Every year, the world loses about 654.38 billion+0 billion hectares of forest due to deforestation-an area equivalent to Iceland. At this rate, some scientists predict that the world's forests may disappear within 100 to 200 years.

So as to provide an environment-friendly and low-waste substitute. At the beginning of last year, MIT researchers cultivated a structure composed of woody plant cells in the laboratory, which hinted at the possibility of producing more effective biomaterials.

At that time, researchers said that it would take a lot of time to make a wooden table. Plant a tree, cut it down, transport it, grind it ... this is a process that lasts for decades. Luis Fernando Veracruz-Garcia, the chief scientist and senior author of the Microsystems Technology Laboratory at MIT, proposed a simpler solution: "If you want a table, you should grow a table."

And now. This research has been further deepened. Researchers at the Massachusetts Institute of Technology have created an adjustable technology that can generate wood-like plant materials in the laboratory, so that people can "plant" wood products similar to tables without cutting down trees and processing wood.

These researchers have proved that by adjusting some chemicals used in the growth process, they can precisely control the physical and mechanical properties of the obtained plant materials, such as stiffness and density.

They also said that using 3D bio-printing technology, plant materials with shapes, sizes and forms that do not exist in nature can be planted, and these plant materials are difficult to produce by traditional agricultural methods.

"Our idea is that you can plant these plant materials into the shape you need, so you don't need to do any material reduction afterwards, thus reducing energy and waste. There is great potential to expand it and develop it into a three-dimensional structure, "said Ashley Beckwith, the first author of this paper and a newly graduated doctoral student.

Although it is still in the early stage, this study shows that plant materials grown in the laboratory can be adjusted to have specific characteristics, which will one day enable researchers to grow wood products with the exact characteristics required for specific applications. For example, a high-strength material that is sufficient to support the walls of a house, or a specific thermal performance material that can heat a room more effectively. Luis Fernando velazquez-Garcia Luis Fernando velazquez-Garcia explained.

Jeffrey Boelens, a biomedical engineer and team leader of Charles Stark draper, wrote this paper together with Beckvis and Velaskes-Garcí a.. The research results were published in Today's Materials on May 25th.

To start planting plant materials in the laboratory, the researchers first isolated cells from the leaves of zinnia seedlings. Cells were cultured in liquid medium for two days and then transferred to gel medium containing nutrients and two different hormones.

In this process, by adjusting hormone levels, researchers can adjust the physical and mechanical properties of plant cells growing in nutrient-rich media.

"In the human body, your growth hormone determines how your cells develop and how certain characteristics are formed. Similarly, by changing the hormone concentration in nutrient solution, the reaction of plant cells is also different. Just by controlling these tiny chemical quantities, we can cause considerable changes in physical results, "Beckwith said.

Velaskes-Garcí a added that, to some extent, these growing plant cells behave almost like stem cells-researchers can give them some hints about what kind of cells they want to be.

They used a 3D printer to squeeze the cell culture gel solution into a Petri dish with a specific structure and let it incubate in the dark for three months. Velaskes-Garcí a said that even with this incubation period, this process is two orders of magnitude faster than the time required for a tree to grow to maturity. After hatching, the produced cell material will be dehydrated, and then the researchers will further evaluate its characteristics.

Researchers have found that lower hormone levels will produce rounder, more open and lower density cell plant materials. Higher hormone levels will lead to the growth of plant materials with smaller and denser cell structures. Higher hormone levels also produce harder plant materials. Researchers can plant plant materials with similar properties to some natural wood.

Another goal of this work is to study the lignification of plant materials grown in these laboratories. Lignin is a polymer deposited in plant cell wall, which makes plants rigid and woody. They found that the higher the hormone level in the growth medium, the more lignification will be caused, which will lead to more wood-like characteristics of plant materials.

Researchers have proved that using the 3D bioprinting process, plant materials can grow in customized shapes and sizes. This process does not use a mold, but uses a customizable computer-aided design file, which is sent to a 3D bio-printer to deposit the cell gel culture into a specific shape. For example, they can shape plants into the shape of small evergreen trees.

Borenstam said that this kind of research is relatively new. He added: "Using the technological progress originally developed for healthcare applications, this study proves that the technology between engineering and biology can meet environmental challenges."

The researchers also showed that cell cultures can survive and continue to grow for several months after printing, and using thicker gel to produce thicker plant material structure will not affect the survival rate of cells cultured in the laboratory.

"I think the real opportunity here is to optimize what you use and how to use it. If you want to create an object for a certain purpose, you need to consider the expectation of mechanical properties. This process is really suitable for customization. " Veracruz Garcia said.

Now that this technology has been proved to be effective and adjustable, researchers hope to continue experiments in order to better understand and control cell development. They also want to explore how other chemical and genetic factors guide cell growth.

Researchers want to evaluate how to transplant their methods to new species. Velaskes-Garcí a said that (Zinnia) does not produce wood, but if a commercially important tree species, such as pine, is produced in this way, it needs to be customized for this tree species.

Finally, he hopes that this work can help inspire other groups to study this field in depth to help reduce deforestation.

"Trees and forests are excellent tools to help us cope with climate change. Therefore, making use of these resources as much as possible for strategic planning will be the future social demand. " Beckwith added.

This research was partly funded by the De Lei Bai Scholar Program.