Introduction Genistein is one of the isoflavones found in soy and soy products 1, 2. It has extraordinary advantages for its antioxidant 1 3 , anticancer 1, 2, 4 and estrogen effects 5, 6. Three hydroxyl groups in the aromatic rings of genistein contribute to its excellent antioxidant capacity 3. Moreover, genistein can inhibit the induction of stress proteins on tumor cells and retard the action of tyrosine kinase. This ultimately contributes to its anticarcinogenic benifits 4, 6. Genistein is also a kind of phytoestrogen contained in plants and is capable of showing estrogen effect. The structure of 17β-estradiol is similar to genistein therefore has the ability to bind to the estrogen receptor. Furthermore, genistein acts as a weak agonist or antagonist of estradiol depending its amount 5, 6. Despite having greater beneficial effects on the human body, genistein is hard to use because of its poor water-solubility 1. Therefore, it requires a novel solubilization treatment when genistein is intended to use in