Wood is a renewable resource, but the total area of forests is rapidly shrinking. It takes decades to grow new ones. In addition, the production of lumber is quite costly: it requires water, land, fertilizers, plus handling and transportation costs.
Are there any alternatives? Let’s check thankfully to Knife magazine.
Scientists at the Massachusetts Institute of Technology have found a way to make this process more efficient and greener. They told Wired magazine how they had grown a wood-like fabric in the laboratory, which could potentially allow the creation of artificial wood and other plant materials in the future to reduce the harmful effects of agriculture and forestry on the environment.
You can read more about the results of this work in an article recently published in the Journal of Cleaner Production.
Ashley Beckwith, Mechanical Engineer and Lead Study Author, states: “If this method of producing plant materials becomes ubiquitous, it will help reduce the pressure on agricultural land, which in turn will save forests from deforestation.”
Previously, Beckwith was involved in medical research. But after the scientist visited an organic farm, she became interested in the issue of more efficient use of natural resources.
Growing plant materials in the laboratory does not require sunlight, soil or pesticides. And the production of only useful parts of plants will avoid unnecessary waste in the form of bark and leaves, which are formed in the process of traditional woodworking.
Luis Fernando Velazquez-Garcia, co-author of the study from the Laboratory of Microsystems Technology at MIT, writes: “The next goal is to produce materials where and when you need it. At the moment, there is a model in which materials are produced in just a few locations and then transported to the right place. “
To grow tissue in a test tube, cells are not used. For their experiment, the researchers extracted live cells from the leaves of dainty zinnia. The choice fell on this plant because it grows rapidly, and also because its cell differentiation – the process of changing cell functions – is well understood.
First, the cells were placed in the HRM broth for propagation, and then in the gel for further growth. “Over time, the cells began to grow and fill the gel scaffold, becoming the type of cells we wanted,” says Beckwith. The gel scaffold contains the nutrients and hormones needed to support cell growth.
However, the mixture of plant cells and gel cannot turn into a useful material without certain manipulations. Scientists have found out how changes in hormone concentration, gel acidity, cell density and other parameters affect the development and future characteristics of plant tissue. “Plant cells are very malleable. You can change their type to get the properties you want,” explains Velazquez-Garcia.
To obtain a wood-like material, the researchers selected vascular cells that carry water and minerals and ultimately produce a woody texture.
In the process of development, thanks to the polymer lignin, the cells formed a second, more solid cell wall. Using fluorescence microscopy, scientists could observe which of the cells became lignified (that is, turned into wood) and evaluate their characteristics.
3D bioprinting technology allows you to create the resulting material in almost any shape. The dark green fabric that the MIT researchers created is quite thick, but not firm enough for construction purposes.
Currently, the printed rectangular structures are only a few centimeters long, although larger models can be created.
The goal of this project using graceful zinnia cells is to prove that the technology for growing plant materials works. The next step is to apply it to other plant species from which stronger materials can be obtained. Such materials may be more expensive than natural materials at first, Beckwith said, but the ability to bypass the harvest, processing and production steps will reduce the cost over time.
The researchers speculate that in the future it will be possible to print finished products such as furniture, but even creating wooden blocks and beams will avoid the cost of cutting down trees and shaping the wood into the desired shape. Growing plant tissue in a laboratory will take about two months – much faster than waiting 20 years for a regular poplar to reach the required size.
Xuejun Pan, professor in the Department of Biosystems Engineering at the University of Wisconsin at Madison, states, “Growing hard enough wood is not the only interesting option. Plant materials can be used not only to create finished furniture, but also in production of fuels and chemicals. It is possible, for example, to produce biomass to be used as raw material for bioprocessing.”
According to Jeffrey Borenstein, one of the authors of the study from Charles Stark Draper’s lab, an experiment with organic printable material could be the basis for the creation of advanced thermoregulatory and self-healing materials and devices.
Plant cells respond to changes in the environment – empowering materials to transform industries.
“Material that grows, heals itself and interacts with the environment would be very valuable. The creation of materials from living cells allows these properties to be obtained, which was not possible before,” says Borenstein.
The possibilities of 3D bioprinting are still not well investigated, the researchers say, so it is likely that their experiment is the first of its kind. But even the noblest “green” aspirations must be judged soberly.
It sounds tempting to move away from deforestation, but it is difficult to predict how the lab-grown timber industry will evolve. For comparison, you can take laboratory made meat, which was created as an environmentally friendly alternative to natural meat, the production of which (primarily beef) causes significant harm to the environment. The artificial meat industry is already well developed, but it is still difficult to assess its contribution to the reduction of harmful emissions.
For example, replacing methane emissions from cattle with carbon dioxide emissions from energy production for growing artificial meat is a dubious gain. It is also unclear how much water is used to create ersatz meat compared to the amount of water used in herding.
Scaling up the production of plant materials in the laboratory also requires a better understanding of the factors that influence cell development, from hormone levels and acidity in the nutrient solution to mechanical forces within the helium scaffold and cell signaling. In short, there is still a lot of work to be done.
In addition, scientists may run into problems when trying to apply the techniques used to grow graceful zinnia cells to other plant species, Velazquez-Garcia said. “It takes a lot more resources to fully explore the possibilities of this technology,” he says.
But he’s sure that ecological solutions require bold ideas, and one day materials grown in a laboratory may surpass those created by nature.
