Department of Medicinal Plants, Faculty of Agriculture and Natural Resources, Arak University, 38156-8-8349 Arak, Iran.
School of Earth and Environment M004, The University of Western Australia, Crawley, WA 6009, Australia.
Sci Total Environ. 2016 Nov 15;571:275-91. doi: 10.1016/j.scitotenv.2016.07.184. Epub 2016 Jul 30.
Engineered nanomaterials (ENMs) possess remarkable physicochemical characteristics suitable for different applications in medicine, pharmaceuticals, biotechnology, energy, cosmetics and electronics. Because of their ultrafine size and high surface reactivity, ENMs can enter plant cells and interact with intracellular structures and metabolic pathways which may produce toxicity or promote plant growth and development by diverse mechanisms. Depending on their type and concentration, ENMs can have positive or negative effects on photosynthesis, photochemical fluorescence and quantum yield as well as photosynthetic pigments status of the plants. Some studies have shown that ENMs can improve photosynthetic efficiency via increasing chlorophyll content and light absorption and also broadening the spectrum of captured light, suggesting that photosynthesis can be nano-engineered for harnessing more solar energy. Both up- and down-regulation of primary metabolites such as proteins and carbohydrates have been observed following exposure of plants to various ENMs. The potential capacity of ENMs for changing the rate of primary metabolites lies in their close relationship with activation and biosynthesis of the key enzymes. Several classes of secondary metabolites such as phenolics, flavonoids, and alkaloids have been shown to be induced (mostly accompanied by stress-related factors) in plants exposed to different ENMs, highlighting their great potential as elicitors to enhance both quantity and quality of biologically active secondary metabolites. Considering reports on both positive and negative effects of ENMs on plant metabolism, in-depth studies are warranted to figure out the most appropriate ENMs (type, size and optimal concentration) in order to achieve the desirable effect on specific metabolites in a given plant species. In this review, we summarize the studies performed on the impacts of ENMs on biosynthesis of plant primary and secondary metabolites and mention the research gaps that currently exist in this field.
工程纳米材料（ENMs）具有显著的物理化学特性，适用于医学、制药、生物技术、能源、化妆品和电子等不同领域的应用。由于其超小尺寸和高表面反应性，ENMs 可以进入植物细胞，并与细胞内结构和代谢途径相互作用，这可能通过多种机制产生毒性或促进植物的生长和发育。根据其类型和浓度的不同，ENMs 可以对植物的光合作用、光化学荧光和量子产率以及光合色素状态产生积极或消极的影响。一些研究表明，ENMs 可以通过增加叶绿素含量和光吸收以及拓宽捕获光的光谱来提高光合作用效率，这表明光合作用可以通过纳米技术来利用更多的太阳能。暴露于各种 ENMs 后，植物中的初级代谢物（如蛋白质和碳水化合物）的上调和下调都有观察到。ENMs 改变初级代谢物速率的潜在能力在于它们与关键酶的激活和生物合成密切相关。几类次级代谢物，如酚类、类黄酮和生物碱，已被证明在暴露于不同 ENMs 的植物中被诱导（主要伴随着与应激相关的因素），这突出了它们作为诱导子的巨大潜力，可以提高生物活性次级代谢物的数量和质量。考虑到 ENMs 对植物代谢的积极和消极影响的报告，有必要进行深入研究，以确定最合适的 ENMs（类型、大小和最佳浓度），以便在特定植物物种中对特定代谢物产生理想的效果。在这篇综述中，我们总结了关于 ENMs 对植物初级和次级代谢物生物合成影响的研究，并提到了该领域目前存在的研究空白。
