Paper bug test developed

Spanish researchers have developed a sensor and biomarker system that will help the paper industry detect and eradicate biofouling by bacteria in factory equipment.

A team from the Universidad Complutense in Madrid developed the new microorganism identification technique, which allows for rapid detection of the most problematic bacteria.

A great majority of the paper factories, especially those producing recycled paper, suffer from biofouling in their installations. It is caused by certain bacteria that form colonies. They excrete polysaccharides that form a protective and adhesive matrix, known as biofilm. This allows the bacteria to attach to the surface of pipes, tanks and other equipment, which in turn traps other organic matter and non-adhesive bacteria.

The paper industry typically uses wide spectrum biocides at different points through the process to prevent biofilm build-up. However, concerns over toxicity of the agents and the development of resistance by some microorganisms has forced the industry to seek alternative treatments based on enzymes or biodispersants that have less environmental impact and are more specific in their action.

The cellulose and paper research group from the university’s Department of Chemical Engineering developed and patented a method to detect these bacterial species in the paper industry by means of a probe based on in situ hybridisation and fluorescent markers (FISH).

This method is based on the selective reaction of a molecular marker designed to react by attaching to the specific DNA of a particular microorganism. Once attached, part of the marker molecule called fluorophor activates and produces fluorescence. By taking a microscopic image of the medium in which the reaction takes place and processing it digitally, it is possible to count the number of bacteria of each type that are present per unit volume of the sample.

Knowing the bacterial species present in the installations and the concentration, antimicrobial treatments can be tailored for the detected flora and with a better adjusted dosage. The researchers said application of this technique in the paper industry would generate a reduction in the costs of maintaining the installations and greatly reduce the environmental impact associated with the treatments that use biocides.