Iron fortification of plant biomass by overexpressing heterologous ferritin gene and the enhancement in biomass conversion

The recent development of incorporating ferrous ion to enhance the yields of dilute acid pretreatment of biomass is a promising technology for increasing the effectiveness and reducing the cost of pretreatment.  However, the current approach of adding iron ions into milled biomass prior to pretreatment is time-consuming and also may be compromised by the limitation of iron ion diffusion into the depth of plant biomass due to (1) the binding of iron ions to the surface of biomass, and (2) the existence of intra-cell wall air-filled void space.  Therefore, we propose to genetically manipulate plant for the purpose of accumulating iron in plant biomass.  This study demonstrated that overexpressing iron storage protein ferritin allowed the Arabidopsis plants accumulate iron during growth under both normal and iron fertilizer-spraying conditions.  Remarkably, the harvested biomass showed enhanced pre-treatability and digestibility.  Data also indicated that there is a positive correlation analysis between iron concentration and the pretreatability and digestibility of the biomass.