From Plastic to Flavor : Transforming Post-Consumer Plastic to Vanillin

The journal Green Chemistry recently published an article on research proposing a way of using bacteria to transform post-consumer plastic into vanillin, the compound which gives vanilla its taste and smell.

"This is the first example of using a biological system to upcycle plastic waste into a valuable industrial chemical and this has very exciting implications for the circular economy,” said Joanna Sadler, first author of the paper, in a statement. "The results from our research have major implications for the field of plastic sustainability and demonstrate the power of synthetic biology to address real-world challenges."

In the new research, conducted by a team at the University of Edinburgh, E. coli was genetically engineered to allow it to convert terephthalic acid – a molecule derived from polyethylene terephthalate (PET) – into vanillin. The team was able to achieve a 79 percent conversion of terephthalic acid to vanillin. They demonstrated the process by converting an old plastic bottle into vanillin, by adding E. coli to the degraded plastic waste.

Next the scientists will further tweak the bacteria to increase the conversion rate further and also work on scaling up the process to convert larger amounts of plastic. Other valuable molecules could also be brewed from terephthalic acid, such as some used in perfumes.

While the researchers claim the vanillin yielded is fit for human consumption, this is yet to be verified and further tests are required. It is also used in the cosmetics industry and is an important bulk chemical, used in herbicides and cleaning products.