QIBEBT-led consortium achieves bacterial degradation of PET bottles to provide terephtalic acid in 97% yield

A research team from the Qingdao Institute of Bioenergy and Bioprocess Technology of the Chinese Academy of Sciences, in collaboration with Nanjing Tech University and Greifswald University, has introduced an innovative solution for the depolymerization of polyethylene terephthalate (PET). This solution utilizes an engineered whole-cell biocatalyst based on the thermophilic bacterium Clostridium thermocellum.

This study builds on prior work, where the research team first demonstrated the concept of whole-cell catalytic PET depolymerization. In that study, the genetically engineered C. thermocellum expressed leaf compost cutinase (LCC) via a plasmid for high-temperature PET depolymerization.

In this study, the researchers integrated LCC directly into the chromosome of C. thermocellum, ensuring stable enzyme expression. They further enhanced the system by introducing LCC variants and co-expressing hydrophobic modules.

By optimizing reaction conditions and controlling pH, the researchers achieved a significant improvement in PET depolymerization efficiency with minimal accumulation of the intermediate product mono(2-hydroxyethyl) terephthalate (MHET).

When tested with pretreated PET bottle particles, about 97% of the added PET was converted into terephthalic acid (TPA), a key monomer used in producing new plastics or high-value chemicals. This high level of performance positions the system as a promising green solution for PET recycling.

Additionally, C. thermocellum is naturally capable of degrading cellulose, making it a potential candidate for directly processing mixed textile waste that contains cotton fibers and PET.

more insights

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.

Green Carbon Journal: call for submissions

Green Carbon is a Quarterly Scientific Open Access Journal published by KeAi and Elsevier https://www.sciencedirect.com/journal/green-carbon

The editorial office is located at the CAS Qingdao Institute of Bioenergy and Environmental Technology, Qingdao, China. The international advisory board has 55 members, including 23 from Europe.

Since September 2093, it has published 108 articles through 9 issues.

Special issue topics included

Green biomanufacturing
Green chemical catalysis
Green photoelectric catalysis
C1 conversion
Green carbon biomanufacturing

Green Carbon is indexed by CAS, SCOPUS (immediate citescore: 14,9), DOAJ, and under full editorial evaluation for inclusion in the ESCI index.

Until now and probably throughout 2026, Green Carbon operates an APC policy free-of-charge

Beyond a journal, Green Carbon, through its host institute CAS QIBEBT, has developed into an international academic exchange platform, which has hosted recent conferences on Green Carbon, Phototrophic Prokaryotes, Clostridia and more, see http://english.qibebt.cas.cn

For further information, consult with the Green Carbon website https://www.sciencedirect.com/journal/green-carbon or with the Green Carbon Offices in Germany through https://window-to-china.de/green_carbon/

A new Fischer-Tropsch route which eliminates CO2 formation

https://en.people.cn/n3/2025/1031/c90000-20384954.html

https://www.science.org/doi/10.1126/science.aea0774

A group at Peking University has developed technology that almost completely eliminates carbon dioxide by-products during Fischer-Tropsch synthesis (FTS), offering a new route to green syngas conversion and low-carbon chemical manufacturing. FTS converts the syngas of carbon dioxide and hydrogen into liquid fuels or high-value chemicals such as olefins. It serves as the pivotal bridge for turning coal, natural gas, biomass and other carbon resources into fuels and value-added chemicals.

The researchers have used a sodium-modified FeC_x@Fe₃O₄ core-shell catalyst coupling water-gas shift (WGS) with syngas-to-olefins (STO) to convert water into hydrogen in situ. HAE reaches about 66 to 83%, exceeding that of methanol-to-olefins (MTO, 50% upper limit). The approximately 95% carbon monoxide conversion and >75% olefin selectivity were simultaneously obtained. The coupling effect was validated by isotope tracing with deuterium oxide and blocking the WGS pathway, and the contribution of WGS was quantitatively evaluated. These results, using lower hydrogen to carbon monoxide ratios, implied that reducing steam consumption in the WGS reaction and reducing the overall output of carbon dioxide and wastewater enabled a sustainable STO process for potential industrialization.

Back to …

青岛 Qingdao
a hub for S&T