Alfalfa, biomass yield

The two major leafy crops used for the production of recombinant proteins are tobacco and alfalfa, both of which have high leaf biomass yields in part because they can be cropped several times every year. The main limitation of such crops is that the harvested leaves tend to have a restricted shelf life. The recombinant proteins exist in an aqueous environment and are therefore relatively unstable, which can reduce product yields [16]. For proteins that must be extracted and purified, the leaves need to be dried or frozen for transport, or processed immediately after harvest at the production site. This adds considerably to the processing costs. 

FIGURE 14.3 Integrated biomass production-conversion system for growth and processing of alfalfa to yield high-protein animal feed supplement and electricity for the grid. From DeLong... 

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