Vanilla planifolia Andrews: In Vitro Biosynthesis of Vanillin and Other Phenylpropanoid Derivatives

Abstract

The tropical orchid Vanilla planifolia is mainly known for the aromatic flavor of its cured fruits. Today, V. planifolia represents an important crop in several tropical countries, where it is propagated by cuttings and cultivated in large plantations. The cured beans and other natural vanilla products are important spices and flavors on the world market. Although vanillin, the main flavor component of the cured vanilla beans, can be produced synthetically from wood lignin, the natural flavor is far superior due to the presence of many other minor, but important constituents. Vanillin and other vanilla flavor compounds are biosynthesized in the aging vanilla bean through the phenylpropanoid metabolism. Several steps in the biosynthesis of these so-called C6-C1-compounds (benzoic derivatives), such as vanillin and 4-hydroxybenzaldehyde, are at the present still unclear.