PLANT PHENOLICS AS REDUCTANTS FOR FERRITIN IRON RELEASE

Several plant phenols, including gallic acid, catechin, ferulic acid and p-coumaric acid are able to promote the reductive release of ferritin iron. The initial rate of Fe(III) reduction and release from horse spleen ferritin was quantified by spectrophotometric measurement of the ferrous-ferrozine complex at 562 nm. The relative order of reluctant reactivity was gallic acid > catechin > ferulic acid > p-coumaric acid. Superoxide ions or hydroxyl radicals are not likely to be involved in the reaction since superoxide dismutase and mannitol had no effect on the initial rate of iron release. This chemical reactivity may represent an important process in plant iron metabolism and represent a possible function for the presence of such phenolics in plant cells. © 1990.