Production of medicinal soybean [Glycine max (L.) Merrill], characterized with black seed, white stripe at hilum border, yellow cotyledon and small seed, is increasing with increasing consumption. The objective of this study was to investigate the chemical composition of medicinal soybean seed and to provide basic information, for the characterization of these soybeans among genetic resources. Forty-four lines of medicinal soybeans collected from Korea and two control cultivars, 'Hwangkeumkong' (Yellow seed coat) and 'Geomjeongkong l' (Black seed coat) were planted at the Research Farm of the College of Natural Resources, Korea University, located at Namyangju City on May 25, 1996. Seeds of these lines were harvested at full maturity and analyzed for protein, oil, sugar, starch and mineral contents. Mean protein and oil content of the medicinal line seeds were 42.6 and 16.1%, respectively, and those of the control cultivars were in the middle range for protein and oil content. However, sugar and starch content of the medicinal line seeds appeared to be in the lower range of the distributions compared to the control cultivars and were 10.0 and 1.68%, respectively. Mean P, K, Ca, and Mg contents of the seeds of medicinal soybean lines were 15.9, 21.5, 3.11, and 2.81 mg/g, respectively, indicating that these lines had higher P, K, and Mg and lower Ca contents when compared to the control cultivars. Mean Na and Fe contents were 671 and 224 mg/kg, respectively, showing lower Na and similar Fe contents. The observed results provided that chemical compositions of medicinal soybean were, on average, different from those of the general soybean cultivars.

• Rak Chun Seong
• Jeong Gyu Kim
• Young Hyun Hwang