Journal article
Grape skins (Vitis vinifera L.) catalyze the in vitro enzymatic hydroxylation of p-coumaric acid to caffeic acid
The ability of grape skins to catalyze in vitro conversion of p-coumaric acid to the more potent antioxidant caffeic acid was studied. Addition of different concentrations of p-coumaric to red grape skins (Cabernet Sauvignon) resulted in formation of caffeic acid. This caffeic acid formation (Y) correlated positively and linearly to p-coumaric acid consumption (X): Y = 0.5 X + 9.5; R 2 = 0.96, P <0.0001.
The kinetics of caffeic acid formation with time in response to initial p-coumaric acid levels and at different grape skin concentrations, indicated that the grape skins harboured an o-hydroxylation activity, proposedly a monophenol- or a flavonoid 3′-monooxygenase activity (EC 1.14.18.1 or EC 1.14.13.21).
The K m of this crude o-hydroxylation activity in the red grape skin was 0.5 mM with p-coumaric acid.
| Language: | English |
|---|---|
| Publisher: | Springer Netherlands |
| Year: | 2009 |
| Pages: | 1953-1960 |
| ISSN: | 15736776 and 01415492 |
| Types: | Journal article |
| DOI: | 10.1007/s10529-009-0103-5 |
| ORCIDs: | Meyer, Anne S. |
Antioxidant Applied Microbiology Biochemistry, general Biotechnology Caffeic Acids Coumaric Acids Cytochrome P-450 Enzyme System Flavonoid 3′-monooxygenase Hydroxylation Kinetics Life Sciences Microbiology Monophenol Monooxygenase Monophenol monooxygenase Ortho hydroxylation Plant Proteins Polyphenol oxidase Propionates Time Factors Vitis caffeic acid flavonoid 3'-hydroxylase p-coumaric acid
