title: Comparison of ozone and UV-C treatments on the postharvest stilbenoid monomer, dimer, and trimer induction in var. 'Superior' white table grapes.
abstract: Postharvest treatment of seedless white table grapes (var. 'Superior') with different gas ozone concentrations (3.88 and 1.67 g/h) for 1, 3, and 5 h induced an increase in stilbenoid biosynthesis [trans-resveratrol, piceatannol, and viniferinas (resveratrol dehydrodimers and dehydrotrimers)] during storage at 22 degrees C and 95% relative humidity. The maximal resveratrol concentration was reached after 2 days of storage, and this amount was similar to that induced by optimized UV-C treatments (1 min, 510 W, 40 cm). Although similar resveratrol concentrations accumulated in grapes after both UV-C and O3 treatments (maximum ozone production and time), the ozone treatment was more efficient in inducing viniferins accumulation in grape berries. A sequence in the biosynthesis of stilbenoids was observed, starting with the resveratrol monomer, continuing with the resveratrol dehydrodimers epsilon-viniferin and delta-viniferin, and ending with four different resveratrol dehydrotrimers. These trimers were different from alpha-viniferin, a trimer previously reported to be induced in grapes after biotic and abiotic stresses. Two alpha-viniferin isomers were also detected in the ozone-treated grapes, although at very low concentrations that prevented their quantification.
authors.affiliation: Research Group on Quality, Safety and Bioactivity of Plant Foods, Department of Food Science and Technology, CEBAS (CSIC), P.O. Box 164, Campus Universitario de Espinardo 30100 (Murcia), Spain.
authors.forename: Rocío
authors.initials: R
authors.lastname: González-Barrio
authors.forename: David
authors.initials: D
authors.lastname: Beltrán
authors.forename: Emma
authors.initials: E
authors.lastname: Cantos
authors.forename: María I
authors.initials: MI
authors.lastname: Gil
authors.forename: Juan Carlos
authors.initials: JC
authors.lastname: Espín
authors.forename: Francisco A
authors.initials: FA
authors.lastname: Tomás-Barberán
mesh_terms: D005638:Fruit / Q000187:drug effects / Q000378:metabolism* / Q000528:radiation effects; D010126:Ozone / Q000494:pharmacology*; D000077185:Resveratrol; D013267:Stilbenes / Q000737:chemistry* / Q000378:metabolism*; D014466:Ultraviolet Rays; D027843:Vitis / Q000378:metabolism*
chemical_list: D013267:Stilbenes; D010126:Ozone; C041525:3,3',4,5'-tetrahydroxystilbene; D000077185:Resveratrol