With the aim of developing region specialized crops, this study was conducted to clarify effects of variant and cultivation region on antioxidative activities in various black soybean (Glycine max L.) seed tissues. Three black soybean varieties (SCEL-1, Wonheug, and Cheongja 3) were each cultivated in 4 different regions (Jeonju, Pyeongchang, Paju, and Cheonan). Harvested seeds were used to assess DPPH and ABTS radical scavenging activity, and total polyphenol, flavonoid and anthocyanin content. SCEL-1 soybean hull contained higher DPPH and ABTS radical scavenging activity (61% and 85% respectively) compared to Wonheug (40% and 50% respectively). SCEL-1 cultivated in Pyeongchang displayed the highest total polyphenol and flavonoid content (1,189 mg GAE/ 100g sample and 951 mg CTE/ 100g sample, respectively). Total anthocyanin content was ranked in the following order: SCEL-1>Wonheug>Cheongja 3. All black soybeans showed much higher antioxidant activity in the soybean hull than in the dehulled soybean. The antioxidant activity of black soybeans cultivated at high latitudes was high. These results suggest that the best black soybean variant for high beneficial biological activities is the SCEL-1 variant. For a complete understanding of the potential of black soybean as functional foods, we plan to further analyze their antioxidant activities in future studies.

The purpose of this study was to investigate the effects of envrionmental factors on the ecological responses, yield, and quality properties and physicochemical characteristics of yacon cultivated in various regions of Korea. Experiments were carried out in eight regions from 2010 to 2013. The temperature range in Jinbu, Bonghwa, Cheolwon, and Gangneung during the growth period of yacon cultivation was 17.5-24.6°C. The total yield and marketable yield of tuberous root in Jinbu were 4,065 and 3,196 kg/10a, respectively. The sugar content of yacon tuberous roots comprised 0.11-0.20% fructose, 0.11-0.37% glucose, 0.39-0.68% sucrose, 0.07-0.37% reducing sugar, and 7.03-9.62% fructo-oligosaccharides. The content of fructo-oligosaccharides, which is a functional substance, was the highest in yacon cultivated in Jinbu. Based on the productivity and functional fructo-oligosaccharides, the optimum areas to cultivate yacon are Jinbu and Bonghwa, which are located in the middle-highland zone (500-560 m) and have a suitable growth temperature of 18-25°C. The results of the present study indicate that temperature could be the factor with the greatest influence on the root growth of yacon.