L-Citrulline Type: L-Amino Acids Application: Supplement & Nutrition | Pharmaceuticals chemical structure of kyowa citrullineL-Citrulline is an amino acid that plays an important role in nitric oxide metabolism and regulation.* L-Citrulline is converted to L-Arginine in the body to support L-Arginine and nitric oxide levels.* Increased production of nitric oxide (NO) promotes vascular dilation which improves oxygen and blood circulation throughout the body.* L-Citrulline is also expected to relieve muscle fatigue through ammonia elimination.* Antioxidant action and heart protection action are also known.