Xiao Xiaolu, Wang Xiuping, Liu Lixin, Chen Chang, Sha Aihua, Li Jun
Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture and Rural Affairs, Oil Crops Research Institute, Chinese Academy of Agricultural Science, Wuhan 430062, China.
Analysis and Testing Center, Hebei Normal University of Science and Technology, Qinhuangdao 066000, China.
Ecotoxicol Environ Saf. 2022 Apr 1;234:113383. doi: 10.1016/j.ecoenv.2022.113383. Epub 2022 Mar 9.
The environmental safety and threats of graphene-based materials (GBMs) to the agroecosystem have attracted increasing attention in recent years. However, the mechanisms underlying the effects of GBMs on plants remain unclear. Here, we investigated the phytotoxicity of reduced graphene oxide (RGO), graphene oxide (GO) and amine-functionalized graphene (G-NH) on Brassica napus L. The results revealed that RGO impaired photosynthesis mainly by decreasing the chlorophyll content and Rubisco activity. A further gene-level analysis suggested that this effect of RGO might be due to its toxicity on sulfate transmembrane transporter and nitrogen metabolism, which ultimately led to nutrient imbalance. However, GO directly damaged the photosystem by disrupting the chloroplast structure, and a decrease in Rubisco activity indicated that GO also inhibits carbon fixation. Further gene-level analysis demonstrated that GO has toxicity on the chloroplast membrane, photosystem, photosynthethic electron transport and F-type ATPase. In addition, G-NH at 10-1000 mg L showed no significant toxicity. These findings shed light on the potential mechanism for the toxicity of GBMs on plants for risk assessment.
近年来，基于石墨烯的材料（GBMs）对农业生态系统的环境安全性及威胁已引起越来越多的关注。然而，GBMs对植物产生影响的潜在机制仍不清楚。在此，我们研究了还原氧化石墨烯（RGO）、氧化石墨烯（GO）和胺功能化石墨烯（G-NH）对甘蓝型油菜的植物毒性。结果显示，RGO主要通过降低叶绿素含量和核酮糖-1,5-二磷酸羧化酶（Rubisco）活性来损害光合作用。进一步的基因水平分析表明，RGO的这种作用可能归因于其对硫酸盐跨膜转运体和氮代谢的毒性，最终导致营养失衡。然而，GO通过破坏叶绿体结构直接损害光系统，Rubisco活性降低表明GO也抑制碳固定。进一步的基因水平分析证明，GO对叶绿体膜、光系统、光合电子传递和F型ATP酶具有毒性。此外，10-1000 mg/L的G-NH未表现出明显毒性。这些发现为GBMs对植物毒性的潜在机制提供了线索，以进行风险评估。
