The effects of allantoin, arginine and NaCl on thermal melting and aggregation of ribonuclease, bovine serum albumin and lysozyme

Ribonuclease showed no change in thermal stability and aggregation by the addition of allantoin. While allantoin showed no effects on the thermal stability of bovine serum albumin, it enhanced aggregation. Similarly, allantoin showed no stabilizing effects on lysozyme, but it strongly suppressed aggregation. Such suppressed aggregation resulted in reversibility of thermal unfolding of lysozyme. These effects of allantoin were then compared with those of NaCl and arginine hydrochloride. Arginine was similar to allantoin at low concentrations, where both solvent additives can be compared due to limited solubility of allantoin.