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.

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Launch of a mobile deep-sea aquaculture vessel in Qingdao

http://en.people.cn/n3/2025/0418/c90000-20304151.html

A 150,000-tonne deep-sea intelligent aquaculture vessel was delivered for use in Qingdao. The ship is 244.9 meters long and houses 15 breeding cabins with a total water holding capacity of nearly 100,000 cubic meters.

The ship-borne smart aquaculture system is expected to have an annual output of 3,600 tonnes of high-quality fish. The breeding cabins can be used to cultivate fish species such as large yellow croaker and salmon.

The new aquaculture vessel is an updated version of its 100,000-tonne predecessor delivered in 2022. Its predecessor has now already traveled over 17,000 nautical miles. The vessel pushed the aquaculture area from nearshore to deep sea, using high-quality seawater resources for breeding.

An exosceleton for mounting climbing tested at Taishan mountain, Qingdao

http://j.people.com.cn/n3/2025/0207/c517455-20273369.html

https://www.recordchina.co.jp/b948125-s6-c20-d0189.html

During the Chinese New Year holiday, a mountain climbing support robot jointly developed by Taishan Wenlun Group and Shenzhen Kenqi Technology Co. was test-introduced in the Taishan Scenic Area. Guangming reported.

According to Taishan Wenlun Group, the mountain climbing support robot can be used in a wide range of areas in daily life and work, such as mountain climbing, fitness, running, walking, and climbing up and down stairs. It weighs just 1.8 kilograms and is ergonomically designed with power, electronics and artificial intelligence (AI) algorithms. It can sense every movement of the lower limbs and provide support at the right time.

According to the group, it can operate continuously for more than five hours. The product is currently in the trial operation phase, and the company plans to launch 200 units on the market in early March.

A deep-sea salmon farming facility near Qingdao

https://jp.news.cn/20250116/9dc88fa0753f468da2fc4772c53548ec/c.html?page=1

In a large-scale deep sea smart fishery farming facility “Deep Blue 2” in the Qingdao National Deep Sea and Ocean Green Aquaculture Test Area, approximately 400,000 salmon are farmed in farming cages, with a high survival rate and healthy growth.

According to Gu Qihuan, production manager at Shandong Caijing Wanzefeng Marine Technology Co., Ltd., salmon farming requires strict environmental conditions, and it is very difficult to find suitable sea areas for large-scale farming. However, this location is home to 130,000 square kilometers of Yellow Sea cold water mass, and the water temperature in summer is 10 to 16 degrees Celsius, which is very suitable for salmon growth. Deep Blue 2 sinks to the level of the cold water mass less than 30 meters in summer and rises to the surface again in winter.

Deep Blue 2 is 71.5 meters high, 70 meters in diameter, and has a fully submerged farming area of 90,000 cubic meters. It is equipped with multiple smart farming equipment such as an automatic feeding system and an underwater photography system, making unmanned farming in the deep sea and distant ocean possible.

For harvest, schools of salmon are sucked up one after another onto work boats, passed through a fish-water separator, and transported to a workshop for processing. Workers place the salmon in insulated boxes filled with ice and transport them to land overnight for processing and sale.

The freshly caught salmon weigh an average of 3-4 kilograms each, and each harvest is about 5,000 fish. At the earliest, they can be delivered to major cities in China in just over 30 hours.

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