A group of Chinese researchers have managed to synthesise starch from carbon dioxide, more efficiently than nature. Scientists hope that creating the highly versatile material in industrial laboratories will save land and water, lessening the burden on traditional agriculture.
Researchers at the Tianjin Institute of Industrial Biotechnology, an affiliate of the Chinese Academy of Sciences, say their lab method could result in starch production 8.5 times faster than the natural starch synthesis cycle of corn, a common starch crop. Starch grains are the most abundantly available carbohydrate source in nature.
More than a foodstuff though, starch’s utility has been understood by humanity since the classical era. Described by the Roman philosopher, Pliny the Elder, as far back as 79AD, starch sees use in every industry including textiles, biofuel, alcohol, cooking and papermaking. Derived most commonly from crops like maize, wheat, potatoes and rice, starch production is expected to reach 160 million tons by 2026.
The research team’s synthesis method involves combining a chemoenzymatic system and an artificial starch anabolic pathway. This approach sees carbon dioxide undergoing a chemical transformation into methanol, by way of an organic catalyst. The methanol is then exposed to specialised enzymes and turned into sugars. These sugars are then put through a final process, creating polymeric starch.
From start to finish, the entire process turns carbon dioxide, a harmful greenhouse gas, into a wonder material and only uses 11 core reactions to do so. Comparatively, normal starch synthesis cycles involve around 60 biochemical reactions and are both land- and water-intensive.
Cai Tao, a scientist who worked on the project and lead author of the paper, ‘Cell-free chemoenzymatic starch synthesis from carbon dioxide’, said their team only needed a few hours to synthesise starch that in nature, would ordinarily take months. The chemical and atomic structure of the synthesised starch is the same as that created in nature, according to the team.
While the research is still in its infancy, many members of the scientific community are enthusiastic. Ma Yanhe, a co-author of the paper, said that if the cost of production for their new method can meet traditional agriculture, more than 90% of cultivated land and water resources could be saved.
Going beyond saving water and land, alleviating the burden on traditional starch production means fewer pesticides and fertilizers would be exposed to the soil.
Although the study was important, it required significant energy for production, said Hong Kong University of Science and Technology professor, Sun Fei. He said technological advancements in energy sources like fusion or new battery technologies could help the team realise their ambition.