Plant Molecular Farming - Integration and Exploitation of Side Streams to Achieve Sustainable Biomanufacturing.

Johannes F Buyel

doi:10.3389/fpls.2018.01893

Abstract

Plants have unique advantages over other systems such as mammalian cells for the production of valuable small molecules and proteins. The benefits cited most often include safety due to the absence of replicating human pathogens, simplicity because sterility is not required during production, scalability due to the potential for open-field cultivation with transgenic plants, and the speed of transient expression potentially providing gram quantities of product in less than 4 weeks. Initially there were also significant drawbacks, such as the need to clarify feed streams with a high particle burden and the large quantities of host cell proteins, but efficient clarification is now readily achieved. Several additional advantages have also emerged reflecting the fact that plants are essentially biodegradable, single-use bioreactors. This article will focus on the exploitation of this concept for the production of biopharmaceutical proteins, thus improving overall process economics. Specifically, we will discuss the single-use properties of plants, the sustainability of the production platform, and the commercial potential of different biomass side streams. We find that incorporating these side streams through rational process integration has the potential to more than double the revenue that can currently be achieved using plant-based production systems.

Highlights

Reviewed by: Edward Rybicki, University of Cape Town, South Africa Alessandro Vitale, Italian National Research Council, Italy
The benefits cited most often include safety due to the absence of replicating human pathogens, simplicity because sterility is not required during production, scalability due to the potential for open-field cultivation with transgenic plants, and the speed of transient expression potentially providing gram quantities of product in less than 4 weeks
Inexpensive (∼0.002 € L−1), defined fertilizer solutions are sufficient for cultivation (Buyel and Fischer, 2012) as opposed to the expensive media required for mammalian cell cultures, which often cost more than 50 € L−1 (Xu et al, 2016)

Summary

Introduction

Reviewed by: Edward Rybicki, University of Cape Town, South Africa Alessandro Vitale, Italian National Research Council, Italy. We will provide details and examples for the sustainability of plant-based recombinant protein expression systems and the use of biomass side streams from such systems whereas, we will apply these thoughts to an existing production process for a recombinant mAb derived from plants to highlight the potential impact on process economics.

Results

Conclusion