Equol: a Phytoestrogen from Soy Bean: Its Roles in Health

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Thanannat Meemak
Jureerut Daduang
Patcharee Boonsiri


Equol is a phytoestrogen with similar chemical structure and estrogen-like effect. It is synthesized from soy bean in food by specific metabolic pathway using bacteria in  human intestine. Daidzein, a precursor, is changed to S-(-)equol, which can bind to b-estrogen receptor. However, this metabolic pathway is found in some people because there are several factors involved in this synthesis, for example, type, amount of intestinal bacteria and behavior of soy-bean consumption. There are many reports about using equol in treatment of menopause, some cancer including breast cancer, prostate cancer, cardiovascular disease and osteoporosis. At present, there are many research groups study about equol and its role in health, which may be applied in medicine. 


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Meemak, T., Daduang, J., & Boonsiri, P. (2016). Equol: a Phytoestrogen from Soy Bean: Its Roles in Health. Ramathibodi Medical Journal, 39(2), 132–141. Retrieved from https://he02.tci-thaijo.org/index.php/ramajournal/article/view/57629
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