title: Altered leaf colour is associated with increased superoxide-scavenging activity in aureusidin-producing transgenic plants.
abstract: The health-promoting property of diets rich in fruits and vegetables is based, in part, on the additive and synergistic effects of multiple antioxidants. In an attempt to further enhance food quality, we introduced into crops the capability to synthesize a yellow antioxidant, aureusidin, that is normally produced only by some ornamental plants. For this purpose, the snapdragon (Antirrhinum majus) chalcone 4'-O-glucosyltransferase (Am4'CGT) and aureusidin synthase (AmAs1) genes, which catalyse the synthesis of aureusidin from chalcone, were expressed in tobacco (Nicotiana tabacum) and lettuce (Lactuca sativa) plants that displayed a functionally active chalcone/flavanone biosynthetic pathway. Leaves of the resulting transgenic plants developed a yellow hue and displayed higher superoxide dismutase (SOD) inhibiting and oxygen radical absorbance capacity (ORAC) activities than control leaves. Our results suggest that the nutritional qualities of leafy vegetables can be enhanced through the introduction of aurone biosynthetic pathways.
authors.affiliation: JR Simplot Company, Simplot Plant Sciences, Boise, ID, USA.
authors.forename: Roshani
authors.initials: R
authors.lastname: Shakya
authors.forename: Jingsong
authors.initials: J
authors.lastname: Ye
authors.forename: Caius M
authors.initials: CM
authors.lastname: Rommens
mesh_terms: D000975:Antioxidants / Q000378:metabolism*; D032161:Antirrhinum / Q000235:genetics* / Q000378:metabolism; D001572:Benzofurans / Q000378:metabolism*; D047188:Chalcones / Q000378:metabolism; D003116:Color; D035264:Flowers / Q000378:metabolism; D018545:Lactuca; D006899:Mixed Function Oxygenases / Q000235:genetics / Q000378:metabolism*; D010858:Pigmentation; D018515:Plant Leaves / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D030821:Plants, Genetically Modified / Q000378:metabolism; D013482:Superoxide Dismutase / Q000378:metabolism; D014026:Nicotiana
chemical_list: D000975:Antioxidants; D001572:Benzofurans; D047188:Chalcones; D010940:Plant Proteins; C416232:aureusidin; D006899:Mixed Function Oxygenases; C416231:aureusidin synthase; D013482:Superoxide Dismutase