Trans-aconitic acid from Aspergillus terreus – a new biopesticide and bio-based plasticizer

Trans-aconitic acid TAA (CAS RN 4023-65-8) is an unsaturated tricarboxylic acid that occurs in various plants. Although it exhibits broad application potential in agriculture, food, biomaterials, and green chemistry, its practical use remains limited. This is primarily because the traditional production processes of plant extraction (from sugar cane)and chemical synthesis (complex and inefficient) cannot achieve large-scale production at a low cost.

Researchers around LU Xuefeng, director of the Qingdao Institute of Bioenergy and Bioprocess Technology (QIBEBT) under the Chinese Academy of Sciences, have now established a cell factory for the production of TAA based on a genome-edited industrial strain of Aspergillus terreus. Several rounds of metabolic engineering resulted in strains which produced 57 g/L TAA in shake flask cultures. Scale-up to tank fermentations up to 120 kL – in cooperation with Shandong Lukang Pharmaceutical Co., Ltd.– then led to yields of 88 g/L after 100 hours. A simple recovery procedure combining membrane concentration and crystallization provided TAA crystals with a purity of 98.4%. Given its superior nematicidal properties, QIBEBT and Lukang Pharmaceutical are now in the process of registering TAA as a new nematicide biopesticide.

The QIBEBT team has further found that TAA esters (trans-Aconitates) can be used as plasticizers and could replace the ambiguous phthalates widely used in plastic products. Haier Blood Technology Co., a Qingdao-based company, plans to use TAA esters as plasticizers in its PVC-based blood bags and other products.

TAA ester’s wide temperature stability, from -46°C to 120°C, might also find applications in automotive cable materials as they exhibit excellent resistance to high-temperature volatilization and low-temperature brittle cracking.

In summary, biomanufacturing based on smart cells of A. terreus has provided a new material, TAA and TAA esters, which offer exciting application potentials as a biopesticide and a non-toxic bioplasticizer.

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UNESCO endorses Green Carbon Programme to achieve sustainable development goals (SDGs)

http://english.qibebt.cas.cn/ne/rp/202512/t20251201_1134324.html

UNESCO’s “Decade of Sciences” aims to engage science in achieving its sustainable development goals (SDGs).

UNESCO has just endorsed the long-standing commitment of the Qingdao Institute of Bioenergy and Bioprocess Technology QIBEBT to providing open science solutions for green and sustainable technologies.

QIBEBT’s “Green Carbon Programme” focuses on four core themes,

development and utilization of green carbon resources,
green conversion and utilization of fossil carbon resources,
efficient fixation and utilization of carbon emissions, and
analysis and management of multi-scale carbon cycles.

In addition, QIBEBT operates the editorial office of the Green Carbon journal https://www.sciencedirect.com/journal/green-carbon which offers an in-depth and multidisciplinary view of research advances in the field.

With the leverage of the UNESCO endorsement, QIBEBT will boost its efforts to drive innovation and improve public science literacy, supporting high-quality, sustainable, and low-carbon development in China and worldwide for achieving the SDGs.

A novel artificial carbon fixation pathway LATCH with 10 enzymatic steps

https://www.sciencedirect.com/science/article/pii/S2950155525000667?via%3Dihub

https://www.cas.cn/syky/202511/t20251125_5089765.shtml

A research team at the CAS Tianjin Institute of Industrial Biotechnology has proposed a novel artificial carbon fixation pathway—LATCH which comprises 10 completely known enzymatic steps. Each cycle converts two molecules of HCO₃⁻ into one molecule of acetyl-CoA, requiring only adenosine triphosphate (ATP) and reduced coenzyme II for energy. Kinetic and thermodynamic modeling analysis shows that it is a linear autocatalytic cycle structure without kinetic traps or thermodynamic barriers, possessing high feasibility and potential for continued development. It can provide insights for improving the efficiency of systems such as photosynthetic microorganisms, plants, and engineered cell factories.

Regarding the selection of parental modules, the research team referenced research on the serine cycle and designed a modified version of the serine cycle, simplifying the pathway structure and bypassing the inefficient steps involving hydroxypyruvate, thus enabling the pathway to function effectively in the heterologous host *E. coli*. Simultaneously, the team replaced the amino acid deamination and transamination steps in the serine cycle with a decarboxylation process, forming an MCG cycle free from formic acid dependence. This cycle can further convert glycerate 3-phosphate produced by processes such as the Calvin cycle and glycolysis into acetyl-CoA in a negative carbon mode. The study also referenced a series of photorespiration bypass concepts developed for recovering the Rubisco byproduct glycolate-2-phosphate, among which the TaCo module, due to its artificial carboxylation reaction, theoretically has a maximum yield of 150%. This study found that by introducing glyoxylate reductase as a key step to act as a “molecular latch,” the natural serine cycle and the artificially carboxylated module TaCo can be recombined, resulting in a functional transformation—from two parent modules dependent on organic substrates to a complete carbon-fixing cycle.

Based on the LATCH cycle formed by module integration, kinetic analysis shows that this pathway is a linear autocatalytic cycle, theoretically avoiding kinetic traps while eliminating the need to establish complex regulatory relationships. Meanwhile, eight steps in the pathway receive thermodynamic support from adenosine triphosphate (ATP), reducing power, or high-energy substrates, and the remaining two lyase-catalyzed processes do not pose thermodynamic bottlenecks. These inherent advantages at the stoichiometric, kinetic, and thermodynamic levels lay the foundation for the continued development and application of LATCH.

Nature 2025 science city ranking: six of top 10 in China, Qingdao is 31 between Munich and Berlin

https://www.nature.com/nature-index/supplements/nature-index-2025-science-cities/tables/overall

https://en.people.cn/n3/2025/1118/c90000-20391615.html

The newly released “Nature Index 2025 Science Cities” supplement shows that the number of Chinese cities in the global top ten rose from five in 2023 to six in 2024, marking the first time China holds a majority in the rankings.

The supplement draws on the Nature Index database, which tracks research articles published from 2015 to 2024. Its analysis uses “Share”, a fractional count reflecting institutional contribution to publications, as the primary metric, with time-series data adjusted to 2024 levels. Each city’s Share is calculated by summing the contributions of all affiliated institutions located within that city.

According to the Nature Index, the world’s leading science cities overall are: Beijing, Shanghai, New York metropolitan area (U.S.), Boston metropolitan area (U.S.), Nanjing (China), Guangzhou (China), San Francisco Bay Area (U.S.), Wuhan (China), Baltimore-Washington metropolitan area (U.S.), and Hangzhou (China).

Further analysis shows that Chinese cities hold a strong advantage in chemistry, physical sciences, and earth and environmental sciences, leading the global rankings in all three fields. Notably, Chinese cities claimed all of the top ten positions in chemistry for the first time. In the other two subject areas, they secured six of the top ten spots, with Beijing ranking first worldwide across all three domains.

European cities in the ranking start at 19 (London), followed by Zurich (28), Cambridge (29), Munich (30) and Berlin (32), following Qingdao at position 31.

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