Changes in the concentration, distribution, and speciation of arsenic in the hyperaccumulator Pteris vittata at different growth stages

Abstract

The arsenic (As) hyperaccumulator has become a model plant for the study of the interaction between plants and trace elements. However, the change in As concentration, distribution and speciation of hyperaccumulator Pteris vittata at different growth stages, especially with the aging process remains unknown. We collected P. vittata at different growth ages and analyzed As concentration, distribution, and speciation. Furthermore, metabolic profiling was conducted for P. vittata at different growth stages. With aging, the reduced glutathione/ oxidized glutathione ratio decreased while the malondialdehyde content increased, accompanied by the change in the main As speciation in P. vittata from arsenite to arsenate. Metabolic profiling also indicated significant difference in the compositions of metabolites during different growth stages. Specifically, flavonoid compounds were found to be positively correlated with As concentration. Results indicated that with the aging of P. vittata, the redox potential increased in the pinnae, leading to the oxidation of As, which may have impacted the distribution of As in this fern. Furthermore, the correlation between As concentration and flavonoid compounds implied the essential role of flavonoid metabolism in the accumulation and transport of As in this plant.