Cell growth promoter and application thereof

A method for improving a cell viability, comprising the steps of

• preparing a Fe2+-ovalbumin (OVA) compound by adding a solution of OVA to a solution of Fe2+ and incubating at 37° C. for 15 minutes, wherein a molar ratio of the OVA to the Fe2+ is 1:0.5-4;
• diluting the Fe2+-OVA compound in cell culture medium, wherein a final concentration of Fe2+ added is 10-100 μM, and a final concentration of OVA added is 10-100 μM;
• and
• adding the cell culture medium containing the Fe2+-OVA compound to a mammalian cell, wherein
• the method is for non-diagnostic or non-therapeutic purposes.