Isolation of hydroxycinnamoyltartaric acids from grape pomace by high-speed counter-current chromatography.
A method for the isolation of caftaric, coutaric and fertaric acids from grape pomace by high-speed counter-current chromatography (HSCCC) was developed. Using a system of hexane/ethyl acetate/methanol/water 3:7:3:7 (v/v/v/v) and 0.5% trifluoroacetic acid (TFA) in the head-to-tail elution mode, the target compounds were separated from co-extracted polyphenolics and subsequently isolated in a second run (tert-butyl-methyl ether/acetonitrile/n-butanol/water, 2:2:1:5 (v/v/v/v) and 0.5% TFA; tail-to-head elution mode). The concomitant flavonoid quercetin 3-glucuronide was also isolated with the present method. The compounds were characterized by 1H NMR spectroscopy, by LC/electrospray ionization (ESI)-MS/MS in the negative ionization mode, and by UV spectroscopy. A purity of 97.0% (2.0% Z-isomer) for caftaric acid, 97.2% (4.8% Z-isomer) for coutaric acid, and 90.4% (13% Z-isomer) for fertaric acid was obtained from 10 g of grape pomace with yields of 62, 48 and 23%, respectively. Caftaric and coutaric acids may be used for in vitro and in vivo studies and as reference substances for analytical purposes.
Maier
Thorsten
T
Institute of Food Technology, Section Plant Foodstuff Technology, Hohenheim University, August-von-Hartmann-Strasse 3, D-70599 Stuttgart, Germany.
Sanzenbacher
Solveigh
S
Kammerer
Dietmar R
DR
Berardini
Nicolai
N
Conrad
Jürgen
J
Beifuss
Uwe
U
Carle
Reinhold
R
Schieber
Andreas
A
D003377:Countercurrent Distribution / Q000379:methods*; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D010636:Phenols / Q000737:chemistry* / Q000302:isolation & purification*; D011794:Quercetin / Q000031:analogs & derivatives / Q000302:isolation & purification; D012997:Solvents / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization; D013056:Spectrophotometry, Ultraviolet; D027843:Vitis / Q000737:chemistry*
D010636:Phenols; D012997:Solvents; C515102:coutaric acid; C515103:fertaric acid; D011794:Quercetin; C515101:caftaric acid