DESCRIZIONE
Disclosed are an anti-ice nucleation activator comprising a purine base or a purine base-containing polymer, and an antifreeze liquid comprising the anti-ice nucleation activator and water; a method for improving the anti-ice nucleation activity of a biological material, the method comprising bringing the anti-ice nucleation activator into contact with the biological material; and a method for preserving a biological material, the method comprising bringing the anti-ice nucleation activator into contact with a biological material.