Meat grown in labs is on its way from laboratory curiosity to marketable product. Singapore in December became the first country to approve the sale of cultured meat, and several companies are planning to make their lab-meat products on large scale. The idea is to quickly produce meat without harming animals and possibly the climate.
So why stop at meat? Researchers at the Massachusetts Institute of Technology are now applying the concept to plants and trees. They have demonstrated a technique to grow plant-like tissues in the lab.
It’s an early proof-of-concept demonstration, but the team envisions a future in which you wouldn’t have to chop down trees or grow plants for years before using them for food, energy, consumer goods and infrastructure. “If you want a table, then you should just grow a table,” said Luis Fernando Velásquez-García, a scientist at MIT’s Microsystems Technology Laboratory in a press release.
Plant products are lauded as being renewable compared to their fossil fuel counterparts, says Ashley Beckwith, a mechanical engineer and lead author of the paper in the Journal of Cleaner Production. But producing biomaterials is an age-old process that involves growing whole plants, separating the small fraction of the harvested plant matter that is useful for food or materials, and throwing away or burning the leftovers.
Besides being inefficient, this process is constrained by climate, weather, and local resources. Plus, forestry and agriculture cause deforestation and biodiversity loss, and put pressure on environmental resources such as land and water while creating fertilizer and pesticide runoff.
Instead, growing plant tissue in laboratories uses “only resources we need to generate the materials we need,” she says. “Grown materials do not require access to farmable land and can be produced anywhere in the world, irrespective of climate and season, and require no harmful pesticides.”
The researchers grew wood-like plant tissue without soil or sunlight. They started by extracting live cells from the leaves of a Zinnia plant, and culturing them in a liquid growth medium. Then they transferred the cells to a 3D gel and added two plant hormones called auxin and cytokinin. By adjusting the levels of these hormones, the team coaxed the cells to produce lignin, the protein that gives plant tissue its rigidity and strength.
They could also make simple tweaks to the biochemical and mechanical properties of the gel scaffold to direct the cells to grow into certain types and produce plant material in customizable shapes. This could allow directly growing useful products without downstream processing, Beckwith says.
Lots more work needs to be done before lab-grown wood and plant fibers can be practical. The researchers are looking into ways to scale up the technique to produce larger quantities, and to translate it to higher-value plant species, she says. “We hope that one day these types of techniques could be used to help meet the growing demand for plant-based goods in ways that use our resources more strategically and don’t place the same burdens on the environment.”
Source: Ashley L. Beckwith, Jeffrey T.Borenstein, and Luis F. Velásquez-García. Tunable plant-based materials via in vitro cell culture using a Zinnia elegans model. Journal of Cleaner Production, 2021.