title: Metabolite profiling and expression analysis of flavonoid, vitamin C and tocopherol biosynthesis genes in the antioxidant-rich sea buckthorn (Hippophae rhamnoides L.).
abstract: In this study, phenolic compounds were analyzed in developing berries of four Canadian grown sea buckthorn (Hippophae rhamnoides L.) cultivars ('RC-4', 'E6590', 'Chuyskaya' and 'Golden Rain') and in leaves of two of these cultivars. Among phenolic acids, p-coumaric acid was the highest in berries, while gallic acid was predominant in leaves. In the flavonoid class of compounds, myricetin/rutin, kaempferol, quercetin and isorhamnetin were detected in berries and leaves. Berries of the 'RC-4' cultivar had approximately ⩾ 2-fold higher levels of myricetin and quercetin at 17.5mg and 17.2 mg/100 g FW, respectively, than the other cultivars. The flavonoid content in leaves was considerably more than in berries with rutin and quercetin levels up to 135 mg and 105 mg/100 g FW, respectively. Orthologs of 15 flavonoid biosynthesis pathway genes were identified within the transcriptome of sea buckthorn mature seeds. Semi-quantitative RT-PCR analysis of these genes in developing berries indicated relatively higher expression of genes such as CHS, F3'H, DFR and LDOX in the 'RC-4' cultivar than in the 'Chuyskaya' cultivar. Vitamin C levels in ripened berries of the Canadian cultivars were on the high end of the concentration range reported for most other sea buckthorn cultivars. Orthologs of genes involved in vitamins C and E biosynthesis were also identified, expanding the genomic resources for this nutritionally important plant.
authors: Department of Biology, University of Western Ontario, London, ON, Canada. Electronic address: tfatima@uwo.ca.
authors: Tahira
authors: T
authors: Fatima
authors: Department of Biology, University of Western Ontario, London, ON, Canada. Electronic address: vigyakesari@gmail.com.
authors: Vigya
authors: V
authors: Kesari
authors: Department of Biology, University of Western Ontario, London, ON, Canada. Electronic address: iwatt@uwo.ca.
authors: Ian
authors: I
authors: Watt
authors: Departments of Computing Science and Biological Sciences, University of Alberta, Edmonton, AB, Canada. Electronic address: david.wishart@ualberta.ca.
authors: David
authors: D
authors: Wishart
authors: Ontario Ministry of Agriculture, Food and Rural Affairs, Simcoe Resource Centre, Simcoe, ON, Canada. Electronic address: jim.todd@ontario.ca.
authors: James F
authors: JF
authors: Todd
authors: Agroforestry Development Centre, Agriculture and Agri-Food Canada, Indian Head, SK, Canada. Electronic address: Bill.Schroeder@AGR.GC.CA.
authors: William R
authors: WR
authors: Schroeder
authors: Department of Plant Agriculture, University of Guelph, ON, Canada. Electronic address: gpaliyat@uofguelph.ca.
authors: Gopinadhan
authors: G
authors: Paliyath
authors: Department of Biology, University of Western Ontario, London, ON, Canada; School of Environmental & Rural Sciences, University of New England, Armidale, NSW, Australia. Electronic address: pkrishna@uwo.ca.
authors: Priti
authors: P
authors: Krishna
mesh_terms: D000975:Antioxidants / Q000032:analysis* / Q000737:chemistry; D001205:Ascorbic Acid / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid; D003373:Coumaric Acids; D005419:Flavonoids / Q000032:analysis / Q000378:metabolism; D005638:Fruit / Q000737:chemistry / Q000254:growth & development; D031281:Hippophae / Q000737:chemistry* / Q000254:growth & development; D019906:Nuclear Magnetic Resonance, Biomolecular; D010636:Phenols / Q000032:analysis; D018515:Plant Leaves / Q000737:chemistry; D016133:Polymerase Chain Reaction; D011422:Propionates; D011794:Quercetin / Q000031:analogs & derivatives; D024505:Tocopherols / Q000032:analysis*
chemical_list: D000975:Antioxidants; D003373:Coumaric Acids; D005419:Flavonoids; D010636:Phenols; D011422:Propionates; C047368:3-methylquercetin; C040015:myricetin; D011794:Quercetin; C495469:p-coumaric acid; D001205:Ascorbic Acid; D024505:Tocopherols
keywords: Elaeagnaceae; Flavonoids; Gene expression; Hippophae rhamnoides L.; Phenolic acids; Sea buckthorn; Tocopherol; Transcriptome; Vitamin C