Digestate from UK AD plant helping to tackle drug-resistant bacteria

Antibiotics that could help in the battle against drug-resistant bacteria have been discovered in the digestate produced by a UK anaerobic digestion (AD) plant.

The discovery was made after digestate from a facility owned by malt and malted ingredients producer Muntons was sent for analysis to the University College London.

The sample was delivered to Adam Roberts who runs the Swab and Send project, which aims to find new antibiotics by asking the public to swab their everyday environment and send the results to the scientists.

According to Roberts, an anaerobic digester is a competitive environment and as such it is a good place to look for new antibiotics.

“The bacteria are competing with each other for food and other resources, so these kinds of environments have led to the evolution of antibiotics in order to give them the competitive edge,” Roberts told Bioenergy Insight.

Ryland Cairns, environment manager at Muntons, said the unique feedstock within the AD plant may have helped these possible new strains evolve. 

“We were pleased to find out that our AD plant appears to produce antibiotics that could potentially be developed as a medicine in the future to combat Micrococcus and drug resistant E. coli. Due to the varying nature of AD plants and feedstock, it would be great to know what is lurking inside other digesters,” Cairns said.

Identifying the bacteria

Further research is being undertaken as part of the Swab and Send project to identify the strain of bacteria found and subsequently the compound producing it.

Roberts said there has not yet been an opportunity to determine what the found antibiotics are and the chance that they are in fact new and medically significant is “slim”, but the research had produced some encouraging initial results.

“We’ve grown all the bacteria we can from the samples we got and tested those for antibiotics. It would be absolutely wonderful if they can be used because we really need new ones,” he said.

The medical industry has been relying on the same antibiotics for the past 30-40 years, which has caused several strains of dangerous bacteria to become resistant to virtually all existing medicines.

Apart from the anaerobic digester, the Swab and Send project has received samples extracted among other places from fridges, garden trampolines, and cats.

This article was written by Ilari Kauppila, deputy editor at Bioenergy Insight