Selected Biological Properties and Practical Importance of Polylactide Films Containing Dyes

Background and Aims

Film materials were made of biodegradable polylactide and dyes, which were introduced into a polymer matrix. The additional substances used were fuchsin, crystal violet, safranin and malachite green. The aim of this work was to produce colored films and analyze them from a biological perspective.

Methods

We measured the biological oxygen consumption of microorganisms (BOD) using an OxiTop Control measurement system. The structure of the film was checked using SEM. The NGS sequencing of the 16SrRNA gene was performed. Mutagenicity analyses were performed according to the Ames test. Biocidal properties were confirmed according to ISO standards.

Results

The most biodegradable foil turned out to be the foil made of PLA containing fuchsin, where the highest oxygen consumption results expressed in mgO₂/L were recorded. In turn, the most favorable environment for biological degradation was soil. A number of bacterial strains were also isolated, which showed the greatest impact on the biodegradation of the analyzed materials. Biopreparations were prepared from them. It was also confirmed that none of the foils produced showed mutagenic properties, while their biocidal properties were confirmed.

Conclusions

During the biodegradation processes, the colonization of the film by specific strains was observed, thanks to which it was possible to select a vaccine influencing the biodegradability of the given films. The films can be used in the food packaging industry due to their biocidal properties and lack of mutagenicity.

Funding: This research was funded by the “Excellence Initiative – Research University”, BIO-degradable PACKaging materials research group (Nicolaus Copernicus University in Toruń, Poland).