J. H. LEE1, M. Renita2, Y. Vodovotz2, S. J. Schwartz2, and S. K. St. Martin3. (1) Dept. of Food Science & Technology, Seoul National Univ. of Technology, 172 Gongreung 2- Dong, Nowon-gu, Seoul, 139-743, South Korea, (2) Dept. of Food Science & Technology, Ohio State Univ., 2015 Fyffe Ct., 110 Parker Food Science Bldg., Columbus, OH 43210-1007, (3) Dept. of Horticulture & Crop Science, Ohio State Univ., 2021 Coffey Rd., 310-D Kottman Hall, Columbus, OH 43210
Consumptions of soybeans and soy products have been associated with reducing the risks of various cancers and inflammatory disease, which may be attributed, in part, to the presence of isoflavones. Researchers have postulated that the purported health benefit may be due to isoflavone estrogenic activity or perhaps antioxidant activity. Compared to Asian diets, the Western style diet is lacking in acceptable products containing large amounts of soy. One strategy to increase the consumption of soy is to incorporate soy-based ingredients into traditional products such as bread. The objectives of this study were to screen 17 Ohio soybean cultivars for their isoflavone content and antioxidant activities and thereby identify the soybean cultivars with high isoflavone content and/or high antioxidant activities for further processing into food ingredients of soy-based functional foods. Seventeen Ohio soybeans were screened for isoflavone content and antioxidant activity. Isoflavone content was determined by C18 reversed-phase high performance liquid chromatography (HPLC) coupled with a photodiode array detector. Antioxidant activities of soybean extracts were measured using 2,2-diphenyl-1-pycryl-hydrazil (DPPH) free radical and photochemiluminescence (PCL) methods. The highest and lowest total isoflavone content were 11.7 and 4.2 mmol/g soy, respectively, while the average was 7.1 mmol/g soy. Antioxidant activities of soybean extracts ranged from 7.5 to 12.1 mmol butylated hydroxytoluene (BHT) equivalent/g soy using the DPPH method. Lipid- and water-soluble antioxidant activities of soybean extracts ranged from 2.4 to 4.4 mmol Trolox equivalent/g soy and from 174.2 to 430.8 mmol ascorbic acid equivalent/g soy, respectively using PCL method. Five soybean cultivars were selected based on their high isoflavone content and/or high antioxidant activities. Those selected soybean cultivars, after further processing into food ingredients, may enhance the health benefits of soy containing foods.
Session 33F, Nutraceuticals & Functional Foods: Antioxidants and phytochemical analysis