China Chemical Industry News: How many steps are required to artificially synthesize starch from carbon dioxide?

On September 23, the Chinese Academy of Sciences held a press conference announcing that the Tianjin Institute of Industrial Biotechnology under the Academy had made breakthrough progress in the artificial synthesis of starch, achieving for the first time in the world the de novo synthesis of starch from carbon dioxide. The relevant findings were published online on the 24th Beijing time in the internationally renowned academic journal Science. Currently, starch is primarily produced by crops such as corn through natural photosynthesis, with its synthesis and accumulation involving around 60 metabolic reactions as well as complex physiological regulatory mechanisms; the theoretical energy conversion efficiency is only about 2%. Cropping usually requires a long period of time, and it utilizes large amounts of land, freshwater, as well as agricultural inputs such as fertilizers and pesticides. A research team from the Tianjin Institute of Industrial Biology, Chinese Academy of Sciences, used a method similar to building with blocks to design from scratch a new pathway for the non-natural fixation of carbon dioxide and the artificial synthesis of starch, involving 11 key reaction steps; they achieved the full synthesis of starch molecules from carbon dioxide in the laboratory for the first time. Tests such as nuclear magnetic resonance have shown that the structural composition of artificially synthesized starch molecules is identical to that of natural starch molecules. The Tianjin Institute of Industrial Biology, in collaboration with the Dalian Institute of Chemical Physics of the Chinese Academy of Sciences, uses chemical catalysts to reduce high-concentration carbon dioxide into carbons compounds under the action of high-density hydrogen energy. New enzymes for carbons polymerization are then designed and developed; these enzymes enable the polymerization of carbons compounds into terpenes compounds based on the principles of chemical glycosylation reactions. Finally, through biological optimization, these terpenes compounds are polymerized into hexoses compounds, which are further used to synthesize linear and branched starches.

Is it edible? Is it still used in industry?

When reporting on official news from sources such as CCTV, special attention should be paid to relevant figures and key terms. For example, in the process of China’s first successful synthesis of starch, there are several points that are particularly noteworthy: 1. China’s method for synthesizing starch reduced the number of steps required, cutting from over 60 steps to just 11 – it is a new technology, and there is a significant gap between this technology and others ； 2. Energy utilization is increased by 3.5 times, overcoming the limitations imposed by photosynthesis on the use of solar energy. The starch production in 1 cubic meter of bioreactor over one year is equivalent to the average annual yield of 5 mu of corn in China – this reduces China’s reliance on land for food production ； 3. This technology can be integrated with efforts to achieve the \"dual carbon\" goals – carbon dioxide can be used to produce starch, thereby reducing greenhouse gas emissions and helping China meet its carbon emission targets ； 4. China is trying to achieve large-scale industrial production of it—we need to realize large-scale use of this technology.

Under normal circumstances, starch is primarily synthesized by green plants through photosynthesis, by fixing carbon dioxide. In crops, during the complex process of converting carbon dioxide into starch, the theoretical efficiency of utilizing solar energy is no more than 2%; moreover, the growth cycle of crops is long, requiring large amounts of land, fresh water, fertilizers, and other resources. Therefore, the new starch preparation method enables efficient conversion and utilization of carbon dioxide, which is undoubtedly a great advantage. On September 23, the Chinese Academy of Sciences held a press conference to provide a detailed introduction and explanation of this technology for artificially synthesizing starch from carbon dioxide. At the meeting, Zhou Qi, vice president of the Chinese Academy of Sciences, said that the world today faces a series of major challenges such as global climate change, food security, shortages of energy and resources, and environmental pollution. The conversion and utilization of carbon dioxide, as well as the synthesis in the food starch industry, are among the key scientific and technological issues needed to address these challenges. The overall design approach of the team is to separate the high-concentration carbon dioxide emitted by thermal power plants and cement factories as a raw material, convert low-density solar energy into high-density electricity or hydrogen energy as a source of power, form simple hydrocarbons, and then develop a biosynthetic process to convert these hydrocarbons into starch. This research achievement has also been recognized and highly praised by experts from both China and abroad. Reviewers in Science stated, “This work represents a milestone breakthrough that will have a transformative impact on next-generation biomanufacturing and agricultural production.” ”Jens Nielsen, an academic of the U.S. National Academy of Engineering and professor at Chalmers University of Technology in Sweden, said that the successful conversion of methanol produced through the chemical catalysis of carbon dioxide into starch using a recombinase system composed of different types of enzymes is a remarkable example of the integration of modern catalytic chemistry and synthetic biology. Ouyang Pingkai, an academician of the Chinese Academy of Engineering and former president of Nanjing Tech University, also believes that this research is of great significance for China and the world in addressing the issue of using carbon dioxide to produce starch – a fundamental food and raw material for humanity – as well as in advancing efforts toward carbon neutrality. However, the realization of the above outlook still depends on certain conditions. For example, first of all, the cost of this conversion process needs to be further reduced to make it economically viable compared to agricultural cultivation; only then can it be possible to conserve arable land and freshwater resources, avoid the negative environmental impacts of pesticides and fertilizers, improve human food security, and promote a bioeconomy that achieves carbon neutrality.

This exploration reveals that there is still a long way to go before industrial application is possible! Imagine: as described, 11 reaction steps are required! ? The yield of starch is unlikely to exceed 20%, the content of various impurities that are difficult to separate accounts for over 80%, and the cost is estimated to be no less than 100 yuan per jin; therefore, it is also unethical to feed such expensive synthetically produced starch to animals.

With this path, it will definitely take a long time to bring it into reality