Main content area

Changes of phytochemical constituents (isoflavones, flavanols, and phenolic acids) during cheonggukjang soybeans fermentation using potential probiotics Bacillus subtilis CS90

Cho, Kye Man, Lee, Jin Hwan, Yun, Han Dae, Ahn, Byung Yong, Kim, Hoon, Seo, Weon Taek
Subtropical plant science 2011 v.24 no.3 pp. 402-410
Bacillus subtilis, biotransformation, fermentation, flavanols, foods, free radical scavengers, gallic acid, glycosides, isoflavones, probiotics, soybeans
A potential probiotics Bacillus subtilis CS90 was isolated from Korean soybean paste (doenjang). Biotransformation of phytochemical contents, isoflavones, flavanols, and phenolic acids, during the fermentation of soybean fermented food cheonggukjang by a potential probiotics B. subtilis CS90 was investigated. The levels of isoflavone aglycones, flavanols, and gallic acid increased, while the β-glucosidase and esterase activities, isoflavone glycosides (except for acetylglycosides), and flavanol gallates contents decreased. Total isoflavone content slightly decreased after 60h of fermentation, while total flavanol and phenolic acid content increased. The highest levels of daidzein (aglycone type) and acetyldaidzin (glycoside type) were recorded after 48h of fermentation. However, the total contents of glycosides, manolylglycosides, and flavanol-gallates decreased by about 80, 90, and 70% during 60h of fermenting cooked soybeans. In addition, the contents of total phenolic increased markedly from 253mg/kg to 9414mg/kg while the DPPH radical scavenging activity increased from 53.6 to 93.9% during this fermentation.