The aim of this study was to test the potential of high molecular weight exopolysaccharide (EPS) produced by the putative probiotic strain Lactobacillus paraplantarum BGCG11 (EPS CG11) to alleviate inflammatory pain in Wistar rats. The EPS CG11 was isolated from bacterial surface and was subjected to Fourier-transform infrared spectroscopy (FTIR) and thermal analysis. FTIR spectra confirmed the polysaccharide structure of isolated sample, while the thermal methods revealed good thermal properties of the polymer. The antihyperalgesic and antiedematous effects of the EPS CG11 were examined in the rat model of inflammation induced by carrageenan injection in hind paw. The results showed that the intraperitoneal administration of EPS CG11 produced a significant decrease in pain sensations (mechanical hyperalgesia) and a paw swelling in a dose-dependent manner as it was measured using Von Frey anesthesiometer and plethysmometer, respectively. These effects were followed by a decreased expression of IL-1β and iNOS mRNAs in rat’s paw tissue suggesting that the antihyperalgesic and antiedematous effects of the EPS CG11 are related to the suppression of inflammatory response. Additionally, we demonstrated that EPS CG11 exhibits immunosuppressive properties in the peritonitis model induced by carrageenan. Expression levels of pro-inflammatory mediators IL-1β, TNF-α and iNOS were decreased, together with the enhanced secretion of anti-inflammatory IL-10 and IL-6 cytokines, while neutrophil infiltration was not changed. To the best of our knowledge, this is the first study which reports an antihyperalgesic effect as the novel property of bacterial EPSs. Given the high demands of pharmaceutical industry for the replacement of commonly used analgesics due to numerous side effects, this study describes a promising natural compound for the future pharmacological testing in the area.

Although selenium nanoparticles (SeNPs) have gained attention in the scientific community mostly through investigation of their anticancer activity, a great potential of this nanomaterial was recognized recently regarding its antimicrobial activity. The particle form, size, and surface chemistry have been recognized as crucial parameters determining the interaction of nanomaterials with biological entities. Furthermore, considering a narrow boundary between beneficial and toxic effects for selenium per se, it is clear that investigations of biomedical applications of SeNPs are very demanding and must be done with great precautions. The goal of this work is to evaluate the effects of SeNPs surface chemistry and structure on antimicrobial activity against several common bacterial strains, including Staphylococcus aureus (ATCC 6538), Enterococcus faecalis (ATCC 29212), Bacillus subtilis (ATCC 6633), and Kocuria rhizophila (ATCC 9341), as well as Escherichia coli (ATCC 8739), Salmonella Abony (NCTC 6017), Klebsiella pneumoniae (NCIMB 9111) and Pseudomonas aeruginosa (ATCC 9027), and the standard yeast strain Candida albicans (ATCC 10231). Three types of SeNPs were synthesized by chemical reduction approach using different stabilizers and reducing agents: (i) bovine serum albumin (BSA) + ascorbic acid, (ii) chitosan + ascorbic acid, and (iii) with glucose. A thorough physicochemical characterization of the obtained SeNPs was performed to determine the effects of varying synthesis parameters on their morphology, size, structure, and surface chemistry. All SeNPs were amorphous, with spherical morphology and size in the range 70–300 nm. However, the SeNPs obtained under different synthesis conditions, i.e. by using different stabilizers as well as reducing agents, exhibited different antimicrobial activity as well as cytotoxicity which are crucial for their applications. In this paper, the antimicrobial screening of the selected systems is presented, which was determined by the broth microdilution method, and inhibitory influence on the production of monomicrobial and dual-species biofilm was evaluated. The potential mechanism of action of different systems is proposed. Additionally, the cytotoxicity of SeNPs was examined on the MRC-5 cell line, in the same concentration interval as for antimicrobial testing. It was shown that formulation SeNPs-BSA expressed a significantly lower cytotoxic effect than the other two formulations.

In recent years, biopolymer-based nano-drug delivery systems with antioxidative properties have gained significant attention in the field of pharmaceutical research. These systems offer promising strategies for targeted and controlled drug delivery while also providing antioxidant effects that can mitigate oxidative stress-related diseases. Generally, the healthcare landscape is constantly evolving, necessitating the continual development of innovative therapeutic approaches and drug delivery systems (DDSs). DDSs play a pivotal role in enhancing treatment efficacy, minimizing adverse effects, and optimizing patient compliance. Among these, nanotechnology-driven delivery approaches have garnered significant attention due to their unique properties, such as improved solubility, controlled release, and targeted delivery. Nanomaterials, including nanoparticles, nanocapsules, nanotubes, etc., offer versatile platforms for drug delivery and tissue engineering applications. Additionally, biopolymer-based DDSs hold immense promise, leveraging natural or synthetic biopolymers to encapsulate drugs and enable targeted and controlled release. These systems offer numerous advantages, including biocompatibility, biodegradability, and low immunogenicity. The utilization of polysaccharides, polynucleotides, proteins, and polyesters as biopolymer matrices further enhances the versatility and applicability of DDSs. Moreover, substances with antioxidative properties have emerged as key players in combating oxidative stress-related diseases, offering protection against cellular damage and chronic illnesses. The development of biopolymer-based nanoformulations with antioxidative properties represents a burgeoning research area, with a substantial increase in publications in recent years. This review provides a comprehensive overview of the recent developments within this area over the past five years. It discusses various biopolymer materials, fabrication techniques, stabilizers, factors influencing degradation, and drug release. Additionally, it highlights emerging trends, challenges, and prospects in this rapidly evolving field.

In the bone tissue engineering field, there is a growing interest in the application of bioactive glass scaffolds (45S5Bioglass(®)) due to their bone bonding ability, osteoconductivity and osteoinductivity. However, such scaffolds still lack some of the required functionalities to enable the successful formation of new bone, e.g. effective antibacterial properties. A large number of studies suggest that selenium (Se) has significant role in antioxidant protection, enhanced immune surveillance and modulation of cell proliferation. Selenium nanoparticles (SeNp) have also been reported to possess antibacterial as well as antiviral activities. In this investigation, uniform, stable, amorphous SeNp have been synthesized and additionally immobilized within spherical PLGA particles (PLGA/SeNp). These particles were used to coat bioactive glass-based scaffolds synthesized by the foam replica method. Samples were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and transmission electron microscopy (TEM). SeNp, 45S5Bioglass(®)/SeNp and 45S5Bioglass(®)/PLGA/SeNp showed a considerable antibacterial activity against Gram positive bacteria, Staphylococcus aureus and Staphylococcus epidermidis, one of the main causative agents of orthopedic infections. The functionalized Se-coated bioactive glass scaffolds represent a new family of bioactive, antibacterial scaffolds for bone tissue engineering applications.