Isolation of hydroxycinnamoyltartaric acids from grape pomace by high-speed counter-current chromatography

Publication Type

Journal contribution

Authors

MAIER, T.H., SANZENBACHER, S., KAMMERER, D.R., BERARDINI, N., CONRAD, J., BEIFUSS, U., CARLE, R., SCHIEBER, A.

Year of publication

2006

Published in

Journal of Chromatography A

Band/Volume

1128/

Page (from - to)

61-67

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% (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.