College of Agronomy, Northwest A&F University, Yangling, Shaanxi 712100, China.
Nanjing Forestry University, Nanjing 210037, China.
Ecotoxicol Environ Saf. 2018 Oct;161:648-654. doi: 10.1016/j.ecoenv.2018.06.037. Epub 2018 Jun 19.
Ionic liquids (ILs) are widely used in various chemical processes. However, a growing number of studies have found that ILs are potentially toxic to different types of living organisms, including crops. The present study analysed the effects of 1-butyl-3-methylimidazolium chloride ([Cmim]Cl) on the photosynthetic system and metabolism of maize seedlings. Results showed that [Cmim]Cl could significantly reduce maize leaf chlorophyll level and cause extensive leaf bleaching. The activity of photosystem II (PSII) was significantly inhibited when seedlings exposed to higher concentration of [Cmim]Cl. The maximum quantum yield of PSII and the potential efficiency of PSII were reduced by 63% and 88% under 800 mg/L [Cmim]Cl treatment in comparison with the control treatment. The RNA sequencing analysis performed to examine gene expression profiles of maize leaves under [Cmim]Cl treatment revealed 639 differentially expressed genes (DEGs), 115 of which were categorized into different metabolic pathways. Among these DEGs, the seven genes involved in the photosynthetic Calvin cycle were down-regulated by [Cmim]Cl exposure. For carbohydrates and amino acids metabolism, the genes for starch synthesis were down-regulated, while the genes for amino acids and protein degradation were up-regulated. The changes observed in these major metabolic pathways might be an important reason for [Cmim]Cl toxicity.
离子液体（ILs）在各种化学过程中被广泛应用。然而，越来越多的研究发现，ILs 对包括作物在内的不同类型的生物具有潜在毒性。本研究分析了 1-丁基-3-甲基咪唑氯（[Cmim]Cl）对玉米幼苗光合作用系统和代谢的影响。结果表明，[Cmim]Cl 可显著降低玉米叶片叶绿素水平，并导致叶片广泛白化。当幼苗暴露在较高浓度的 [Cmim]Cl 下时，光系统 II（PSII）的活性受到显著抑制。在 800mg/L [Cmim]Cl 处理下，PSII 的最大量子产量和 PSII 的潜在效率分别比对照处理降低了 63%和 88%。通过 RNA 测序分析研究 [Cmim]Cl 处理下玉米叶片的基因表达谱，发现 639 个差异表达基因（DEGs），其中 115 个基因被归类到不同的代谢途径中。在这些 DEGs 中，参与光合作用卡尔文循环的 7 个基因受到 [Cmim]Cl 暴露的下调。对于碳水化合物和氨基酸代谢，淀粉合成的基因被下调，而氨基酸和蛋白质降解的基因被上调。这些主要代谢途径的变化可能是 [Cmim]Cl 毒性的一个重要原因。
