Colored soybean for cooking with rice have been used traditionally in Korea which is distinguished from other countries. Although many soybean cultivars have been developed for cooking with rice since the launch of the first cultivar Geomgeongkong1 in 1994, the breeding history of soybeans for cooking with rice is not quite long comparing to that of soybean paste/ bean curd and soy-sprout. In addition to developed cultivar, various landrace soybeans have still used for cooking with rice to Korean. This study was performed to select useful breeding materials and to evaluate the diversity of Korean landrace germplasms, especially black and/or green color seed coat soybeans. About five hundred eighty Korean colored soybean landraces were investigated for agricultural traits in experimental field and for DNA diversity using five SSR markers which showed high polymorphism between Korean soybean cultivars in a previous study. PowerCore (v. 1.0) software (http://genebank.rda.go.kr/PowerCore/) was used to analyze diversity of our landraces and to construct core set. In conclusion, we could obtain core set of forty-five germplasms by PowerCore analysis. Satt002 in analysed five SSR markers had twenty-two alleles and well represented diversity of black and/or green color germplasms.

NIR spectroscopy combined with multivariate analysis after the appropriate spectral data pre-treatment has been proved to be a very powerful tool for judgment of the relative pattern of the objects that have very similar properties. In this study, 500 GMO soybean seeds and, 500 non-GMO ones were measured in NIR reflectance mode. Principal component analysis (PCA), and discriminant analysis (DA) were applied to classify soybean with different genes into two groups (GMO and non-GMO). Calibrations were developed using DA regression with the cross-validation technique. The results show that differences between GMO and non-GMO soybeans do exist and excellent classification can be obtained after optimizing spectral pre-treatment. The raw spectra with DA model after the second derivative pre-treatment had the best satisfactory calibration and prediction abilities, with 97% accuracy. The results in the present study show NIR spectroscopy together with chemometrics techniques could be used to differentiate GMO soybean, which offers the benefit of avoiding time-consuming, costly and laborious chemical and sensory analysis.

Black soybeans, which have been widely utilized as food and as material for Oriental medicine, contain anthocyanins in the seed coat. Soybean seeds with black seed coat and green cotyledon are called “Seoritae” in Korea. Korean customer prefer “Seoritae” to normal black soybean with yellow cotyledon. The pigments contained in green cotyledon of black soybeans were chlorophylls and lutein. These constituents function as antioxidant and protect humans against diverse damages. The purpose of this study was to investigate the most suitable extraction condition and method of green cotyledon pigments in black soybeans. The green cotyledon pigments were analyzed on RP-HPLC with C18 column using gradient system. The gradient system was used two mobile phases. A gradient elution was performed with mobile phase A, consisting of 100% MeOH, and mobile phase B, consisting of 100% EtOAc. Among the 4 kinds of extraction method using methanol and/or acetone solution, ultrasonic extraction at 30 min. using acetone solution was most suitable extraction condition for simultaneous analysis of chlorophylls and lutein in soybean with green cotyledon.