title: Defence response of tomato seedlings to oxidative stress induced by phenolic compounds from dry olive mill residue.
abstract: ADOR is an aqueous extract obtained from the dry olive mill residue (DOR) which contains the majority of its soluble phenolic compounds, which are responsible for its phytotoxic properties. Some studies have shown that ADOR negatively affects seed germination. However, to date, few studies have been carried out on the effect of ADOR on the oxidative stress of the plant. It is well known that saprobe fungi can detoxify these phenolic compounds and reduce the potential negative effects of ADOR on plants. To gain a better understanding of the phytotoxic effects and oxidative stress caused by this residue, tomato seeds were germinated in the presence of ADOR, treated and untreated with Coriolopsis rigida, Trametes versicolor, Pycnoporus cinnabarinus and Penicillium chrysogenum-10 saprobe fungi. ADOR sharply reduced tomato seed germination and also generated high levels of malondialdehyde (MDA), O(2)(-) and H(2)O(2). However, bioremediated ADOR did not negatively affect germination and reduced MDA, O(2)(-) and H(2)O(2) content in different ways depending on the fungus used. In addition, the induced defense response was studied by analyzing the activity of both antioxidant enzymes (superoxide dismutase (SOD), catalase, ascorbate peroxidasa, glutathione reductase (GR), peroxidases and coniferil alcohol peroxidasa) and detoxification enzymes (glutathione-S-transferase (GST)). Our findings suggest that, because ADOR is capable of inducing oxidative stress, tomato seedlings trigger a defense response through SOD, GR, and GST activity and through antioxidant and lignification processes. On the other hand, the bioremediation of ADOR plays an important role in counteracting the oxidative stress induced by the untreated residue.
authors: Department of Soil Microbiology and Symbiotic Systems, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Prof. Albareda 1 Apdo. 419, E-18008 Granada, Spain.
authors: Mercedes
authors: M
authors: García-Sánchez
authors: Inmaculada
authors: I
authors: Garrido
authors: Ilda de Jesús
authors: Ide J
authors: Casimiro
authors: Pedro Joaquín
authors: PJ
authors: Casero
authors: Francisco
authors: F
authors: Espinosa
authors: Inmaculada
authors: I
authors: García-Romera
authors: Elisabet
authors: E
authors: Aranda
mesh_terms: D001673:Biodegradation, Environmental; D004798:Enzymes / Q000378:metabolism; D005658:Fungi / Q000187:drug effects / Q000378:metabolism; D018525:Germination / Q000187:drug effects; D006861:Hydrogen Peroxide / Q000378:metabolism; D018551:Solanum lycopersicum / Q000254:growth & development*; D008315:Malondialdehyde / Q000378:metabolism; D031658:Olea / Q000737:chemistry*; D018384:Oxidative Stress / Q000187:drug effects*; D010636:Phenols / Q000737:chemistry / Q000302:isolation & purification / Q000633:toxicity*; D036226:Seedlings / Q000187:drug effects / Q000378:metabolism; D026082:Singlet Oxygen / Q000378:metabolism; D014865:Waste Disposal, Fluid
chemical_list: D004798:Enzymes; D010636:Phenols; D026082:Singlet Oxygen; D008315:Malondialdehyde; D006861:Hydrogen Peroxide