MOSSBAUER STUDY OF IRON IN SOYBEAN HULLS AND COTYLEDONS

Oxidation states of iron in hulls and cotyledons separated from immatu re and mature soybean seeds were studied by Mossbauer spectroscopy. It was found that iron in immature and mature hulls was exclusively in a trivalent high-spin state and that iron in immature and mature cotyle dons was in both trivalent high-spin and divalent high-spin states, th e former being dominant. Upon treatment of the hulls and cotyledons wi th 2 mol dm(-3) hydrochloric acid, ferric ions were found to be gradua lly reduced to ferrous ions, giving an identical isomer shift and quad rupole splitting. These characteristics are close to those of ferrous ions coordinated octahedrally with six water molecules.