Biological Sciences

Joanna Sadler wins British Science Association’s Award Lecture Series

Dr Joanna Sadler, BBSRC Discovery Fellow in Biotechnology, is one of seven winners of The British Science Association’s (BSA) prestigious  Award Lecture series for 2022.

Joanna Sadler

The Award Lecturers are a cohort of top early career researchers, based in the UK, who are recognised for their cutting-edge work and commitment to public engagement efforts.

They will present their work at the annual British Science Festival, taking place 13 – 17 September, at De Montfort University (DMU) in Leicester.

Joanna Sadler is the Award Lecture winner for the environmental sciences. Her innovative research uses bacteria to turn plastic waste into vanilla flavouring.

Working in the lab of Dr Stephen Wallace, Joanna lab-engineered the common bacteria E. coli allowing it to transform a plastic bottle into the valuable flavouring chemical, vanillin.

Vanillin is the primary component of extracted vanilla beans and is responsible for the characteristic taste and smell of vanilla, one of the most in demand spices in the world.

Plastic Pollution

The world’s growing plastic crisis has led to the urgent need to develop new ways to recycle polyethylene terephthalate (PET) – the strong, lightweight plastic widely used for packaging foods, juices and water.

Approximately 50 million tonnes of PET waste is produced annually, causing serious economic and environmental impacts. 

This seemingly endless stream of single-use and disposable plastics takes hundreds of years to decompose - with 8m tonnes of plastic waste escaping into oceans every year.

PET recycling is possible, but existing processes create products that continue to contribute to plastic pollution worldwide.

Plastic production also relies on dwindling supplies of non-renewable fossil fuels, such as oil and gas, and the process consumes vast amounts of energy and emits greenhouse gases. 

Engineered Bacteria

Plastic waste
Image Credit - Getty Images

To tackle these problems, Joanna used lab engineered E. coli to transform terephthalic acid – a molecule derived from PET – into vanillin, via a series of enzyme-catalysed chemical reactions.

The team say that the vanillin produced would be fit for human consumption but further experimental tests are required.

Vanillin is widely used in the food and cosmetics industries, as well as the formulation of herbicides, antifoaming agents and cleaning products. 

Global demand for vanillin far exceeds the supply of its natural source – vanilla beans. In 2018 demand soared to 37,000 tonnes - 1.5 times the weight of the Statue of Liberty.

However synthetic production of this popular ingredient suffers many of the same problems as plastic production as it derived from the same source – fossil fuels.

The two-step process, which relies on the petrochemical raw material guaiacol, requires high temperatures and results in spiralling greenhouse gas emissions.

Using bacteria to make the lucrative flavouring is more sustainable as the one pot-process occurs at room temperature and does not generate toxic waste or greenhouse gas emissions.

The approach not only cuts out the use of fossil fuels entirely but could provide a way to up-cycle our way out of the plastic waste crisis.

Related Links

Dr Joanna Sadler

Dr Stephen Wallace

British Science Association – Award Lecture announcement