Oxidative Stress Biomarkers and Antioxidant Defense in Plants Exposed to Metallic Nanoparticles

Abstract

Environmental compartments are being enriched with myriads of nanoparticles (NPs) known for their unique physicochemical characteristics. Plants are sessile in nature and have greater chance to interact with environmental NPs. Oxidative stress, a condition of imbalance between the pace of reactive oxygen species (ROS) generation and its metabolism, is considered as one of undesirable consequences of NP-plant interaction. If not metabolized, ROS and its reaction products can bring irreparable changes in biomolecules and cellular organelles, disrupt the cellular redox homeostasis, and lead to cell death. In plant system, a synchronous action of enzymatic and nonenzymatic antioxidants metabolizes ROS and its reaction products and nullifies their potential consequences. Presenting an overview of the major metallic NPs, ROS-caused oxidative stress, its biomarkers, and antioxidant metabolism, this chapter highlights the modulation and role of major antioxidants in plants exposed to metallic NPs and offers tips for thought in the future.