Dynamic changes of nutrients, isoflavone composition and antioxidant activities during liquid-state fermentation of soybean embryo homogenate by Ganoderma lucidum

This study aims to explore compositional changes of oligosaccharides, amino-type nitrogen, free amino acids volatile compounds, isoflavones, total phenol, total flavonoid, and antioxidant capacities during liquid-state fermentation (LSF) of soybean embryo homogenate (SEH) by <i>Ganoderma lucidum</i> to improve usability as functional food material. Raffinose and stachyose were <i>almost</i> completely hydrolyzed into monosaccharides such as fructose, glucose and galactose after 2 days of fermentation. After 5 days of fermentation, the contents of amino-type nitrogen and total free amino acids increased 7.0-fold and 2.4-fold, respectively, compared to the control group. Most of isoflavone glycosides were almost hydrolyzed into aglycones after 2 days and thereafter some of isoflavone aglycones were transformed into <i>ortho</i>-hydroxyisoflavones (OHIs). Total phenol, total flavonoid and antioxidants activities were significantly increased during the fermentation period. The result indicates that LSF of soybean embryo by <i>G. lucidum</i> can potentially improve acceptability and usability of soybean embryo as functional food material.