What Does Red Yeast Rice + Nattokinase Do?Jarrow Formulas Red Yeast Rice + Nattokinase is designed to support cardiovascular health and circulation. Jarrow Formulas Nattokinase is made via fermentation by Bacillus subtilis subsp. natto and then purified. Red Yeast Rice is fermented by the yeast Monascus purpureus. Jarrow Formulas uses Red Yeast Rice that is carefully fermented to avoid the presence of citrinin, a naturally-occurring mycotoxin. Each two capsules supply 2000 Fibrinolytic Units of activity from nattokinase to promote the breakdown (hydrolysis) of fibrin and��in conjunction with 1200 mg Red Yeast Rice extract�support healthy circulation.