Melon-Up is standardized to L-Citrulline. Citrulline is considered a non-essential amino acid synthesized in the intestinal tract from Guanine. Gitrulline is a precursor to Arginine, it allows for increased and sustained Nitric Oxide production in the endthelium for support of circulatory function. Citrulline supports the body in optimizing blood flow through its conversion to L-Arginine and then nitric oxide. In addition Citrulline also increases energy, stimulates the immune system, and is essential for Urea Cycle unction as well.