Effect of glucuronosylation on anthocyanin color stability.
The effect of glucuronosylation on the color stability of anthocyanins was investigated using glucuronosylated anthocyanins isolated from the flower petals of the red daisy (Bellis perennis) or obtained by enzymatic in vitro synthesis using heterologously expressed red daisy glucuronosyltransferase BpUGT94B1. Color stability toward light and heat stress was assessed by monitoring CIELAB color coordinates and stability at pH 7.0 by A(550). Cyanidin-3-O-2''-O-glucuronosylglucoside showed improved color stability in response to light compared to both cyanidin 3-O-glucoside and cyanidin 3-O-2''-O-diglucoside. A similar increase in color stability was not observed following heat treatment. Glucuronosylation did not increase the stability of anthocyanins at pH 7.0 as determined by A(550). To test for a possible effect of glucuronosylation on the color stability of anthocyanins in plant extracts used for food coloration, an elderberry (Sambucus nigra) extract was glucuronosylated in vitro. Glucuronosylation of approximately 50% of total anthocyanins proceeded fast and resulted in increased color stability in response to both heat and light. The data show that glucuronosylation may be used to stabilize industrially used extracts of natural colorants.
Osmani
Sarah Anne
SA
Department of Plant Biology and Biotechnology, University of Copenhagen, Copenhagen, Denmark.
Hansen
Esben Halkjaer
EH
Malien-Aubert
Céline
C
Olsen
Carl-Erik
CE
Bak
Søren
S
Møller
Birger Lindberg
BL
D000872:Anthocyanins / Q000737:chemistry* / Q000378:metabolism*; D019659:Asteraceae / Q000737:chemistry / Q000201:enzymology; D003116:Color; D004355:Drug Stability; D035264:Flowers / Q000737:chemistry / Q000201:enzymology; D005505:Food Coloring Agents / Q000737:chemistry; D014453:Glucuronosyltransferase / Q000235:genetics / Q000378:metabolism*; D006358:Hot Temperature; D008027:Light; D011994:Recombinant Proteins / Q000378:metabolism; D027923:Sambucus / Q000737:chemistry
D000872:Anthocyanins; D005505:Food Coloring Agents; D011994:Recombinant Proteins; D014453:Glucuronosyltransferase