Serrapeptase by Doctor's Best® is a protein-digesting enzyme, isolated from the friendly bacterium Serratia E-15 in Japanese silkworms. Serrapeptase has been used as a nutritional supplement in Europe and Asia for nearly three decades. Each vegetarian capsule is formulated with Serrateric™, an alternative to enteric coating designed for optimal absorption in the intestinal tract. Vegan, non-GMO and gluten free.