Chemical Synthesis of Hydroxycinnamic Acid Glucosides and Evaluation of Their Ability To Stabilize Natural Colors via Anthocyanin Copigmentation
摘要:
This work describes the chemical synthesis of O-aryi-beta-D-glucosides and 1 -O-beta-D-glucosyl esters of hydroxycinnamic acids. In particular, OLaryl-beta-D-glucosides were efficiently prepared via a simple diastereoselective glycosylation procedure using phase transfer conditions. Despite the lability of its ester linkage, 1-O-beta-D-caffeoylglucose could also be obtained using a Lewis acid catalyzed glycosylation step and a set of protective groups that can be removed under neutral conditions. Hydroxycinnamic acid O-aryl-beta-D-glucosides were then quantitatively investigated for their affinity for the naturally occurring anthocyanin malvin (pigment). Formation of the pi-stacking molecular complexes (copigmentation) was characterized in terms of binding constants and enthalpy and entropy changes. The glucosyl moiety did not significantly alter these thermodynamic parameters, in line with a binding process solely involving the polyphenolic nuclei.
Malonated anthocyanins in malvaceae: Malonylmalvin from Malva sylvestris
作者:Kosaku Takeda、Shigeki Enoki、Jeffrey B. Harborne、John Eagles
DOI:10.1016/0031-9422(89)80040-8
日期:1989.1
Abstract A new anthocyanin, malvidin 3-(6″-malonylglucoside)-5-glucoside has been characterized in both wild and cultivated forms of Malvasylvestris. Thus the classic source of the anthocyanin, malvin, actually contains the pigment in the flowers in malonated form. Malonated anthocyanins were also detected in Althaea rosea, Lavatera olbia and a Sphaeralcea sp. but they were not present in five other
An orally ingestible composition comprising a coated spray-dried material comprising at least four anthocyanins, at least one of which is a monosaccharide and at least one of which is a disaccharide and a process for its production.
Molecular and biochemical characterization of the UDP-glucose: Anthocyanin 5-O-glucosyltransferase from Vitis amurensis
作者:Fei He、Wei-Kai Chen、Ke-Ji Yu、Xiang-Nan Ji、Chang-Qing Duan、Malcolm J. Reeves、Jun Wang
DOI:10.1016/j.phytochem.2015.06.023
日期:2015.9
Generally, red Vitis vinifera grapes only contain monoglucosidic anthocyanins, whereas most non-vinifera red grapes of the Vitis genus have both monoglucosidic and bis-glucosidic anthocyanins, the latter of which are believed to be more hydrophilic and more stable. Although previous studies have established the biosynthetic mechanism for formation of monoglucosidic anthocyanins, less attention has been paid to that of bis-glucosidic anthocyanins. In the present research, the full-length cDNA of UDP-glucose: anthocyanin 5-0-glucosyltransferase from Vitis amurensis Rupr. cv. 'Zuoshanyi' grape (Va5GT) was cloned. After acquisition and purification of recombinant Va5GT, its enzymatic parameters were systematically analyzed in vitro. Recombinant Va5GT used malvidin-3-O-glucoside as its optimum glycosidic acceptor when UDP-glucose was used as the glycosidic donor. Va5GT-GFP was found to be located in the cytoplasm by analyzing its subcellular localization with a laser-scanning confocal fluorescence microscope, and this result was coincident with its metabolic function of modifying anthocyanins in grape cells. Furthermore, the relationship between the transcriptional expression of Va5GT and the accumulation of anthocyanidin bis-glucosides during berry development suggested that Va5GT is a key enzyme in the biosynthesis of bis-glucosidic anthocyanins in V. amurensis grape berries. (C) 2015 Elsevier Ltd. All rights reserved.
PROCESS FOR THE PREPARATION OF ANTHOCYANIN-CONTAINING PRODUCTS