**Abstract**

The medicinal value of mushrooms is long known, but there is increasing awareness of their health benefits and interest in utilizing these in diet as food or nutritional supplement. In this chapter, we discuss the characteristics of 20 wild mushrooms and results from our work on their antioxidant activity, ability to promote nerve growth factor (NGF) synthesis and to convert the glycosylated forms of isoflavones to usable aglycon forms in soybeans fermented with their mycelia. Of the 20 mushroom types, we found that *Hericium ramosum* (*H. ramosum*) mycelia had higher antioxidant activity and showed greater capability for increasing the levels of aglycons, such as daidzein, glycitein, and genistein when used for fermentation of soybeans. In general, soybeans fermented with mushrooms increased the levels of aglycons compared to non-fermented ones. Taken together, all these results suggest that mushroom mycelia have a huge potential to be used as food and nutritional supplements for the health benefits they offer and present the prospects for utilizing them in soybean fermentation as natural resources for the large-scale production of aglycons.

**Keywords:** *H. ramosum* mycelia, antioxidant, NGF synthesis, soybean fermentation, isoflavone
