It is the chocking black grease that suffocates fish and weighs down birds, but now a bacteria found in petroleum sludge has been found that could "eat" water pollutants.
Recent work by researchers at UAE University in Al Ain could help take the long-used method of bioremediation — the use of microorganisms to break down pollutants — a step forward.
Dr Salman Ashraf and Dr Ranjit Vijayan have identified a strain of bacillus cereus bacteria from petroleum sludge that can, in just hours, break down pollutants in water. They have named it UAEU-H3K6M1, after the university.
While it is normal for bacteria to be able to break down naturally occurring hydrocarbons, such as those typically found in oil, there may be more stubborn pollutants, including some types of human-made pesticides, that are not so easily broken down.
UAE University's new strain of bacteria could prove useful for dealing with these artificial pollutants, where other bacteria may struggle.
Regulations on the release into the environment of GMOs make it difficult to genetically engineer bacteria to have particular properties in terms of what substances they break down. That means it is important to identify naturally occurring bacteria with new properties.
As reported in their paper in the journal Microbiology Resource Announcements, the scientists, among them an Emirati master's degree student, Manal Al Hefeiti, purified a dozen bacteria from petroleum sludge and screened these according to their ability to degrade synthetic dyes and various types of contaminants.
They settled on one strain that seemed the most promising — it was able to achieve results in as little as four hours — and analysed it to produce a draft sequence of its genome.
“We always suspected that any sludge would be full of potentially interesting bacterial strains. However, with petroleum sludge, we hypothesised that this would be especially rich in bacteria with the ability to degrade and 'eat' organic pollutants,” he said.
“We have been able to use this strain to degrade a variety of 'emerging pollutants', such as pesticides, antibodies and personal-care products that are increasingly being detected in various water bodies.
“We are now exploring ways to immobilise this bacteria in solid support so that we can use it in bioreactors to treat large amounts of waste water.
“One can theoretically use it for cleaning up contaminated land as well. Since this bacteria is from UAE petroleum sludge and is already present in the environment — it is not bioengineered — then one can theoretically spray these bacteria over contaminated lands and allow them to 'eat up' and degrade the pollutants.”