultrastructures of Cutai compared to Sijiu. A sequential growth test also revealed that Sijiu was more tolerant to CIP stress compared to Cutai. Meanwhile, significantly higher (p < 0.05) root parameters and higher areas of the stele and xylem may be responsible for the increased uptake and transport of CIP in Sijiu. Ultra performance liquid chromatography-electrospray ionization tandem mass spectrometry (UPLC-ESI-MS/MS) analysis revealed that CIP was metabolized to three major metabolites by the hydroxylation and breakdown of the piperazinyl substituent in the CIP molecule. The enhanced metabolic transformation of CIP in Sijiu indicated a more efficient capacity to detoxify, which in turn favored an increased accumulation of CIP in this cultivar. Thus, the present study demonstrated that the stronger tolerance and metabolism of Sijiu to CIP were responsible for its high CIP accumulation, suggesting an evolutionary mechanism for adaptation to environmental stress.
为了研究基因型差异在环丙沙星（CIP）积累中的作用机制，本研究旨在比较低（翠苔）和高（四九）积累型白菜型油菜对 CIP 暴露的耐受性和代谢反应。与四九相比，翠苔的生物量和叶绿素含量明显下降（p<0.05），细胞超微结构的毒性更严重。序贯生长试验也表明，与翠苔相比，四九对 CIP 胁迫更具耐受性。同时，根参数显著升高（p<0.05），中柱和木质部面积增大，可能是四九吸收和转运 CIP 增加的原因。超高效液相色谱-电喷雾串联质谱（UPLC-ESI-MS/MS）分析表明，CIP 被代谢为三种主要代谢物，通过 CIP 分子中哌嗪基取代基的羟化和断裂。四九对 CIP 的增强代谢转化表明其解毒能力更强，从而有利于该品种 CIP 的积累增加。因此，本研究表明，四九对 CIP 的较强耐受性和代谢能力是其高 CIP 积累的原因，这表明了一种适应环境胁迫的进化机制。
