Molecular Salts of l -Carnosine: Combining a Natural Antioxidant and Geroprotector with "generally Regarded as Safe" (GRAS) Organic Acids

The potent natural hydrophilic antioxidant l-carnosine has been reacted with a number of organic acids belonging to the "generally regarded as safe" (GRAS) group, resulting in the preparation of 11 new crystalline salts, which were characterized by X-ray powder diffraction and thermal analysis; the structures of six of them were determined from powder data, and one was fully characterized via single crystal data. The reaction with folic acid resulted in an amorphous folate salt, which was characterized by a combination of thermal methods and Raman spectroscopy; the solubility of the folate salt was also measured and found to be comparable to that of the commercial sodium folate.