Adriana Artunduaga, student of the Master in Food Sciences, investigates the generation of polymeric matrices for the reduction of Biofilm in bacteria

This is a research developed within the framework of the thesis project of the Master’s program in Food Sciences of the Austral University of Chile, which today is accredited until 2028.

Millaray Mariqueo, Science in Chile.- The Program responds to the need to create specialists in food science and technology who are capable of developing research based on market needs and food production, preservation, and processing.

Within this framework, Adriana Artunduaga Rojas, a thesis student of the program, developed her research as part of a Fondecyt project initiation 11190667, on the generation of polymeric matrices for the inhibition of the Biofilm of bacteria. listeria monocytogenes and staphylococcus aureus.

Adriana worked with two polymers, polylactic acid and polyvinyl alcohol, “both polymers are eco-friendly because they are degradable, so I added nisin to these polymers -which is a biocide agent- and did different tests, both microbiological, physicochemical and mechanical to evaluate these matrices” he indicated.

The first stage was to form these polymers with nisin, where the student defined the minimum concentration of the agent that the polymers will have, later, she began to test their mechanical properties of elasticity, elongation, and structural properties, and also tested the hydrophobicity and hydrophilicity, to see the degree of permeability of the material. After that, she carried out the microbiological tests with these two microorganisms.

The sponsoring professor of the research was Romina Abarca Oyarce and Co-Sponsoring Professor Kong Shun Ah-Hen.

Results

It was observed that the polyvinyl alcohol incorporated into nisin at a concentration of 5000 international units (IU) allowed better results over time, considering that the research was tested in 24 to 72 hours. “I formed a biofilm, which is the consortium of microorganisms that generate a structure on the surface and these are more difficult to eliminate over time, so I created those structures in my matrices and saw the action of this agent or the release in the agent time and better results were observed in polyvinyl alcohol”.

On the other hand, Adriana mentions that it was also seen that the formation of this biofilm on the surface depended on the type of microorganism, therefore there was a material-microorganism link for the generation of the biofilm. “In this case, staphylococcus aureus was a better biofilm maker than listeria monocytogenes, and this is corroborated by several authors, because listeria needs to interact with other microorganisms to form or be a better biofilm maker.”

In conclusion, it depended on the polymer, the microorganism, the electrostatic energies, the formation of hydrogen bonds between the material, the biocide agent and, in this case, the microorganism itself, to generate an elimination or reduction of this bacterial load in time or permanence.

Adriana is currently working at the Universidad Austral with Professor Aníbal Concha, in a FONDEF I+D project, where they work in connection with the industry. In this case, they collaborate with the Lácteos Río Cruces cheese company, Salmones Aysén and with the Chiloé plant.

“We are in the initial part, in seeing how to apply this technology in some rooms that require it, mapping everything that is the environmental microbiome that they have in the different processing rooms and then start doing a simulation here in the pilot plant and see how this technology can be applied in the future” he concluded.