Phytoestrogens biosynthesis

Phytoestrogens may also modulate the concentration of endogenous steroid hormones by binding to and inactivating the enzymes involved in their biosynthesis and metabolism. 

Leonard E, Chemler J, Lim KH, Koffas MA. 2006a. Expression of a soluble flavone synthase allows the biosynthesis of phytoestrogen derivatives in Escherichia coli. Appl Microbiol Biotechnol 70 85-91. 

Certain phytoestrogens have also been suggested to inhibit enzymes involved in estrogen biosynthesis and metabolism, as well as thyroid biosynthesis. Preliminary studies suggest they inhibit protein kinases and topoisomerases, as well as influence the cell cycle and subsequent proliferation, differentiation and apoptotic pathways. Interest in phytoestrogens, such as isoflavones, has increased since they are reported to exhibit some nonhormonal effects, such as antioxidation. 

Dinelli, G. et al.. Biosynthesis of polyphenol phytoestrogens in plants, in Phytoestrogens in Functional Foods, Yildiz, F., Ed., CRC Press, Boca Raton, FL, 2006, 19. 

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