Oxidative activity of some iron compounds on colon tissue homogenates from mice after administration of green tea, white tea and Pelargonium purpureum

We tested in mice the hypothesis that iron fortificants may exert oxidative activity on colon tissue homogenates (CTH), depending on the antioxidant capacity of infusions received with their diet. CTH were obtained from mice receiving daily by gavage 0.1 mL of infusion (8 g/100 mL water) from green tea or white tea or Pelargonium purpureum or catechin (0.01 g/100 mL) or water (control) for five days. All CTH had higher total antioxidant capacity than the control and lower susceptibility to oxidation induced by the retentates of in vitro digests of ferrous lactate, ferrous gluconate, ferrous sulfate and NaFeEDTA. Ferrous sulfate and NaFeEDTA exhibited higher oxidative effect on CTH than ferrous gluconate or ferrous lactate. These results are in support of our hypothesis and suggest that infusions received with diet may protect the colon from a potential oxidative effect of non-absorbed iron.