Washing away biofilms using fungal cleaning products

Growing inside pipes and on the surfaces of devices, bacterial biofilms cause major headaches for the pharmaceutical sector. Within biofilms, bacteria are protected from chemicals and antibiotics and can be almost impossible to eliminate. But researchers have shown that enzymes produced by yeasts, called biosurfactants, can dissolve stubborn biofilms and boost the efficacy of current chemical treatments, lessening their toxicity and environmental impacts.

Bleach, harsh oxidizing cleaning products, and petrochemical-derived detergents called surfactants combined with scrubbing are the most effective methods of removing biofilms. However, bleach and harsh chemicals are obviously unsuitable for use in biological settings, and while surfactants are used in products such as hand soap and cosmetics, many are toxic to the environment and can damage the surfaces that they are used on.

But in a new study, microbiologists have found a new way of tackling biofilms, using cleaning agents derived from microbes themselves.

Certain Candida yeasts can naturally produce biosurfactants called sophorolipids during the fermentation of oils. Previous studies have shown that sophorolipids have some degree of antimicrobial activity, but there is conflicting information on the effects of these compounds on biofilms composed of the Gram-negative pathogen Pseudomonas aeruginosa.

Specifically, sophorolipids appear to weaken the interaction between the biofilm and the underlying surface and break the internal cohesiveness of the biofilm itself, leading to disruption.

See:

Bac V. G. Nguyen, Toshiki Nagakubo, Masanori Toyofuku, Nobuhiko Nomura, Andrew S. Utada. Synergy between Sophorolipid Biosurfactant and SDS Increases the Efficiency of P. aeruginosa Biofilm Disruption. Langmuir, 2020; 36 (23): 6411 DOI: 10.1021/acs.langmuir.0c00643

Posted by Dr. Tim Sandle, Pharmaceutical Microbiology Resources (http://www.pharmamicroresources.com/)