Recent interest in green tea polyphenols has increased owing to their antioxidant activities and their possible role in the prevention of cancer and cardiovascular diseases. Typically, 93% compounds of total polyphenols in green tea leaves, many of which are called catechins, are flavonoids. The major tea catechins are a mixture of epicatechin isomers, including (-)-epigallocatechin gallate (EGCG), (-)-epigallocatechin (EGC), (-)-epicatechin gallate (ECG), and (-)-epicatechin (EC). Separation of green tea catechins is generally carried out by HPLC-UVD. UV detector is a suitable detector for quantification this class of molecules and allows high sensitivity level for polyunsaturated species. However, UV detection does not discriminate different compounds having similar chromophore groups. More detailed structural information can be collected when a mass spectrometer is coupled with a UV-DAD. MSD is a powerful tool for qualitative analysis to identify and confirm molecular structures of unknown compounds, and it is particularly useful for quantitative analysis, owing to its high sensitivity and selectivity. This study describes the application of HPLC-DAD/MS methods for the rapid and routine analysis of 9 catechins in green tea leaves. Green tea extracts were injected directly onto a reversed phase HPLC column. Compounds, identified on the basis of their absorbance and MS spectrum, included gallic acid, (-)-epicatechin, and their various gallate derivatives. HPLC/MS detection was found to be more sensitive than UV-DAD, and MSD showed good precisions for quantification of catechins.
Anthocyanin pigments in black soybean seed coat have been known as including biological activities, which are antitumor, antioxdant and antivirus. Also in soybean, isoflavone have been reported as health-promoting benefits, which are antiestrogen, antioxidant, antitumoral activities and preventing cardiovascular diseases and osteoporosis. The consumption of soybean increased in Korea because of the importance of its functional characteristics of the anthocyanin and isoflavone. Therefore, this experiment was conducted to investigate the variation of anthocyanin, and isoflavone contents in Korean domestic black soybean cultivars grown at different latitudinal locations, Suwon (37°16'N) and Milyang (35°30'N). D3G, C3G, and total anthocyanins in Geomjeongkong # 3, C3G, and total anthocyanins in Ilpumgeomjeongkong grown at higher latitudinal Suwon were higher compared to lower latitudinal Milyang. Daidzein, glycitein, genistein, and total isoflavone contents in Gemjeongkong # 4 were highest among the seven cultivars. Daidzein contents in Gemjeongkong # 3, Milyang # 112, and Milyang # 113 grown at higher latitudinal Suwon were higher compared to lower latitudinal Milyang. Glycitein contents in Gemjeongkong # 3, and # 4 grown at higher latitudinal Suwon were higher Milyang while that in Milyang # 113 grown at lower latitudinal Milyang was higher compared to higher latitudinal Suwon. Genistein contents in most black soybean cultivars except Milyang # 113, and total isoflavone contents in Gemjeongkong # 4 and Cheongjakong grown at lower latitudinal Milyang were higher compared to higher latitudinal Suwon. The variations of anthocyanin except Pt3G and isoflavone contents seemed to be affected by environmental conditions like different latitude than the genotype because they showed the significant interaction between cultivars and locations.
Crude protein is about 40% in soybean seed, and oil extracted from soybean seeds is one of the major vegetable oils. Also soybean oil is a good source of essential fatty acids, and sugars in soybean seed is composed of water-soluble saccharides, and most of them are oligosaccharide namely sucrose, raffinose, and stachyose. Although the production of soybean decreased in Korea, the consumption of soybean increased in recent time because soybean is well known as a well-being and healthy food. Therefore, this experiment was conducted to know the variation of crude protein, crude oil, fatty acids, and sugar contents in Korean domestic black soybean cultivars grown at different latitudinal locations, Suwon (37°16'N) and Milyang (35°30'N). In most black soybean cultivars, oleic acid content was higher, while linoleic acid, or linolenic acid contents were lower at higher latitudinal Suwon compared to lower latitudinal Milyang. Sucrose content in Geomjeongkong # 3, raffinose contents in Gemjeongkongkong # 3, # 4, Ilpumgeomjeongkong, and Cheongjakong, and stachyose content in Gemjeongkong # 1 grown at lower latitudinal Milyang was higher compared to higher latitudinal Suwon. The variations of crude protein, crude oil and fatty acids contents seemed to be affected by genotype than growing locations according to different latitude as they did not show the significant interaction between cultivars and locations. In contrast, the variations of glucose, sucrose, and stachyose contents maybe affected by environmental condition as different latitude than the genotype because they showed the significant interaction between cultivars and locations.