Advances in exploring equol production and application

The soybean isoflavone daidzein has been extensively studied. Equol represents the main active metabolite of daidzein in vivo. Due to its broadly biological activities, the preparation and characterization of equol have attracted a great deal of interest. In this review, the focus of attention is placed on the approaches to equol production, including the total synthesis of equol, equol from natural bacteria fermentation and synthetic biology for equol production. It is expected that the industrial production of equol with high yield could be realized in an economic way in the future. In addition, pharmacological activities and clinical applications of equol are also discussed to gain a systematically understanding as to the prospect of development for equol. Practical applications Equol is the main active metabolite of daidzein in vivo and considered to be the most active metabolite of the soybean isoflavones. It has broadly biological activities, including antitumor, antioxidative properties, cardiovascular protection, and relieve menopausal symptoms. However, only 25%–30% of young people can excrete equol in vivo when supplied with soy foods. So, it is necessary to develop efficient methods for equol preparation. Meanwhile, more systematic researches for the pharmacological activity of equol are also required. As mentioned above, this manuscript entitled "Advances in exploring Equol production and application," hoping that this review should draw widespread attention.