Thermal instability hinders the industrialization of superoxide dismutase (SOD), a kind of enzymes that has a protective effect against toxic superoxide radicals (O2.-) in both aerobic and anaerobic organisms.

Researchers headed by Prof DONG Zhi-Yang in Institute of Microbiology, Chinese Academy of Sciences solved this obstacle and developed a SOD product with independent intellectual property rights (granted patent No.: ZL200510005207.9). The modified SOD is highly stable and heat-resistant, which retains activity in 100℃ and shows striking stability across a pH spanning from 4.0 to 11.0. The specific activity of SOD is up to 2,000 U/mg. This SOD overcomes the major limitation to its production and can be applied to medicine, health care, food and beverage industry.

They have started collaborating withBEIJING QIHUAMEI BIOTECHNOLOGY CO., LTD. for its industrialization since 2010. Up to now, the pilot production of SOD has been completed and a new set of thermostable SOD production technology has been established. The expression level of thermostable SOD is up to 10,000U/mL. The production line of pure SOD with 1000kg/year capacity was built up in August, 2011 and the annual output will reach 200 million yuan.

Prof. DONG’s group conducted basic research in SOD enzyme from 2006 to 2009. They identified a new gene encoding a thermostable Fe-superoxide dismutase and worked on finding causes of its thermal stability. These studies were published in Applied Microbiology and Biotechnology 75:367–376(2007), Biochimica et Biophysica Acta-Proteins and Proteomics 1784:445–454(2008) and International Journal of Molecular Sciences 10(12): 5498-5512(2009). The project was supported by National High-tech R&D Program of China during the Tenth an Eleventh Five-year Plan Period.

Contact researcher: Zhi-Yang Dong (dongzy@sun.im.ac.cn)