Doctor's Best Natto-Serra, Non-GMO, Vegan, Gluten Free, 90 Veggie Caps Best natto-serra is a combination of two naturally occurring proteolytic enzymes that have been researched for decades: serrapeptase (technically serratiopeptidase) and nattokinase. Proteolytic enzymes, as the term implies, break down proteins. Serrapeptase was first isolated from the non-pathogenic serratia bacteria species strain e15 by Japanese researchers in 1966. Serratia e15 was discovered in the Japanese silkworm, which uses its serrapeptase enzyme activity to break down its cocoon walls. The serrapeptase in this formulation is in a matrix with serrateric, a superior alternative to enteric coating. Serrateric protects the enzyme from inactivation by stomach acid, so that it can retain its activity until it reaches the intestine to become absorbed. Nattokinase was discovered in the 1980s when dr. HiroyUKi sumi studied 173 kinds of natural foods in an attempt to find a suitable protease enzyme to support circulatory health. From this systematic search his research group discovered that a traditional Japanese fermented "vegetable cheese" called natto yielded an enzyme with a potency matched by none of the other enzymes they found. They named it nattokinase. Natto has been a part of the Japanese diet for over 1,000 years and has been used traditionally against fatigue and for cardiovascular health maintenance. Features: Promotes and maintains healthy sinus and airway function Helps maintain blood pressure already in the normal range Supports healthy immune response and supports healthy circulation Gluten Free, Non-GMO, Vegetarian Label images may vary Contains Soy Product Details: Product Dimensions: 2.1 x 2.1 x 3.8 inches Shipping Weight: 0.8 ounces Domestic Shipping: Currently, item can be shipped only within the U.S. and to APO/FPO addresses. For APO/FPO shipments, please check with the manufacturer regarding warranty and support issues. International Shipping: This item is not eligible for international shipping. Learn More UPC: 753950002944 Item model number: DRB-00294