58 エンバクのファイトアレキシン avenanthramide の二量化物の同定

抄録

Oats (Avena sativa L.) produce phytoalexin, avenanthramides, in response to elicitor treatment. Avenanthramides are a series of hydroxycinnamic acid amides with substituted anthranilic acids. It has been demonstrated that avenanthramides secreted into the elicitor solution are metabolized by peroxidase induced by elicitor treatment, and that a part of avenanthramides are incorporated into cell wall fraction, indicating the involvement of avenanthramides in the reinforcement of cell walls. It has also been shown that avenanthramides are converted to other compounds in the elicitor solution by experiments with radiolabeled avenanthramides. In the present study, we found the presence of a dehydrodimer (1) of avenanthramide B in the elicitor solution. The compound was also formed by a reaction of avenanthramide B with peroxidase from oat leaves. The chemical structure was identified using the enzymatically synthesized compound by spectroscopic analyses.