Laccases are multicopper-oxidases with variety of biotechnological applications. While predominantly used, fungal laccases have limitations such as narrow pH and temperature range and their production via heterologous protein expression is more complex due to posttranslational modifications. In comparison, bacterial enzymes, including laccases, usually possess higher thermal and pH stability, and are more suitable for expression and genetic manipulations in bacterial expression hosts. Therefore, the aim of this study was to identify, recombinantly express, and characterize novel laccases from Pseudomonas spp. A combination of approaches including DNA sequence analysis, N-terminal protein sequencing, and genome sequencing data analysis for laccase amplification, cloning, and overexpression have been used. Four active recombinant laccases were obtained, one each from P. putida KT2440 and P. putida CA-3, and two from P. putida F6. The new laccases exhibited broad temperature and pH range and high thermal stability, as well as the potential to degrade selection of synthetic textile dyes. The best performing laccase was CopA from P. putida F6 which degraded five out of seven tested dyes, including Amido Black 10B, Brom Cresol Purple, Evans Blue, Reactive Black 5, and Remazol Brilliant Blue. This work highlighted species of Pseudomonas genus as still being good sources of biocatalytically relevant enzymes.

Development of new types of antimicrobial coatings is of utmost importance due to increasing problems with pathogen transmission from various infectious surfaces to human beings. In this study, new types of highly potent antimicrobial polyurethane composite films encapsulated by hydrophobic riboflavin-based carbon polymer dots are presented. Detailed structural, optical, antimicrobial, and cytotoxic investigations of these composites were conducted. Low-power blue light triggered the composites to eradicate Escherichia coli in 30 min, whereas the same effect toward Staphylococcus aureus was reached after 60 min. These composites also show low toxicity against MRC-5 cells. In this way, RF-CPD composites can be used for sterilization of highly touched objects in the healthcare industry.

Plastic pollution is now considered one of the largest environmental threats facing humans and animals globally. Development of bioplastic materials may offer part of the solution as bioplastics include both nondegradable and biodegradable materials with both being important for sustainability. Bioplastic materials are currently being designed to encompass minimal carbon footprint, high recycling value and complete biodegradability. This review examines recent developments and trends in the field of bioplastic materials. A range of the most utilized bioplastic materials is presented (poly(lactic acid) (PLA), polyhydroxyalkanoate (PHA), starch, cellulose, bio-based poly(butylene succinate) (bio-PBS) and bio-polyethylene (bio-PE)) including their production, application and degradation options.

The quest for sustainable biomaterials with excellent biocompatibility and tailorable properties has put polyhydroxyalkanoates (PHAs) into the research spotlight. However, high production costs and the lack of bioactivity limit their market penetration. To address this, poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) was combined with a bacterial pigment with strong anticancer activity, prodigiosin (PG), to obtain functionally enhanced PHBV-based biomaterials. The samples were produced in the form of films 115.6–118.8 µm in thickness using the solvent casting method. The effects of PG incorporation on the physical properties (morphology, biopolymer crystallinity and thermal stability) and functionality of the obtained biomaterials were investigated. PG has acted as a nucleating agent, in turn affecting the degree of crystallinity, thermal stability and morphology of the films. All samples with PG had a more organized internal structure and higher melting and degradation temperatures. The calculated degree of crystallinity of the PHBV copolymer was 53%, while the PG1, PG3 and PG3 films had values of 64.0%, 63.9% and 69.2%, respectively. Cytotoxicity studies have shown the excellent anticancer activity of films against HCT116 (colon cancer) cells, thus advancing PHBV biomedical application potential.