Isoflavones have received much attention because of their health-related and clinical benefits such as estrogenic and anti-oxidative activities as well as triggering of natural killer cell activity. However, there are few publications reporting the pharmacokinetic profiles together with physicochemical properties of main isoflavones. Therefore, the pharmacokinetic parameters of main aglycones, daidzein, glycitein and genistein after oral administration of soybean extracts were investigated and the physicochemical properties of soybean extracts were characterized. It was observed that angle of repose was $46^{circ}$ and tap density, bulk density and porosity were 10.12, 4.3 and $0.86;g/cm^3$ and the mean $AUC_{last}$ of daidzein, glycitein and genistein was $11.376;{mu}g{cdot}h/mL$, $3.045;{mu}g{cdot}h/mL$ and $0.825;{mu}g{cdot}h/mL$, respectively. Cell viability was 60% at a concentration of 10 mg/mL. Taken together, it was suggested that isoflavones were contained in the soybean products and had an antioxidant activity and this study would be the basis to control the quality of soybean products and study of the bioequivalence between soybean products in future.