Molecular effects of silver nanoparticles on Eruca sativa

Nanotechnology rapidly develops with applications in materials manufacturing, computer chips, medical diagnosis, energy and health care. As nanomaterials proliferation is a source of many different nanoparticles (NPs) for the environment, nanoecotoxicology is an emerging field of research. However, information on the ecotoxicology of engineered NPs is currently lacking. In particular, absorption, translocation, accumulation, and biotransformation of engineered nanoparticles in edible plants have not yet been studied. Classic toxicity tests using organism survival as the sole endpoint may overlook sublethal molecular effects which could have long-term ecological importance. For this reason, we used proteomic approach to analyse the potential toxicity of 10 nm polyvinyl-pirrolidon stabilised silver nanoparticles (AgNPs) on Eruca sativa. Data showed that, after seventy-two hours of treatments, roots exposed to 1, 10 and 20 ppm of AgNP accumulated silver. AgNP treatment appeared to stimulate Eruca sativa radical growth. Transmission electron microscopy examination showed that treated root cells were smaller and stubby. 2-DE protein profiles displayed significant changes in protein expression levels in 72 h AgNPstreated compared with control plants. These proteins belong to different functional categories such as HSPs, signaling proteins, metabolism, protein degradation, cell defense and rescue, binding and transport.