Heme iron polypeptide polymer with high iron content as an ideal iron supplement

Iron deficiency is a common nutritional problem and results in anemia in human population. Heme iron (HI) is known to be a better iron supplement than non-HI because of its fewer gastrointestinal side effects. HI polypeptide (HIP) is prepared by enzymatic digestion of hemoglobin from animal blood and subsequent ultrafiltration or dialysis. Here we find a polymerized form of HIP with high iron content and provide an efficient method to prepare the HIP polymer. The molecular weight of the HIP polymer was around 250 kDa, which was determined by gel filtration. The polymer was soluble in a wide range of pH, and iron content was about 1.8%, that is the highest among any other forms of HIP. Moreover, when administered to healthy human, the polymer increased serum iron level twofold, 5 h after the administration. These data indicate that the HIP polymer containing high level of iron can be used as an ideal iron supplement in anemic patients.