Tomato leaves in a circular economy: Molecular approaches to explore a new source of proteins

Summary

To help make food production more sustainable and reduce waste, my research looked at how to turn tomato leaves—a by-product of greenhouse farming—into a new source of plant-based protein. These tomato leaves can contain up to 27% protein, however, their extraction remains difficult. Therefore, I studied why such extraction is so difficult, and if breeding can help, to it. I identified that protein extraction yields decreased enormously along plant development. Such trend was linked to changes in the cell wall composition, protease activity, and a decline in soluble proteins along development. Additionally, protease genes were targeted by genetic engineering, leading to improved protein extraction, especially in younger leaves. The findings can help develop better tomato plants and farming methods that make it easier to use tomato leaves for protein, supporting a more circular and environmentally friendly food system.