Science-Based Nutrition Dietary Supplement Vegan Non-GMO Gluten Free Helps Support Cardiovascular and Circulatory Health. Nattokinase is an enzyme derived from "natto", a traditional fermented soy food popular in Japan. During the natto production process, non-GMO soybeans are boiled and fermented with friendly Bacillus subtilis bacteria producing nattokinase. Doctor's Best Nattokinase contains nattokinase enzyme with Vitamin K2 removed. Nottokinase has been shown to support a healthy circulatory system by helping to maintain normal fibrinogen leaves in blood. Helps support a healthy circulatory system