The Effects of Environmental Arsenic on the Photosynthesis, Antioxidants Systems, and Biosynthesis of Pistachio Oil

Abstract Heavy metals adversely impact not only soil and water, but also the plants existing nearby. To investigate the impact of arsenic contamination on physiological properties, antioxidant activities, and synthesis of pistachio oil, an experiment was conducted in 2021 in a CRD. Findings proved that the amounts of arsenic in different organs, bioaccumulation coefficient (BCF), and transfer factor (TF) were different in different study areas. The amount of arsenic in roots was much higher than the leaves; the highest amount of arsenic in the leaves, roots, and fruits of the studied region was 1000 to 1200 mg/kg. The highest amounts of BCF found in the leaves and fruits were 0.11 and 0.015, respectively. The TF changes were found more frequent in pistachio leaves than its fruits. An increasing trend of changes was observed in ion losses, malondialdehyde, carotenoids and flavonoids, glutathione peroxidase activity, glutathione reductase, phenolalanine amoliase, pyrroline-5-carboxylase synthase, lipoxygenase, and linoleic fatty acid which was due to an increase in total concentrations of valretic acid. Chl a and b, protein content, reduced glutathione, ascarobate peroxidase, proline dihydrogenase, oil content, oleic acid, and palmitic acid decreased linearly. Changes to malondialdehyde, Chl a, flavonoids, and pyrroline-5-carboxylase synthase showed the highest correlations with changes in arsenic level. Generally, it was found that arsenic accumulation caused damage to the structure of proteins, cell membranes, and photosynthetic pigments of the plant. These damages, in turn, led to the activation of plant's defense mechanism and had deterrent impact on the biosynthesis of the plant's oil.