Mitigation of As toxicity in wheat by exogenous application of hydroxamate siderophore of Aspergillus origin

Siderophores are secondary metabolites having molecular weight less than 10KD. They are specifically meant for chelation of ferric ions. They also tend to chelate metals under heavy metal stress, thus reducing their toxic effects. In the current study, experiments have been conducted on wheat plants to analyse siderophore's ability to counteract the adverse impact of arsenic (As) toxicity on physiology of plant seedlings along with biochemical response. As toxicity has been observed to adversely affect the lengths of root and shoot, chlorophyll and carotenoid contents, and activities of various antioxidative enzymes. The present study revealed that the application of hydroxamate-type siderophore isolated from Aspergillus nidulans under toxic condition significantly recovered the growth and helped in amending the enzymatic activities of superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD) of wheat genotype (NW1014). At the same time, injury caused by lipid peroxidation was significantly reduced. In silico studies revealed better binding affinity of ferricrocin-arsenate complex leading to thermodynamically stable complex. Encouraging results of As containment by organic biomolecule-siderophore can lead to an emerging bioremediation mechanism brimming with opportunities for agricultural field and environmental clean-up.