Influence of phenolic acids on ion uptake: I. Inhibition of phosphate uptake

The influence of naturally occurring phenolic acids on phosphate uptake by barley (Hordeum vulgare L. cv. Karlsberg) roots was examined using ³²P-labeled phosphate. Without exception, all compounds tested, namely, benzoic, 2-hydroxybenzoic, 4-hydroxybenzoic, 3,4-dihydroxybenzoic, 3,4,5-trihydroxybenzoic, 4-hydroxy-3-methoxybenzoic, 4-hydroxy-3,5-dimethoxybenzoic, cinnamic, 2-hydroxycinnamic, 4-hydroxycinnamic, 3,4-dihydroxycinnamic, 4-hydroxy-3-methoxycinnamic, and 4-hydroxy-3,5-dimethoxycinnamic acids, inhibited uptake.