Biogenesis of 2-Phenylethanol in Rose Flowers: Incorporation of [²H₈]L-Phenylalanine into 2-Phenylethanol and its β-D-…

Abstract

To clarify the biosynthetic pathway to 2-phenylethanol (2), the deuterium-labeled putative precursor, [²H₈]L-phenylalanine ([²H₈-1]), was fed to the flowers of Rosa ‘Hoh-Jun’ and R. damascena Mill. throughout maturation, ceasing feeding at the commencement of petal unfurling and at full bloom. Based on GC-MS analyses, [²H₈]-1 was incorporated into both 2 and 2-phenylethyl β-D-glucopyranoside (3) when the flowers were fed until full bloom, whereas no such incorporation into 2 was apparent when feeding was ceased earlier. In both species of rose, the labeling pattern for 2 was almost identical to that for 3, and indicated the presence of [²H₆]-, [²H₇]- and [²H₈]-2, and [²H₆]-, [²H₇]- and [²H₈]-3. This may be ascribed to the equilibrium between 2 and 3. The labeling pattern for 2 and 3 also indicated that these compounds were produced from 1 via several routes, the route involving phenylpyruvic acid being the major one.)

• rose flower
• scent formation
• biogenesis
• 2-phenylethanol
• 2-phenylethyl β-D-glucopyranoside)