Contents 4 Flavonoid Biosynthesis

Schijlen EGWM, Ric de Vos CH, van Tunen AJ, Bovy AG (2004) Modification of flavonoid biosynthesis in crop plants. Phytochemistry 65 2631-2648 Schmeda-Hirschmann G, Jordan M, Gerth A, Wilken D, Hormazabal E, Tapia AA (2004) Secondary metabolite content in Fabiana imbricata plants and in vitro cultures. Z Naturforsch 59c 48-54... 

Although transgenic approaches have provided a very popular means to study metabolic control of flavonoid biosynthesis, nontransgenic approaches can prove equally powertul for developing tomatoes with altered flavonoid profiles. Of the many factors that may influence the polyphenol content of tomatoes, it is the genotype that is certainly one of the most relevant. Therefore, evaluation of flavonoid gene expression and polyphenol composition in the tomato germplasm can be the first usetul step on the successtul path to increase the quality of tomato fruit. 

The amount of flavonoids and flavanols in cocoa and chocolate might be highly variable and this variability is multifactorial. For example, plant s genetic predisposition dictates the biosynthesis of the primary (sugars, amino acids, etc.) and secondary metabolites (proanthocyanidins, saponins, alkaloids, etc.) while genetics can cause as much as a fourfold difference in flavan-3-ol content of fresh cocoa beans [22, 23]. Variability with respect to secondary metabolites exists between varieties (or cultivars) of the same species. However, various environmental factors determine the extent to which genetic potentialities are... 

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