title: Cool-cultivated red leaf lettuce accumulates cyanidin-3-O-(6″-O-malonyl)-glucoside and caffeoylmalic acid.
abstract: Cultivating lettuce in greenhouses at low temperatures improves its CO2-balance and may increase its content of flavonoid glycosides and phenolic acids. We cultivated 5weeks old red leaf lettuce seedlings at 20/15°C (day/night) or 12/7°C until plants reached comparable growth stages: small heads were harvested after 13 (warm) and 26 (cool)days, while mature heads were harvested after 26 (warm) or 52 (cool)days. Additionally, some plants were cultivated first cool then warm and vice versa (39days). Cool-cultivated small heads had higher concentrations of cyanidin-3-O-(6″-O-malonyl)-glucoside and caffeoylmalic acid than warm-cultivated ones but we detected no differences concerning quercetin and luteolin glycosides or di-O-caffeoyltartaric and 5-O-caffeoylquinic acid. Regarding mature heads, there were only differences concerning cyanidin-3-O-(6″-O-malonyl)-glucoside. We therefore suggest that only cyanidin-3-O-(6″-O-malonyl)-glucoside was truly responsive to temperatures alone. Previously reported contrasting effects may rather be due to comparison of different growth stages or interactive effects with radiation.
authors.affiliation: Leibniz Institute of Vegetable and Ornamental Crops, Grossbeeren/Erfurt e.V., Theodor-Echtermeyer-Weg 1, 14979 Grossbeeren, Germany. Electronic address: becker@igzev.de.
authors.forename: Christine
authors.initials: C
authors.lastname: Becker
authors.forename: Hans-Peter
authors.initials: HP
authors.lastname: Klaering
authors.forename: Lothar W
authors.initials: LW
authors.lastname: Kroh
authors.forename: Angelika
authors.initials: A
authors.lastname: Krumbein
mesh_terms: D000872:Anthocyanins / Q000032:analysis* / Q000378:metabolism; D002109:Caffeic Acids / Q000032:analysis* / Q000378:metabolism; D003080:Cold Temperature; D005960:Glucosides / Q000032:analysis* / Q000378:metabolism; D018545:Lactuca / Q000737:chemistry / Q000254:growth & development* / Q000378:metabolism; D008293:Malates / Q000032:analysis* / Q000378:metabolism; D018515:Plant Leaves / Q000737:chemistry* / Q000254:growth & development / Q000378:metabolism
chemical_list: D000872:Anthocyanins; D002109:Caffeic Acids; D005960:Glucosides; D008293:Malates; C099798:caffeoylmalic acid; C462279:cyanidin-3-O-beta-glucopyranoside
keywords: Cyanidin; Flavonoid glycosides; Growth stage; Low temperature; Luteolin; Quercetin; Red leaf lettuce