The stage of seed development influences iron bioavailability in pea (Pisum sativum L.)
Authors: Katie L Moore, Ildefonso Rodríguez-Ramiro, Eleanor R. Jones, Emily J. Jones, Jorge Rodríguez-Celma, Kirstie Halsey, Claire Domoney, Peter R Shewry, Susan Fairweather-Tait, Janneke Balk
Journal: Scientific Reports
Publication Date: 02 May, 2018
Garden peas are a good source of iron for our diets
Peas are naturally high in iron and may provide an important source of iron for human nutrition, especially as it may be more bioavailable than iron from other staple foods such as wheat. With growing pressure to consume less meat and the prevalence of iron-deficiency anaemia worldwide (including the UK), it is important to understand how crop plants accumulate iron and whether it is bioavailable.
Now, researchers have shown that iron in the form of ferritin accumulates gradually during pea seed development. Correlative immunolocalisation and NanoSIMS, undertaken at The University of Manchester, revealed with unprecedented detail that clusters of iron-loaded ferritin are located at the surface of starch grains throughout the bulk of the pea. NanoSIMS analysis indicates this iron is not colocalised with phosphorous-containing compounds such as phytic acid which could inhibit bioavailability.
Iron uptake studies using Caco-2 cells indicated that iron in microwaved immature peas was more bioavailable than boiled mature peas. This is mainly because there is less phytic acid present in immature peas than mature peas. This interdisciplinary study addresses many nutritional aspects related to the form of the iron, subcellular location and simulated digestion and indicates that immature peas, marketed as garden peas, can be further promoted as a source of bioavailable iron.
- NanoSIMS is a high spatial resolution secondary ion mass spectrometry instrument capable of mapping subcellular distributions of trace elements
- Caco-2 cells can be used as a model of the small intestine
- The iron storage protein ferritin forms clusters on the outside of starch grains in pea seeds