Journal of Pharmaceutical Investigation Vol. 40, No. 6, 347-351 (2010) 347 Determination of Physicochemical Properties and Pharmacokinetic Profiles of Soybean Extracts Hyun-Chan Jung 1 , Sung-Kyun You 1,2 , SunKyu Kwon 3 , Ji-Sook Hwang 1 and Cheong-Weon Cho 1† 1 College of Pharmacy, Chungnam National University, 220 Gung-dong, Yuseong-gu, Daejeon 305-764, Korea 2 R&D Institute, Jeil Pharmaceutical Co., Ltd. 117-1 Keunkog-ri, Baekam-myun, Cheoin-gu, Yongin-si, Kyunggi-do 449-861, Korea 3 CornproductsKorea, Inc., 234-17, Maam-ri, Bubal-eup, Icheon-si, Gyeonggi-do, 467-863, Korea (Received September 20, 2010·Revised October 18, 2010·Accepted October 19, 2010) ABSTRACT - Isoflavones have received much attention because of their health-related and clinical benefits such as estro- genic 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 o 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 μg·h/mL, 3.045 μg·h/mL and 0.825 μg·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. Key words - Isoflavones, Soybean extracts, Pharmacokinetic, Physicochemical, Cell viability, Solubility Soybeans contain three types of isoflavones, as four chemical forms (aglycons, glycosides, acetylglucosides, and malonylglucosides) (Jian, 2009). The major aglycons are daidzein, genistein and glycitein. The major glycosides are genistin, daidzin and glycitin. The acetylglucosides include 6''- O-acetyldaiazin, 6''-O-acetylgenistin and 6''-O-acetylglycitin and the malonylglucosides contain 6''-O-malonyldaiazin, 6''-O- malonylgenistin and 6''-O-malonylglycitin (Vacek et al., 2008). 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. Particularly, genistein, one of the major isofla- vones in Leguminosae, has received great attention as a phy- toestrogen demonstrating pharmacological effects such as prevention of hormone-related cancers and bone loss (Zhang et al., 1999). Moreover, it is known that the bioavailability of isoflavones from soy-based foods and dietary supplements is a critical component in understanding possible beneficial and adverse effects in animal models and humans (Andrade et al., 2010). There is general agreement that absorption in the rodent and human gut proceeds by rapid release of aglycones through the action of bacterial and intestinal b-glucosidases following ingestion of isoflavone glucosides present in whole soy foods (Chang and Nair, 1995; Day et al., 2000; Hawksworth et al., 1971; Hosoda et al., 2008; Sfakianos et al., 1997). Therefore, many manufactures are controlling the final quantity and pro- file of isoflavones in soybean product by changing soy cultivar (Eldridge and Kwolek, 1983; Seguin et al., 2004), environ- mental conditions such as temperature, irrigation and atmo- spheric CO 2 (Eldridge and Kwolek, 1983; Kim et al., 2005; Rasolohery et al., 2008), processing (Aguiar et al., 2009; Gen- ovese et al., 2007; Wang et al., 1998; Yin et al., 2005) and stor- age (Huang and Chou, 2009; Lee et al., 2003). After oral administration of genistein with various doses (4, 2, 40 mg/kg) in rats, the bioavailability of genistein was 38.58, 24.34 and 30.75%, respectively. The T max , C max and AUC 0→∞ of genistein after oral administration of genistein (40 mg/kg), were 2 h, 4876.19 ng/mL and 31,269.66 ng·h/mL, respectively (Kwon et al., 2007). Also, there is a publication that the bio- availability of genistein and daidzein in a mouse model by comparing plasma pharmacokinetics of their aglycones and conjugated forms following administration of identical doses (1.2 mg/kg genistein and 0.55 mg/kg daidzein) by either an intravenous injection or gavage of the aglycones in 90% aque- ous solution vs a bolus administration of equimolar doses † Corresponding Author : Tel : +82-42-821-5934, E-mail : chocw@cnu.ac.kr DOI : 10.4333/KPS.2010.40.6.347