Scientists use micro-organisms to produce 'green' plastic

Korean researchers have developed a unique biorefinery system to create non-natural polymers from natural sources, allowing various plastics to be made in an environmentally-friendly and sustainable manner.

The team from Korea Advanced Institute of Science and Technology (KAIST) developed metabolically engineered Escherichia coli strains to synthesise non-natural, biomedically important polymers including PLGA - previously considered impossible to obtain from bio-based materials.

Renewable non-food biomass can potentially replace petrochemical raw materials to produce energy sources, useful chemicals or products such as plastics, lubricants, paints, fertilisers and vitamin capsules.

In recent years, biorefineries which transform non-edible biomass into fuel, heat, power, chemicals and materials have received a great deal of attention as a sustainable alternative to decreasing the reliance on fossil fuels.

"We presented important findings that non-natural polymers such as PLGA which is commonly used for drug delivery or biomedical devices, were produced by a metabolically engineered gut bacterium," said distinguished professor and lead researcher Sang Yup Lee.

"Our research is meaningful in that it proposes a platform strategy in metabolic engineering, which can be further utilised in the development of numerous non-natural, useful polymers," he added in a paper which appeared in the journal Nature Biotechnology.

"As climate change technology becomes more important, this research on the biological production of non-natural, high value polymers has a great impact on science and industry," noted director Ilsub Baek at the Platform Technology Division of the Ministry of Science, ICT and Future Planning of Korea.