Despite the intensive research in the past decade on the microbial bioaccumulation of heavy metals, the significance of redox state for oxidative stress induction is not completely clarified. In the present study, we examined the effect of redox-active (copper and chromium) and redox-inactive (cadmium) metals on the changes in levels of oxidative stress biomarkers and antioxidant enzyme defence in Trichosporon cutaneum R57 cells. This filamentous yeast strain showed significant tolerance and bioaccumulation capability of heavy metals. Our findings indicated that the treatment by both redox-active and redox-inactive heavy metal induced oxidative stress events. Enhanced concentrations of Cu²⁺, Cr⁶⁺ and Cd²⁺ caused acceleration in the production of reactive oxygen species (ROS), increase in the level of oxidatively damaged proteins and accumulation of reserve carbohydrates (glycogen and trehalose). Cell response against heavy metal exposure also includes elevation in the activities of antioxidant enzymes, superoxide dismutase and catalase, which are key enzymes for directly scavenging of ROS. Despite the mentioned changes in the stress biomarkers, T. cutaneum did not show a significant growth diminution. Probably, activated antioxidant defence contributes to the yeast survival under conditions of heavy metal stress.

The human endometrium, previously considered a sterile environment, is now recognized as a low-biomass but biologically active microbial niche critical to reproductive health. Advances in sequencing technologies, particularly shotgun metagenomics, have provided unprecedented insights into the taxonomic and functional complexity of the endometrial microbiome. While 16S rRNA sequencing has delineated the distinction between Lactobacillus-dominant and non-dominant microbial communities, shotgun metagenomics has revealed additional diversity at the species and strain level, uncovering microbial signatures that remain undetected by amplicon-based approaches. Current evidence supports the association of Lactobacillus dominance with endometrial homeostasis and favorable reproductive outcomes. Dysbiosis, characterized by increased microbial diversity and enrichment of anaerobic taxa such as Gardnerella, Atopobium, Prevotella, and Streptococcus, is linked to chronic endometritis, implantation failure, and adverse IVF results. Beyond compositional differences, the endometrial microbiome interacts with the host through immunological, metabolic, and epigenetic mechanisms. These interactions modulate cytokine signaling, epithelial barrier integrity, and receptivity-associated gene expression, ultimately influencing embryo implantation. However, discrepancies between published studies reflect the lack of standardized protocols for sampling, DNA extraction, and bioinformatic analysis, as well as the inherent challenges of studying low-biomass environments. Factors such as geography, ethnicity, hormonal status, and antibiotic exposure further contribute to interindividual variability. Culturomics approaches complement sequencing by enabling the isolation of viable bacterial strains, offering perspectives for microbiome-based biotherapeutics. Emerging 3D endometrial models provide additional tools to dissect microbiome–host interactions under controlled conditions. Taken together, the growing body of data highlights the potential of endometrial microbiome profiling as a biomarker for reproductive success and as a target for personalized interventions. Future research should focus on integrating multi-omics approaches and functional analyses to establish causal relationships and translate findings into clinical practice. This review gives a new insight into current knowledge on the uterine microbiome and its impact on implantation success, analyzed through the lenses of microbiology, immunology, and oxidative stress.

Extremophiles are of significant scientific interest due to their unique adaptation to harsh environmental conditions and their potential for diverse biotechnological applications. Among these extremophiles, filamentous fungi adapted to high-salt environments represent a new and valuable source of enzymes, biomolecules, and biomaterials. While most studies on halophiles have focused on bacteria, reports on filamentous fungi remain limited. This review compiles information about salt-adapted fungi and details their distribution, adaptation mechanisms, and potential applications in various societal areas. Understanding the adaptive mechanisms of halophilic fungi not only sheds light on the biology of extremophilic fungi but also leads to promising biotechnological applications, including the development of salt-tolerant enzymes and strategies for bioremediation of saline habitats. To fully realize this potential, a comprehensive understanding of their ecology, diversity and physiology is crucial. In addition, understanding their survival mechanisms in saline environments is important for the development of astrobiology. The significant potential of applications of halophilic fungi is highlighted.

Lactobacillus species are widely recognized for their probiotic potential, focusing on their mechanisms of health benefits and protection. Here we conducted an in vitro investigation of the probiotic potential with a role in microbiome homeostasis of four strains: Lactiplantibacillus plantarum L6 and F53, Ligilactobacillus salivarius 1, and Lactobacillus helveticus 611. A broad spectrum of antibacterial and antifungal activity was determined. The strain-specific inhibition of Staphylococcus aureus, Streptococcus mutans, Escherichia coli, Pseudomonas aeruginosa, and saprophytic/toxigenic fungi makes them promising as protective cultures. DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS (2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonic) acid) measurements showed that tested samples had strain-specific capacity for scavenging of radicals. The molecular base for the antioxidant potential of two lyophilized forms of active strains was investigated by electron paramagnetic resonance spectroscopy. The MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, with fractions of the most active postbiotics obtained by SEC-FPLC (fast protein liquid chromatography) analysis, showed a wide variety of effects on the growth of a K562 myeloid leukemia cell line. The IC₅₀ (half-maximal inhibitory concentration) of L. salivarius 1 was determined to be 46.15 mg/mL. The proven in vitro functionality of the selected lactobacilli make them suitable for development of target probiotics with specific beneficial effects expected in vivo. Further investigations on produced postbiotics and safety have to be completed before they can be considered as scientifically proven probiotic strains.

Antarctica, with its harsh environmental conditions, is home to a wide variety of microorganisms, including filamentous fungi. The survival of Antarctic mycoflora has led to increasing interest in their adaptation. Extreme low temperatures, low water availability, frequent freeze–thaw cycles, strong winds, ultraviolet radiation, etc., are all prerequisites for accelerated production of reactive oxygen species (ROS) and the occurrence of oxidative stress (OS). Antarctic fungi have effective mechanisms to cope with the damaging effects of ROS. While the distribution, morphology, physiology, and biotechnological potential of these fungi are well documented, the role of oxidative stress in their adaptation is poorly understood. This has been one of the main research topics of our team for a long time, and a number of papers on our results have been published. This review summarizes the existing literature on the induction of oxidative stress in Antarctic psychrophilic, psychrotolerant, and mesophilic fungi by extreme conditions. The most recent and relevant studies reporting on the relationship between cold stress and OS biomarkers and the damaging effects of ROS on key intracellular biomolecules are presented. The contribution of both enzymatic and non-enzymatic antioxidant defenses to the fungal cell response is discussed.