Changes of phenolic compounds in tomato associated with the heavy metal stress

Abstract

Heavy metals have restricted the plant regular life cycles affecting the plant primer and seconder metabolites by biochemical and physiological pathways. Phenolic compounds considered as products of metabolic alterations have been synthesized in various numbers and typical characteristic of plants. In this study, we aimed to investigate the variations of phenolic compounds with HPLC in leaves of tomato exposed to heavy metals. The applications of Cu, Cd and Pb significantly reduced the total phenolic content, levels of caffeic, chlorogenic and vanillic acids in all treated groups except for 50 and 20 ppm of Pb for total phenolics and vanillic acid, respectively. The level of benzoic acid is generally decreased by the application of heavy metals except for Cu at 50 ppm doses. Rutin is the most abundant phenolic compound in term of quantity among to analyzed phenolics and its content decreased depending on the heavy metal doses except for 10 ppm doses of Cd. The responses of tomato under heavy metals stress resulted in lower amount of phenolic compounds. In the present study, it was showed that total phenolic content has positive correlations with caffeic acid in all treatment of heavy metals.