Glyceollins: Soybean phytoalexins that exhibit a wide range of health-promoting effects

Glyceollins are phytoalexins produced by soy plants in response to stressful stimuli such as fungal infections, UV exposure or changes in temperature. Glyceollins have demonstrated anti-oestrogenic activity both in vitro in tumour cell lines and in animal models in vivo, suppressing oestrogen-responsive tumours through action at oestrogen receptors (ERs). More recent evidence suggests that glyceollins may also possess oestrogenic properties or may exhibit their effects through non ER-mediated mechanisms. In addition to antitumour effects, glyceollins possess antimicrobial and antioxidant activity, along with effects on glucose and lipid metabolism. This review also focuses on intestinal absorption, osteoinductive properties, and potential central nervous system effects of glyceollins. Further research is warranted to determine effective treatment doses, safety and possible side effects of long-term exposure to glyceollins in non-target tissues to realize the potential application of these compounds as dietary supplements or therapeutic agents.