title: Antioxidant capacity of polyphenolic extracts from leaves of Crataegus laevigata and Crataegus monogyna (Hawthorn) subjected to drought and cold stress.
abstract: Crataegus laevigata and Crataegus monogyna (hawthorn) were subjected to drought and cold stress treatments, and polyphenolic extracts from control and stress-treated plants were assayed for antioxidant capacities using a modified version of the Total Antioxidant Status Assay (Randox, San Francisco, CA). In addition, these plants were analyzed for levels of flavanol-type substance [(-)-epicatechin] and flavonoid (vitexin 2' '-O-rhamnoside, acetylvitexin 2' '-O-rhamnoside, and hyperoside) constituents that are important metabolites in hawthorn herbal preparations used to treat patients with heart disease. Drought and cold stress treatments caused increases in levels of (-)-epicatechin and hyperoside in both Crataegus species. Such treatments also enhanced the antioxidant capacity of the extracts. The results from this study thus indicate that these kinds of stress treatments can enhance the levels of important secondary metabolites and their total antioxidant capacities in leaves of Crataegus.
authors.affiliation: Department of Molecular Biology, University of Michigan, Ann Arbor, Michigan 48109-1048, USA.
authors.forename: Ara
authors.initials: A
authors.lastname: Kirakosyan
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Seymour
authors.forename: Peter B
authors.initials: PB
authors.lastname: Kaufman
authors.forename: Sara
authors.initials: S
authors.lastname: Warber
authors.forename: Steven
authors.initials: S
authors.lastname: Bolling
authors.forename: Soo Chul
authors.initials: SC
authors.lastname: Chang
mesh_terms: D000975:Antioxidants / Q000494:pharmacology*; D003080:Cold Temperature; D027825:Crataegus / Q000737:chemistry*; D005419:Flavonoids; D010636:Phenols / Q000494:pharmacology*; D010936:Plant Extracts / Q000494:pharmacology*; D018515:Plant Leaves / Q000737:chemistry; D011108:Polymers / Q000494:pharmacology*; D059808:Polyphenols; D014867:Water
chemical_list: D000975:Antioxidants; D005419:Flavonoids; D010636:Phenols; D010936:Plant Extracts; D011108:Polymers; D059808:Polyphenols; D014867:Water