title: Plants as biofactories: physiological role of reactive oxygen species on the accumulation of phenolic antioxidants in carrot tissue under wounding and hyperoxia stress.
abstract: Plants subjected to postharvest abiotic stresses synthesize secondary metabolites with health-promoting properties. Here, we report the potential use of carrots (Daucus carota) as biofactories of caffeoylquinic acids when subjected to wounding and hyperoxia stresses. Wounding stress induced an increase of ∼287% in total phenolic content (PC) in carrots stored for 48 h at 20 °C. This increase was higher (∼349%) in the wounded tissue treated with hyperoxia stress. To further understand the physiological role of reactive oxygen species (ROS) as a signaling molecule for the stress-induced accumulation of phenolics in carrots, the respiration rate as well as the enzymatic activities of NADPH oxidase, superoxide dismutase, ascorbate peroxidase, and catalase were evaluated. Likewise, shredded carrots were treated with diphenyleneiodonium chloride solution to block NADPH oxidase ROS productions, and the phenylalanine ammonia lyase activity and total PC were evaluated. Results demonstrated that ROS play a key role as a signaling molecule for the stress-induced accumulation of PC in carrots.
authors.affiliation: Department of Horticultural Sciences, Texas A&M University , Vegetable & Fruit Improvement Center, College Station, Texas 77843-2133, USA.
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Jacobo-Velázquez
authors.forename: Ginés B
authors.initials: GB
authors.lastname: Martínez-Hernández
authors.forename: Silvia
authors.initials: S
authors.lastname: Del C Rodríguez
authors.forename: Cong-Mei
authors.initials: CM
authors.lastname: Cao
authors.forename: Luis
authors.initials: L
authors.lastname: Cisneros-Zevallos
mesh_terms: D000975:Antioxidants / Q000378:metabolism*; D018552:Daucus carota / Q000378:metabolism*; D018384:Oxidative Stress; D010100:Oxygen / Q000378:metabolism*; D010636:Phenols / Q000378:metabolism*; D010940:Plant Proteins / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism*
chemical_list: D000975:Antioxidants; D010636:Phenols; D010940:Plant Proteins; D017382:Reactive Oxygen Species; D010100:Oxygen