Search Results (706)

Antimicrobial resistance and biofilm-associated oral infections require multi-target therapeutic strategies beyond single-extract herbal testing. Using the L-optimal mixture design approach, we optimized a ternary combination of Thymus vulgaris, Moringa oleifera, and Echinacea purpurea ethanolic extracts against Candida albicans and Streptococcus mutans, then characterized the optimized blend’s phytochemistry, antimicrobial and antibiofilm efficacy, time–kill pharmacodynamics, antioxidant capacity, and cytotoxic safety. Through HPLC, apigenin, chlorogenic acid, resorcinol, and ferulic acid were identified as dominant constituents. The optimal blend (Run 14: T. vulgaris 0.331, M. oleifera 0.318, E. purpurea 0.352) achieved a fractional inhibitory concentration index of 0.50 against both organisms, maximum inhibition zones of 3.10 cm (C. albicans) and 4.10 cm (S. mutans), biofilm inhibition of up to 93.2 ± 2.1% for C. albicans and 78.4 ± 2.8% for S. mutans, and confirmed fungicidal and bactericidal activity within 48 and 24 h, respectively. DPPH scavenging ranged from 55.19 to 68.73%, and oral epithelial cells (OEC) viability exceeded 83% at 300 µg/mL. All assays included three independent biological replicates; statistical significance was defined as p < 0.05. These findings identify the T. vulgaris–M. oleifera–E. purpurea blend as a synergistic, multi-target antimicrobial candidate with a favorable preliminary safety profile, supporting further development and evaluation against clinical isolates for oral fungal and bacterial infections. Full article

Post-Byzantine portable icons are complex, multilayered heritage objects whose preservation may be influenced by interactions among their constituent materials, environmental conditions, and associated microorganisms. This study represents the first multidisciplinary investigation of this kind in Greece and examined five painted faces belonging to four post-Byzantine icons using a multidisciplinary approach combining environmental monitoring, stereomicroscopic and cross-sectional examination, Fourier transform infrared (FTIR) and micro-FTIR spectroscopy, scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM–EDS), culture-dependent microbiology, molecular identification, biofilm assessment, amplicon-based metabarcoding, and bacterial functional prediction. The results revealed substantial material and microbial heterogeneity among the examined icons and individual sampling locations. Material characterization revealed differences in the preparation layers, textile reinforcements, pigments, and surface coatings, including calcite, calcium sulfates, kaolinite, Prussian blue, Pb- and Fe-rich pigments, and HgS. Cultivable microorganisms showed variable biofilm-forming capacities. To address the minimal-sampling constraints inherent to cultural heritage objects, amplicon-based metabarcoding was used as a complementary approach to broaden microbial community characterization beyond the fraction recoverable by cultivation. Metabarcoding revealed diverse bacterial and fungal DNA signatures; however, these signatures indicate microbial association and do not, by themselves, demonstrate microbial viability, metabolic activity, or active biodeterioration. No single material- or conservation-related variable consistently explained the observed microbial patterns. Overall, the findings highlight the importance of considering microbial occurrence within the broader context of material composition, environmental conditions, and conservation state. This multidisciplinary approach provides a useful framework for contextualizing potential biological risk and supporting evidence-based preventive conservation strategies for painted wooden heritage objects. Full article

Antimicrobial resistance and the formation of biofilms in Gram-positive pathogens such as Streptococcus pneumoniae and Staphylococcus aureus are making the treatment of infections increasingly difficult. This study systematically evaluates the effect of gliotoxin (GT), an antimicrobial metabolite produced by Aspergillus fumigatus, on bacterial growth and biofilm formation, as well as its activity in combination with antibiotics. Three strains of S. pneumoniae and two strains of S. aureus (one methicillin-susceptible and one methicillin-resistant) were analysed. Planktonic growth was examined, and biofilm prevention assays were conducted by assessing biomass via crystal violet staining and viable cell counts. In addition, the combined effect of GT with cefotaxime and vancomycin was evaluated. GT inhibited planktonic growth and significantly reduced the biomass and viability of biofilms in a concentration-dependent manner. Moreover, its combination with conventional antibiotics (cefotaxime or vancomycin) showed strong synergy, drastically decreasing bacterial survival. These findings highlight the potent antibacterial and anti-biofilm activity of GT and its ability to enhance antibiotic efficacy, providing insight into fungal–bacterial interactions and suggesting potential therapeutic applications. Full article

Synthetic multi-species consortia provide valuable insights into the ecological and structural dynamics of complex microbial biofilms. However, the specialized functional contributions of individual components under severe nutrient limitations remain poorly understood. This study investigated the population dynamics, matrix biogenesis and metabolic potential of a synthetic ‘protolichen biofilm’ model comprising Asterochloris microalgae, Gordonia bacteria, Thelebolus filamentous fungi and Occultifur yeast. The biofilms were cultivated under strict carbohydrate-deficient conditions for 30 days. Population changes, extracellular polymeric substance (EPS) matrix formation, and the concentrations of extracellular DNA (exDNA) and proteins (exProt), as well as potential dehydrogenase activity (via iodonitrotetrazolium reduction), were evaluated across monocultures, binary, ternary and quaternary consortia. Under carbon starvation, the photoautotrophic microalgae dominated the consortium, driving an 11-fold increase in population size in the four-component system and serving as the primary source of exDNA, which increased by up to three orders of magnitude by day 30. The Gordonia sp. exhibited a tenfold expansion by actively localizing to fungal hyphae and microalgal cell walls. This was directly correlated with a sharp increase in metabolic activity. By contrast, Thelebolus sp. initially provided the structural framework via EPS production, but exhibited limited metabolic activity over time. Meanwhile, the Occultifur sp. yeast population was severely suppressed, adopting a sit-and-wait ecological strategy. Spearman correlation analysis revealed that multi-species integration stabilized the community and triggered significant emergent effects in exDNA accumulation and metabolic potential, but only when microalgae were present. These findings demonstrate that microalgae and bacteria primarily drive metabolism and regulation within the protolichen consortia investigated, while fungi and yeast play structural or opportunistic roles. This provides a robust framework for understanding complex symbiotic interactions. Full article

The global emergence of multidrug-resistant fungal pathogens, including Candida auris, Candida albicans, Aspergillus fumigatus, Cryptococcus neoformans, and Pneumocystis jirovecii, poses a growing threat to public health, particularly among immunocompromised individuals. The limited number of available antifungal drug classes and the rapid evolution of resistance mechanisms, including target-site mutations, efflux pump activation, biofilm formation, metabolic adaptation, and stress-response signaling, have substantially reduced treatment efficacy. This review provides a comprehensive overview of current antifungal therapies, their limitations, and emerging molecular targets for next-generation antifungal drug discovery. We highlight promising targets involved in fungal cell wall biosynthesis, membrane integrity, mitochondrial metabolism, virulence regulation, and host–pathogen interactions, emphasizing their interconnected roles within adaptive resistance networks. Attention is given to small-molecule isothiazolone-based inhibitors, including phosphoglucomutase-targeting compounds, as novel candidates capable of disrupting multiple fungal survival pathways. We further discuss advances in combination therapies, anti-virulence approaches, nanotechnology-based delivery systems, and artificial intelligence-driven drug discovery pipelines that integrate multi-omics data, structural modeling, molecular docking, and virtual screening to accelerate therapeutic development. These advances support a transition from conventional single-target strategies toward systems-level, precision-guided antifungal therapies, providing a framework for overcoming multidrug resistance and improving clinical outcomes in invasive fungal infections. Full article

Candida albicans biofilms are a major cause of persistent infections and contribute to antifungal resistance as well as limitations in drug delivery. Targeting virulence traits such as biofilm formation and hyphal transition represents an effective strategy for controlling fungal pathogenicity without exerting strong selective pressure on planktonic growth. In this study, a library of structurally diverse benzophenone derivatives was screened to identify compounds with antibiofilm and anti-hyphal activities against azole-resistant C. albicans. Most benzophenone derivatives exhibited weak antifungal activity (MIC ≥ 200 µg/mL). However, several halogenated benzophenones markedly suppressed biofilm formation. Among them, decafluorobenzophenone at 10 µg/mL displayed the strongest inhibition, reducing biofilm formation to approximately 1–2% of control levels while maintaining substantial planktonic cell viability. Microscopy confirmed hyphal suppression, while qRT-PCR showed a 36-fold reduction in ALS3 expression. These findings indicate that multi-halogenated benzophenones act primarily as anti-virulence agents targeting biofilm formation and hyphal development. Molecular docking suggested a possible interaction of decafluorobenzophenone with the Als3 binding pocket. Decafluorobenzophenone showed low toxicity, with unaffected Caenorhabditis elegans viability at 10 µg/mL, plant germination at 100 µg/mL, and only slight hemolysis at 100 µg/mL. The results highlight halogen substitution as a key structural determinant and identify benzophenone scaffolds as promising leads for developing novel antibiofilm strategies against azole-resistant Candida infections. Full article

The increasing prevalence of dermatophytosis and biofilm-associated infections highlights the need for new therapeutic approaches. This study evaluated the potential of Lavandula stoechas subsp. luisieri essential oil against clinically relevant dermatophytes. The essential oil obtained by hydrodistillation was chemically characterized by gas chromatography–mass spectrometry (GC–MS). Antifungal activity was assessed through determination of minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC), while antibiofilm activity against Epidermophyton floccosum was evaluated by measuring biofilm biomass, extracellular matrix (ECM) deposition, and cell viability. An ex vivo model of Trichophyton rubrum-induced skin infection was used to assess efficacy under tissue-relevant conditions. The essential oil was mainly composed of oxygenated monoterpenes, with trans-α-necrodyl acetate (19.1%), lavandulyl acetate (13.6%), camphor (8.8%), 1,8-cineole (6.1%), and trans-α-necrodol (5.3%) as major constituents. The oil exhibited antifungal activity against all tested dermatophytes (MIC: 12.5–100 μg/mL), induced hyphal morphological alterations, significantly inhibited E. floccosum biofilm formation, particularly ECM deposition, and reduced fungal dissemination in the ex vivo skin model. These findings support the antidermatophytic and antibiofilm potential of L. stoechas subsp. luisieri essential oil, although further studies are required. Full article

Invasive fungal diseases (IFDs) are a global health threat, especially among immunocompromised populations, due to their high mortality rates and the increasing prevalence of antifungal resistance. In recognition of this threat, the World Health Organization (WHO) has designated Cryptococcus neoformans, Candida auris, Aspergillus fumigatus, and Candida albicans as critical-priority fungal pathogens. During host infection, host-derived reactive oxygen species (ROS) function as potent antimicrobial molecules, whereas fungal-derived ROS act as intracellular signaling mediators regulating oxidative stress adaptation, metabolism, virulence, and antifungal tolerance. Although oxidative stress responses have been extensively investigated in individual fungal pathogens, a comprehensive comparative analysis of oxidative stress signaling across these critical fungal pathogens remains limited. This review systematically compares oxidative stress sensing and signaling networks in the four WHO critical-priority fungal pathogens and classifies oxidative stress-associated pathways into conserved, and species-specific regulatory mechanisms. Conserved pathways, including HOG-MAPK, calcineurin, cAMP-PKA, cell wall integrity, and thioredoxin-dependent signaling, are discussed alongside pathogen-specific adaptations that promote biofilm formation, capsule and melanin production, polarized growth, morphogenesis, immune evasion, and antifungal resistance. By integrating conserved and divergent oxidative stress signaling mechanisms, this review provides a comparative framework that advances our understanding of fungal pathogenesis and highlights potential targets for the development of broad-spectrum and species-specific antifungal therapies. Full article

Farnesol is a small isoprenoid metabolite that has emerged as a key regulator of fungal biology beyond its original identification as a quorum-sensing molecule in Candida albicans. This review examines farnesol across pathogenic and non-pathogenic fungi, emphasizing its roles in morphogenesis, biofilm development, stress adaptation, membrane-associated physiology, and ecological interaction. In pathogenic fungi, farnesol modulates virulence-related traits, antifungal susceptibility, and host interaction, while in non-pathogenic systems, it influences growth, differentiation, and metabolic balance. Evidence from Saccharomyces cerevisiae, Trichoderma, Candidozyma auris (formerly known as Candida auris), and other fungi highlights the context-dependent nature of its effects. We also discuss farnesol biosynthesis, secretion, and the apparent absence of canonical salvage pathways in fungi. Together, these findings support a broader view of farnesol as a multifunctional fungal metabolite that links signaling with metabolism. Understanding its diverse biological roles may clarify fungal evolution and inform future strategies targeting fungal persistence, adaptation, and antifungal tolerance. Full article

Endophytic bacteria associated with medicinal plants represent a potential source of microorganisms with useful enzymatic and antagonistic properties. In this study, 14 bacterial isolates were recovered from the leaves, roots, flowers, and petioles of Inula helenium and screened for morphological, biochemical, and hydrolytic characteristics. Isolate IH-B3, which showed the most pronounced starch- and casein-hydrolysis zones during preliminary screening, was selected for further characterization. MALDI-TOF mass spectrometry assigned the isolate to Bacillus subtilis with an identification score of 2.26, and the strain was designated B. subtilis UzMU25. Its 1444 bp 16S rRNA gene sequence was deposited in GenBank under accession number PZ593820. The strain was catalase- and lecithinase-positive but gelatinase- and hemolysis-negative, and it grew at pH 6.5 and in the presence of horse bile under the qualitative assay conditions used. Hydrolysis-zone diameters ranged from 46 to 52 mm for amylase, 34 to 42 mm for protease, and 10 to 16 mm for lipase activity. In direct antagonism assays, UzMU25 inhibited all six bacterial and fungal test organisms, producing inhibition zones of 26–36 mm. Biofilm biomass varied with incubation time and reached its highest corrected OD₅₉₀ value at 12 h (0.780 ± 0.025). Antibiotic-disc testing showed a 10 mm inhibition zone for vancomycin, indicating reduced susceptibility under the applied conditions and requiring further investigation of its genetic basis and potential transferability. No mortality was observed during the preliminary acute oral study following administration of the tested preparation at doses up to 10,000 mg kg⁻¹, and no visible dermal or conjunctival irritation was detected. Overall, UzMU25 exhibited preliminary enzymatic, antagonistic, and biofilm-forming characteristics of biotechnological interest. However, whole-genome antimicrobial-resistance screening and more comprehensive phenotypic and toxicological evaluations are required before the strain can be recommended for probiotic or other practical applications. Full article

Background: Lower limb exoprostheses often lead to stump dermatological pathologies. The mechanisms by which mechanical microtraumas progress to non-healing ulcerative defects due to dysbiosis remain poorly understood. The objective of this study was to analyze mechanical, inflammatory, and infectious stump skin complications and justify the role of bacterial and mycological dysbiosis in blocking tissue regeneration. Methods: A critical narrative review guided by SANRA principles was conducted (PubMed/Scopus, 1980–2026). Data were extracted with a structured query focusing on amputation stumps, prosthetic interfaces, and skin/microbiological complications (dysbiosis, biofilms, and inflammatory markers). Evidence was graded using predefined clinical matrices and integrated through structured evidence collations to synthesize stump–prosthesis pathogenesis. The PRISMA method was not applied due to study heterogeneity. Results: Skin damage dynamics were categorized into three stages: adaptation (up to 12 months), chronic reactive changes (12–24 months), and late proliferative-infectious destruction (>24 months). The sealed liner space creates 100% humidity and alkalization (pH > 6.5). This causes a mycological shift, where resident Malassezia spp. lose dominance to invasive Candida albicans and non-dermatophyte molds (Aspergillus spp., Fusarium spp.). These pathogens form polymicrobial biofilms with Staphylococcus aureus. At the molecular level, delayed regeneration is driven by “frustrated phagocytosis”: macrophages, unable to engulf large fungal hyphae, continuously release reactive oxygen species and enzymes, trapping the wound in the inflammatory phase. Excessive matrix degradation and suppressed angiogenic factors further block epithelialization. Conclusions: The skin under a prosthesis socket forms a unique pathological biotope. Successful regeneration requires preventive mycobiota correction and targeted management of biophysical parameters (pH, humidity) within the “skin–liner” interface. Full article

Fungal infections remain a major threat to human health, with non-albicans Candida (NAC) species causing more than half of all clinical cases and many strains gaining resistance to current treatments rapidly. Previously, N-arachidonoyl ethanolamine (anandamide, AEA) has been studied and shown to possess antibacterial and antifungal properties against various bacteria and Candida albicans. Given the previous findings, we aim here to expand the current preliminary research on AEA to investigate its antifungal activities against clinically relevant NAC species in vitro: Candida glabrata, Candida parapsilosis, and Candidaozyma auris. The minimum inhibitory concentration (MIC) and growth curve analysis determined planktonic inhibition. MTT metabolic assay and ATP production via BacTiter-Glo luminescence assay evaluated biofilm formation. Membrane fluidity, polarization and efflux pump activity were examined using fluorescence probes Laurdan, DiS-C3(3), and Rhodamine 6G, respectively. Reactive oxygen species (ROS) were assessed using DCFH-DA. Biofilm architecture and cell viability were analyzed by spinning disk confocal microscopy (SDCM). AEA reduced MIC values and slowed planktonic growth, while MTT and ATP assays demonstrated a pronounced dose-dependent reduction in biofilm metabolic activity. Membrane-targeted effects revealed increased fluidity and permeability at 125 µg/mL. Notably, AEA rapidly impaired efflux pump activity and induced intracellular ROS production. This effect was accompanied by reduced cell viability, increased proportions of PI-positive cells, and enhanced intracellular dye retention, as confirmed by SDCM. Together, these findings demonstrate that AEA exerts antifungal activity by disrupting membrane integrity and associated cellular functions and provide the first comparative characterization of species-specific membrane and oxidative stress responses to AEA across three major clinically relevant multidrug-resistant NAC species. Full article

Quinoa leaf spot is an important fungal disease that limits quinoa yield and quality. This study aimed to evaluate the pathogenicity of isolates associated with quinoa leaf spot in Qinghai, China, and to screen multifunctional biocontrol bacteria with potential for further development. Pathogenicity assays conducted on healthy quinoa leaves showed that isolates Alternaria alternata AF15 and A. tenuissima AF18 induced typical leaf spot symptoms. The corresponding fungi were successfully re-isolated from the resulting lesions, confirming the pathogenicity of both isolates. Two highly effective biocontrol bacteria, Serratia liquefaciens CB82 and Bacillus velezensis CB316, were subsequently selected through dual-culture assays. Their maximum inhibition rates against the two fungal pathogens reached 56.00% and 57.00%, respectively. Both biocontrol strains exhibited broad adaptability to different temperatures, pH, and NaCl conditions, produced protease, amylase, and cellulase, and showed phosphate-solubilizing activity. Metabolite extraction and fractionation revealed that the antifungal substances were predominantly enriched in the n-butanol fractions, which caused severe shrinkage, surface roughening, breakage, and deformation of the pathogen hyphae. In addition, both strains exhibited strong biofilm-forming capacity and successfully colonized quinoa leaves. Their culturable populations peaked on day 3 after inoculation, reaching 5.58 × 10⁷ and 6.06 × 10⁷ CFU/mL, respectively. In seed germination pouch assays, the bacterial suspensions promoted quinoa root elongation, whereas the fermentation broths increased seedling biomass accumulation in pot experiments. Overall, this study confirmed the pathogenicity of fungal isolates associated with quinoa leaf spot in Qinghai, China, identified two promising biocontrol bacterial strains, and preliminarily characterized their antifungal substances. These findings provide valuable microbial resources and a research basis for the future development of biological control strategies against quinoa leaf spot. Full article

Background: Rising antifungal and antibiotic resistance among Candida species, Staphylococcus aureus, and Enterococcus faecalis has renewed interest in antimicrobial photodynamic therapy (aPDT) as a resistance-independent strategy. Riboflavin 5′-phosphate is a biocompatible, blue-light-activated photosensitizer, but standardized dosing across fungal and bacterial targets is lacking. Objective: The aim of this study was to systematically optimize pre-irradiation incubation time, photosensitizer volume, irradiation time, and laser power for riboflavin 5′-phosphate aPDT (450 nm diode laser) against C. albicans, C. glabrata, C. krusei, S. aureus, and E. faecalis, and compare species susceptibility under optimized conditions. Methods: ATCC strains were treated with 0.1% riboflavin 5′-phosphate across four groups (photodynamic, photosensitizer-only, laser-only, control) in a staged design optimizing incubation (1–30 min), photosensitizer volume (50–150 µL), irradiation time (10–120 s), and power (50–400 mW). Viable counts (CFU/mL) were quantified. Results: Significant reductions occurred only with combined light-plus-photosensitizer treatment. Optimal parameters were 15 min incubation, 100 µL photosensitizer for Candida spp. (50 µL for bacteria), and 120 s at 400 mW, though C. albicans and C. krusei plateaued by 60 s. Maximum reductions were modest: 53.5% (C. albicans), 46.7% (S. aureus), 37.9% (C. glabrata), 35.9% (C. krusei), and 26.5% (E. faecalis), all below 1 log₁₀. A significant light × photosensitizer interaction, confirming photodynamic specificity, was seen for C. albicans, C. glabrata, and S. aureus, but not C. krusei or E. faecalis. Conclusions: Riboflavin 5′-phosphate aPDT under 450 nm light produces reproducible, dose-dependent, species-specific antimicrobial activity, best suited as an adjunctive rather than stand-alone therapy pending biofilm and in vivo validation. Full article

Dysbiosis-related oral biofilm diseases, particularly dental caries and periodontal diseases, pose major global health challenges because ecological shifts within oral microbial communities enhance biofilm virulence, resilience, and host inflammatory responses. Cannabidiol (CBD), a non-psychoactive phytocannabinoid with antimicrobial, antibiofilm, immunomodulatory, and antioxidant properties, has attracted increasing interest as an investigational, ecology-oriented adjunct for oral health applications. This narrative review evaluates current antibiofilm, antivirulence, and host response evidence for CBD in dysbiosis-related oral biofilm diseases, with emphasis on dental caries and periodontal diseases and selected supportive evidence from other oral biofilm-associated conditions. Current evidence suggests that CBD can inhibit biofilm formation, attenuate cariogenic and fungal virulence traits, modulate periodontal inflammation and immunity, and support tissue-protective responses. However, most evidence remains preclinical and model-dependent, particularly in caries research, and CBD’s hydrophobicity, limited stability, uncertain dose windows, and incomplete microbiome-level evidence remain major barriers to translation. Future studies should clarify CBD’s ecological effects on oral microbial communities, define clinically relevant dosing and exposure timing, and develop oral-retentive delivery systems. Full article