What is Nattokinase? Nattō is a traditional Japanese food made from fermented soybeans. Natto has been known for centuries for its positive medicinal properties, particularly for cardiovascular disorders. To make Nattō, soybeans are fermented with the beneficial bacteria Bacillus  natto (sometimes listed as Bacillus subtilis natto). During fermentation, the Bacilli produce enzymatic peptidases, the most important of which is nattokinase. Like other proteases, nattokinase has potent anti-inflammatory activity, as well as several other beneficial properties, including fibrinolytic activity.  Researcher Hiroyuki Sumi, identified the active enzyme in natto and demonstrated its ability to dissolve vascular blood clots.  He called this enzyme “nattokinase”-meaning “enzyme in natto.”