title: Oxidative stress and antioxidant responses to increasing concentrations of trivalent chromium in the Andean crop species Chenopodium quinoa Willd.
abstract: Quinoa (Chenopodium quinoa Willd), an ancient Andean seed crop, exhibits exceptional nutritional properties and resistance to abiotic stress. The species' tolerance to heavy metals has, however, not yet been investigated nor its ability to take up and translocate chromium (Cr). This study aimed to investigate the metabolic adjustments occurring upon exposure of quinoa to several concentrations (0.01-5mM) of CrCl3. Young hydroponically grown plants were used to evaluate Cr uptake, growth, oxidative stress, and other biochemical parameters three and/or seven days after treatment. Leaves accumulated the lowest amounts of Cr, while roots and stems accumulated the most at low and at high metal concentrations, respectively. Fresh weight and photosynthetic pigments were reduced only by the higher Cr(III) doses. Substantially increased lipid peroxidation, hydrogen peroxide, and proline levels were observed only with 5mM Cr(III). Except for a significant decrease at day 7 with 5mM Cr(III), total polyphenols and flavonoids maintained control levels in Cr(III)-treated plants, whereas antioxidant activity increased in a dose-dependent manner. Maximum polyamine accumulation was observed in 1mM CrCl3-treated plants. Even though α- and γ-tocopherols also showed enhanced levels only with the 1mM concentration, tyrosine aminotransferase (TAT, EC 2.6.1.5) activity increased under Cr(III) treatment in a dose- and time-dependent manner. Taken together, results suggest that polyamines, tocopherols, and TAT activity could contribute to tolerance to 1mM Cr(III), but not to the highest concentration that, instead, generated oxidative stress.
authors.affiliation: Dipartimento di Scienze Biomolecolari, Università di Urbino Carlo Bo, via Bramante 28, 61029 Urbino, Italy.
authors.forename: Valeria
authors.initials: V
authors.lastname: Scoccianti
authors.affiliation: Dipartimento di Scienze Biomolecolari, Università di Urbino Carlo Bo, via Bramante 28, 61029 Urbino, Italy.
authors.forename: Anahi E
authors.initials: AE
authors.lastname: Bucchini
authors.affiliation: Dipartimento di Scienze Biomolecolari, Università di Urbino Carlo Bo, via Bramante 28, 61029 Urbino, Italy.
authors.forename: Marta
authors.initials: M
authors.lastname: Iacobucci
authors.affiliation: Dipartimento BiGeA, Università di Bologna, via Irnerio 42, 40126 Bologna, Italy.
authors.forename: Karina B
authors.initials: KB
authors.lastname: Ruiz
authors.affiliation: Dipartimento BiGeA, Università di Bologna, via Irnerio 42, 40126 Bologna, Italy. Electronic address: stefania.biondi@unibo.it.
authors.forename: Stefania
authors.initials: S
authors.lastname: Biondi
mesh_terms: D000975:Antioxidants / Q000032:analysis*; D027465:Chenopodium quinoa / Q000187:drug effects* / Q000378:metabolism; D002857:Chromium / Q000633:toxicity*; D004305:Dose-Response Relationship, Drug; D005419:Flavonoids / Q000032:analysis / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000032:analysis; D015227:Lipid Peroxidation / Q000187:drug effects; D010084:Oxidation-Reduction; D018384:Oxidative Stress / Q000187:drug effects*; D010788:Photosynthesis / Q000187:drug effects; D018515:Plant Leaves / Q000378:metabolism; D018517:Plant Roots / Q000378:metabolism; D018547:Plant Stems / Q000378:metabolism; D011073:Polyamines / Q000032:analysis; D059808:Polyphenols / Q000032:analysis; D011392:Proline / Q000032:analysis; D012639:Seeds / Q000378:metabolism; D024505:Tocopherols / Q000032:analysis; D014444:Tyrosine Transaminase / Q000032:analysis
chemical_list: D000975:Antioxidants; D005419:Flavonoids; D011073:Polyamines; D059808:Polyphenols; D002857:Chromium; D011392:Proline; D006861:Hydrogen Peroxide; D014444:Tyrosine Transaminase; D024505:Tocopherols
keywords: Chenopodium quinoa; Chromium; Oxidative stress; Polyamines; Tocopherols; Tyrosine aminotransferase