Release of Ferulic Acid Esters From Barley Aleurone. I. Time Course of Gibberellic-Acid-Induced Release From Isolated Layers

Abstract

Removal of ferulic acid from barley aleurone cell walls is closely correlated with wall hydrolysis. The ferulic acid content of isolated aleurone layers (Hordeum vulgare L. cv. Himalaya) falls progressively during incubation with gibberellic acid (GA₃), to about one-third of the original content, by 72 h. At the same time an equivalent amount accumulates in the incubation medium, not as the free acid but still esterified to other components. The data show that there is no modification of the feruloyl group, or hydrolysis of the ester linkage prior to removal from the tissue, and therefore the GA₃-induced aleurone peroxidases and esterases are not directly involved.