Effect of lactic fermentation on the total phenolic, saponin and phytic acid contents as well as anti-colon cancer cell proliferation activity of soymilk.

In an attempt to develop healthy dietary adjuncts, soymilk was fermented simultaneously with Streptococcus thermophilus 14085 and Bifidobacterium infantis 14603 at 37 °C for 24 h. It was found that lactic fermentation reduced the content of saponins and phytates, which possess antinutritional activity, and enhanced the total phenolic content as well as antitumor cell proliferation effect of soymilk against HT-29 and Caco-2 cells. The original antitumor cell component, starter organisms, and antitumor cell bioactive principles formed in soymilk during fermentation, might all have contributed to the enhanced antitumor activity of fermented soymilk. The antiproliferative effect of the extracts varied with extraction solvent. Extracts obtained from fermented soymilk with 80% methanol exhibited the highest suppression effect on the proliferation of HT-29 and Caco-2 cells. This study further stresses the potential of developing soymilk as a healthy dietary adjunct possessing enhanced anticancer activity through the use of lactic fermentation.