抄録
Flowers emit floral scent compounds throughout the initial unfurling till the senescence stages. Floral scent compounds serve as attractants for species-specific pollinators. Recent progress in elucidating the biosynthetic pathways, enzymes, and genes involved in the formation of floral scent compounds allowed the determination of their physiology and function rigorously investigated at the molecular and biochemical levels. We investigated the biosynthesis and the emission of floral scent compounds in the flowers of roses and Osmanthus flowers. During the course of our research, we employed feeding experiments of stable isotopes and investigated the biosynthetic pathways based on the molecular biological methodologies. In this paper, 1) We describe the involvement of 2-phenylethylβ-D-glucopyranoside in the emission of 2-phenylethaol in rose flowers. 2) Moreover, we have elucidated that 2-pheylethanol emitted from rose flowers was synthesized from L-phenylalanine by the action of two enzymes, an aromatic amino acid-decarboxylase and a phenylacetaldehyde reductase. 3) We have also observed the seasonal change in the biosynthetic pathways of 2-phenylethanol in the roses. 4) Furthermore, we have characterized o-Methyl transferase as one of the key enzymes involved in the formation of floral scent methoxy-phenol in Chinese roses. 5) We have also confirmed that CCD1 was clarified to be involved in the synthesis and rhythmic emission of α-, β-ionones from carotenoids in Osmanthus flowers grown under the 12h light-12h dark conditions.
