Formation of Flower Fragrance Compounds from Their Precursors by Enzymic Action during Flower Opening.

Flower fragrance compounds were found to be produced from the precursor solution obtained from flower buds by crude enzyme prepared from the flowers at the opening stage. GC and GC-MS analyses showed the formation of volatile aroma constituents from the precursor solution of Jasminum polyanthum F, Jasminum sambac Ait, and Gardenia jasminoides E, but none in the case of Osmanthus fragrans L. The aroma-producing enzyme activity of G. jasminoides rapidly increased to reach the maximum at flower opening stage (stage 4) and decreased within 24 h after flower opening (stage 5). Fragrance precursors of G. jasminoides were suggested not to be mainly β-glucosides of linalool, eugenol, borneol, and isoeugenol based on the results after β-glucosidase and naringinase treatment of the precursor solution. The activity of hydrolytic enzyme(s) such as glycosidase was found to elevate during flower opening to result in the aroma formation.