What is a biofilm?

A biofilm is a community of living microorganisms embedded in a slimy matrix that provides protection against external aggressors, like desiccation, antibiotics, or disinfectants, as well as the host's immune system. This complex matrix consists primarily of polysaccharides, secreted proteins, and extracellular DNA. The capacity to form biofilms is a versatile characteristic of microorganisms. Biofilms are crucial for maintaining infections and biofouling in various industrial settings.

How does a biofilm form?

In reaction to stressful circumstances such as low nutrition, extreme pH and temperature, high salt concentrations, pressure, UV radiation, desiccation, and antimicrobial chemicals, microorganisms form biofilms. They change from free-swimming planktonic to sessile form.

Biofilm formation is a multi-step process involving five critical steps, including the reversible attachment phase, the irreversible attachment phase, the growth phase, the biofilm maturation phase, and the detachment phase. Factors that cause and control the process of biofilm formation include quorum sensing, adverse environmental circumstances, nutritional availability, hydrodynamic conditions, cell-to-cell communication, signaling cascades, and secondary messengers.

Figure below: five phases of biofilm formation

Biofilm formation begins when free-floating bacteria come in contact with and attach to a surface. Many types of bacteria attach to other cells and surfaces through hair-like structures on their surface called pili and fimbriae. This initial attachment is often fragile and is facilitated by adhesins, which are proteins that help bacteria stick more securely to a surface. Once attached, bacteria start to multiply, forming a microcolony. At the same time, they secrete a slimy matrix consisting of extracellular polymeric substances (EPS), which are complex sugars and proteins that shield bacteria from the environment.

As the biofilm grows, the outer layer becomes scarcen nutrients. and parts of it break off, allowing bacteria to spread to another area where they can begin the formation of a new biofilm.

How to detect biofilms?

Food manufacturers often face challenges in detecting biofilms that could contaminate their products. Most of them rely on ATP tests, which are limited to small swabbed areas.

A quicker and more comprehensive way to detect biofilms is to use the XEPU-1720 Bacteria and Biofilm Detector. This portable biofilm detector utilizes unique UV-fluorescing technology to identify biofilms, bacteria, and other surface contaminants. By illuminating the surfaces using the XEPU-1720 Bacteria and Biofilm Detector, quality personnel can identify a wide range of contaminants immediately. The whole process is easy, real-time, and non-destructive.

Photo below: Detect contaminants in sinks at food factories using the XEPU-1720 Bacteria and Bioflm Detector

What are the hazards of biofilm?

Biofilms pose significant potential hazards in various industries such as medicine, industry, and food.

Biofilm on the surface of food processing equipment may contain pathogenic and spoilage bacteria, such as Listeria monocytogenes and Escherichia coli, which can contaminate food and cause food safety issues, posing a threat to consumer health. In additiona, microorganisms in biofilms can decompose nutrients in food, produce odors and harmful substances, and reduce the quality and taste of food.

Therefore, it is crucial for food, milk, and drug manufacturers to detect biofilms in the early stages of biofilm formation.

If you face the challenges of biofilms and are looking for an efficient method to detect biofilms, feel free to contact us for solutions!