AIMS:To evaluate whether the cell-free supernatant (CFS) of a poultry-derived Lactiplantibacillus sp. strain PCE3 can inhibit biofilm biomass accumulation and hyphal morphogenesis of Candida albicans ATCC 10231 in vitro. METHODS AND RESULTS:Biofilm biomass was quantified by crystal violet staining after 48 h growth in RPMI 1640 plus 2% glucose with 10%, 20%, or 40% (v/v) CFS. Filamentation was induced in RPMI 1640 plus 10% fetal bovine serum at 37 °C and assessed qualitatively by light microscopy, scanning electron microscopy, and representative 24 h microscopy observations. Planktonic growth was summarized by 24-h colony-forming unit counts. CFS inhibited biofilm biomass in a concentration-dependent manner, with mean inhibition of 29.6 ± 8.3%, 48.1 ± 7.2%, and 79.8 ± 5.8% at 10%, 20%, and 40% (v/v), respectively (all p < 0.05 vs control). Under hypha-inducing conditions, 40% CFS shifted morphology from extensive filamentation in untreated controls to predominantly moderate or suppressed filamentation, and representative microscopy supported persistence of this non-filamentous phenotype over the observation period. Planktonic viable counts decreased by up to ~1.1 log10 at 40% CFS, indicating partial growth inhibition without eradication. CONCLUSIONS:Poultry-derived Lactiplantibacillus sp. strain PCE3 CFS showed in vitro anti-virulence activity against C. albicans, reducing biofilm biomass and restraining filamentation more strongly than planktonic growth. These findings support avian-derived postbiotic preparations as an underexplored source of anti-Candida activity for further characterization and validation.

Device- and mucosa-associated candidiasis is difficult to cure because Candida biofilms shield cells from antifungals, leading to relapse and device failure. Standard treatment decisions are still largely guided by planktonic susceptibility tests, which poorly predict the drug exposure needed to clear mature biofilms. Here we synthesize evidence that natural-compound adjuvants can dismantle key biofilm defenses and outline design rules to rationalize biofilm-aware combination therapy. Across Candida albicans, non-albicans species and Candida auris, the most reproducible adjuvant effects fell into three themes: (1) reprogramming adhesion and morphogenesis, (2) disrupting membrane sterol homeostasis, and (3) weakening the extracellular matrix and efflux-mediated tolerance. When paired with standard antifungals, these actions frequently increase killing of established biofilms and reduce the exposures required for eradication. Local delivery approaches that concentrate actives at mucosal surfaces or device interfaces (nano- or surface-directed formulations) further improve intrabiofilm exposure while limiting systemic toxicity. We conclude that translation will require standardized biofilm assays, species-stratified testing and tighter links between biofilm pharmacology and clinically achievable exposure. The framework presented here is intended to help prioritize natural adjuvants and combinations most likely to benefit device-associated and mucosal candidiasis.

Candida albicans biofilms are difficult to eradicate because early adhesion and hyphal development promote surface colonization and antifungal tolerance. This study evaluated commercially obtained synthetic cinnamyl acetate (CA; ≥98

Ocimum gratissimum L. (African basil) is widely used in ethnomedicine to treat infectious and inflammatory conditions, yet its antifungal mechanisms remain unclear. In this study, we evaluated the essential oil of O. gratissimum L. (OGEO) against Candida albicans biofilms, a clinically relevant driver of antifungal resistance in device-associated infections. Gas chromatography-mass spectrometry identified eugenol as the predominant constituent (59.5%), supported by terpenoid and sesquiterpene derivatives. Functional assays demonstrated potent antibiofilm activity, as exposure to 1% and 2% OGEO reduced viable biofilm cells by >2 log10 CFU/biofilm at Day 1 and sustained ∼70% inhibition at Day 3, with corresponding biomass reductions of ∼65% and ∼80%, respectively. Confocal microscopy revealed marked thinning and fragmentation of hyphal networks, while scanning electron microscopy confirmed collapse of extracellular matrix architecture. Kinetic modeling showed that OGEO induced an intermediate suppression profile, delaying biofilm recovery compared to untreated controls and fluconazole (which permitted ∼90% regrowth by Day 7), but without the sustained fungicidal effect observed with caspofungin (>80% suppression). Transcriptomic profiling at Day 3 identified 463 differentially expressed genes, with strong repression of hyphal regulators (HWP1, ALS3, EFG1, BCR1) and extracellular matrix-associated genes (FKS1, ZAP1), alongside upregulation of oxidative and proteotoxic stress pathways (SOD5, HSP90, MAPK signaling). Together, these data suggest that OGEO functions as a biofilm modulator rather than a fungicidal agent, weakening structural resilience and redirecting C. albicans into a stress-adaptive state. Clinically, this modulatory activity-marked by early biomass suppression, matrix destabilization, and transcriptional remodeling-highlights OGEO's potential as a prophylactic or adjunctive strategy in device-associated candidiasis. Applications may include medical device coatings or topical formulations that prevent biofilm initiation and enhance susceptibility to existing antifungal drugs.

AIMS:To describe Candida species distribution and antifungal susceptibility in a Vietnamese tertiary-hospital collection and to evaluate Ocimum gratissimum L. essential oil (OGEO) as an in-vitro adjunct to clotrimazole. MATERIALS AND METHODS:We retrospectively analysed 423 clinical Candida isolates collected in 2017-2018. Species identification used routine phenotypic methods/VITEK 2; susceptibility to fluconazole, voriconazole, and amphotericin B followed CLSI M27-A3. OGEO was chemically profiled by GC-MS. Crystal violet assays assessed OGEO inhibition of biofilm formation in 30 C. albicans isolates, and checkerboard assays evaluated OGEO-clotrimazole interactions in 20 species-resolved isolates using FICI. RESULTS:Species-level identification was available for 212 isolates; C. tropicalis (25.8% of the full cohort) slightly exceeded C. albicans (21.8%), while 49.8% were recorded as Candida spp. Overall fluconazole resistance was 13.7%, with higher resistance in C. tropicalis than C. albicans. OGEO was eugenol-rich (66.7%) and inhibited C. albicans biofilm biomass by 71.2% at 1% and 89.6% at 2% v/v. OGEO-clotrimazole interactions were FICI-defined synergistic in 65%, additive in 30%, indifferent in 5%, and never antagonistic. CONCLUSION:OGEO showed promising in-vitro anti-biofilm and clotrimazole-potentiating activity, supporting further standardized, species-matched, topical-formulation and safety studies.

AIMS:The purpose of this paper was to develop a dual-active topical gel combining clotrimazole (0.5%) and methyl eugenol (0.15%) and to evaluate its planktonic and antibiofilm efficacy against Candida spp., cytocompatibility, pharmaceutical performance, and benchmarking versus commercial antifungals. METHODS AND RESULTS:Antimicrobial activity was measured by CLSI-adapted agar diffusion and broth microdilution against Candida albicans ATCC 10231, Candida tropicalis PNT31, and azole-tolerant Candida glabrata (ND31, ND32, 961), together with four representative bacteria (Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, Staphylococcus aureus ATCC 29213, and Enterococcus faecalis ATCC 29212). Biofilm inhibition was quantified in a 96-well static model using the minimum biofilm inhibitory concentration (MBIC50​-MBIC100). The gel achieved minimum inhibitory concentrations (MICs) of 125-250 µg·mL-1 and MBIC50 values 2-4 × the MICs. Compared with Canesten® and Daktarin®, MIC and MBIC50 values were consistently lower (≈30-35% lower for azole-tolerant C. glabrata isolates). Cell viability remained > 85% at MIC/MBIC50​, rheology was shear-thinning/thixotropic, and active contents were ≥ 96% retained during stability testing. CONCLUSIONS:In vitro, the clotrimazole-methyl eugenol gel showed low MIC/MBIC50​ values (including against azole-tolerant C. glabrata), maintained cytocompatibility (>85% viability at MIC/MBIC50), and demonstrated robust pharmaceutical attributes, supporting further in vivo validation for biofilm-associated candidiasis.

Oral biofilm-related diseases, such as dental caries and periodontitis, remain among the most prevalent global health issues and are increasingly complicated by antibiotic resistance and biofilm persistence, which limit the effectiveness of conventional treatments. This study addresses the challenges by exploring antimicrobial peptides (AMPs) derived from ameloblastin (AMBN), a protein integral to dental biomineralization and categorized as an intrinsically disordered protein. In humans, the AMBN gene encodes two isoforms, ISO I and ISO II, with distinct but not fully understood functions. Four AMBN ISO I–derived peptides (A, Am, B, Bm) were designed, synthesized, and tested for antimicrobial and antibiofilm activity. Peptides A and Am moderately inhibited biofilms of E. faecalis, S. aureus, and E. coli (MBIC₅₀ within 50–300 µM), including resistant isolates, while B and Bm were more effective against Gram-positive strains, showing the strongest effect against methicillin-resistant S. aureus CNCTC 6271. Cytotoxicity assays showed > 90

IntroductionCandida albicans is a significant human pathogen with the ability to form biofilms, a critical factor in its resistance to antifungal treatments. This study aims to evaluate the antifungal activity and biofilm inhibition potential of Tea Tree Oil (TTO) derived from Melaleuca alternifolia cultivated in Vietnam.MethodsThe antifungal activity of TTO was assessed by determining the Minimum Inhibitory Concentration (MIC), Minimum Fungicidal Concentration (MFC), Minimum Biofilm Inhibitory Concentration (MBIC), and Minimum Biofilm Eradication Concentration (MBEC) using broth dilution methods. The experiments were conducted on C. albicans in both planktonic and biofilm states across concentrations ranging from 0.1 μL/mL to 10 μL/mL.ResultsTTO demonstrated significant antifungal efficacy, with a MIC of 0.1 μL/mL (∼91.217 μg/mL) and an MFC of 10 μL/mL (∼9121.7 μg/mL). It effectively inhibited biofilm formation with a recorded MBIC of 2 μL/mL (∼1824.34 μg/mL). However, MBEC values were not determinable as the concentrations tested did not achieve the eradication of more than 50% of mature biofilm within the experimental conditions.DiscussionThese findings highlight TTO as a promising natural antifungal agent with strong biofilm-inhibitory properties. However, its limited efficacy in eradicating mature biofilms underscores the need for further studies, potentially involving higher concentrations or synergistic combinations with conventional antifungal agents.

Among living organisms, higher animals primarily use a combination of vocal and non-verbal cues for communication. In other species, however, chemical signaling holds a central role. The chemical and biological activity of the molecules produced by the organisms themselves and the existence of receptors/targeting sites that allow recognition of such molecules leads to various forms of responses by the producer and recipient organisms and is a fundamental principle of such communication. Chemical language can be used to coordinate processes within one species or between species. Chemical signals are thus information for other organisms, potentially inducing modification of their behavior. Additionally, this conversation is influenced by the external environment in which organisms are found. This review presents examples of chemical communication among microorganisms, between microorganisms and plants, and between microorganisms and animals. The mechanisms and physiological importance of this communication are described. Chemical interactions can be both cooperative and antagonistic. Microbial chemical signals usually ensure the formation of the most advantageous population phenotype or the disadvantage of a competitive species in the environment. Between microorganisms and plants, we find symbiotic (e.g., in the root system) and parasitic relationships. Similarly, mutually beneficial relationships are established between microorganisms and animals (e.g., gastrointestinal tract), but microorganisms also invade and disrupt the immune and nervous systems of animals.

This research paper presents a novel approach to the green synthesis of silver nanoparticles (AgNPs) using viticultural waste, allowing to obtain NP dispersions with distinct properties and morphologies (monodisperse and polydisperse AgNPs, referred to as mAgNPs and pAgNPs) and to compare their biological activities. Our synthesis method utilized the ethanolic extract of Vitis vinifera pruning residues, resulting in the production of mAgNPs and pAgNPs with average sizes of 12 +/- 5 nm and 19 +/- 14 nm, respectively. Both these AgNPs preparations demonstrated an exceptional stability in terms of size distribution, which was maintained for one year. Antimicrobial testing revealed that both types of AgNPs inhibited either the growth of planktonic cells or the metabolic activity of biofilm sessile cells in Gram-negative bacteria and yeasts. No comparable activity was found towards Gram-positives. Overall, pAgNPs exhibited a higher antimicrobial efficacy compared to their monodisperse counterparts, suggesting that their size and shape may provide a broader spectrum of interactions with target cells. Both AgNP preparations showed no cytotoxicity towards a human keratinocyte cell line. Furthermore, in vivo tests using a silkworm animal model indicated the biocompatibility of the phytosynthesized AgNPs, as they had no adverse effects on insect larvae viability. These findings emphasize the potential of targeted AgNPs synthesized from viticultural waste as environmentally friendly antimicrobial agents with minimal impact on higher organisms.

The escalating antibiotic resistance observed in bacteria poses a significant threat to society, with the global prevalence of resistant strains of Pseudomonas aeruginosa on the rise.

Biofilm formation by unicellular eukaryotes presents major challenges in healthcare, agriculture, and food industries, primarily due to enhanced resistance to environmental stressors and antimicrobial agents. Understanding the regulatory mechanisms of biofilm formation, such as quorum sensing (QS) and cyclic di-GMP signaling, has led to the discovery of novel compounds that can inhibit biofilm development. In 2024, significant advancements were made in identifying compounds like betulinic acid, methyl anthranilate, and pulmonarin B analogues that target these pathways. This review explores the potential applications of these compounds, especially in Vietnam's agriculture and food industries, where biofilm formation contributes to contamination and antimicrobial resistance. The findings underscore the global relevance of biofilm-disrupting technologies and their role in combating biofilm-associated infections and resistance.

Candida albicans, a prominent constituent of the human microbiota, poses a significant health threat due to its opportunistic pathogenicity and adept biofilm-forming capabilities. This research delves into the antifungal attributes and biofilm inhibition potential of Tea Tree Oil (Melaleuca alternifolia) cultivated in Vietnam. Renowned for its bioactive compounds, including terpinen-4-ol, 1,8-cineole, and terpinolene, the essential oil of Melaleuca alternifolia, commonly referred to as tea tree oil (TTO), is scrutinized for its impact on Candida albicans. The study meticulously determines the Minimum Inhibitory Concentration (MIC) and Minimum Fungicidal Concentration (MFC) of TTO against Candida albicans in both planktonic and biofilm states. Additionally, it assesses the biofilm-forming capacity of Candida albicans and establishes the Minimum Biofilm Inhibitory Concentration (MBIC) and Minimum Biofilm Eradication Concentration (MBEC) of TTO. Employing a liquid culture dilution method within a defined concentration range of 0.1 μL/mL to 10 μL/mL, the experimental approach adheres to established protocols. The outcomes reveal a noteworthy MIC and MIC80 of 0.1 μL/mL and 2 μL/mL, respectively, and an MFC of 10 μL/mL for TTO against Candida albicans. Furthermore, TTO exhibits an MBIC of 2 μL/mL, showcasing its efficacy in inhibiting biofilm formation. However, the MBEC of TTO remains uncertain, possibly due to insufficient concentration tested, which may not effectively disrupt over 50% of the pre-formed biofilm mass within 24 hours. These results underscore the promising potential of TTO as a potent antifungal agent and biofilm inhibitor against Candida albicans, offering valuable insights for the innovation of novel therapeutic strategies in the realm of fungal infections.

Metal nanoparticle synthesis via environmentally friendly methods is gaining interest for their potential advantages over conventional physico-chemical approaches. Herein, we propose a robust green synthesis route for lignin-modified silver nanoparticles, utilizing the recovery of lignin as a renewable raw material and exploring its application in valuable areas. Through a systematic approach combining UV-Vis spectroscopy with AAS and DLS, we identified repeatable and scalable reaction conditions in an aqueous solution at pH 11 for homogeneous silver nanoparticles with high uniformity. The TEM median sizes ranged from 12 to 15 nm with circularity between 0.985 and 0.993. The silver nanoparticles yield exceeded 0.010 mol L−1, comparable with traditional physico-chemical methods, with a minimal loss of silver precursor ranging between 0.5 and 3.9%. Characterization by XRD and XPS revealed the presence of Ag-O bonding involving lignin functional groups on the pure face-centered cubic structure of metallic silver. Moreover, the lignin-modified silver nanoparticles generated a localized thermal effect upon near-infrared laser irradiation (808 nm), potentially allowing for targeted applications in the biomedical field. Our study showcases the potential of lignin as a renewable reducing and capping agent for silver nanoparticle synthesis, addressing some shortcomings of green synthesis approaches and contributing to the development of suitable nanomaterials.

Silver nanoparticles (AgNPs) are excellent antimicrobial agents and promising candidates for preventing or treating bacterial infections caused by antibiotic resistant strains. However, their increasing use in commercial products raises concerns about their environmental impact. In addition, traditional physicochemical approaches often involve harmful agents and excessive energy consumption, resulting in AgNPs with short-term colloidal stability and silver ion leaching. To address these issues, we designed stable hybrid lignin-silver nanoparticles (AgLigNPs) intended to effectively hit bacterial envelopes as a main antimicrobial target. The lignin nanoparticles (LigNPs), serving as a reducing and stabilizing agent for AgNPs, have a median size of 256 nm and a circularity of 0.985. These LigNPs were prepared using the dialysis solvent exchange method, producing spherical particles stable under alkaline conditions and featuring reducing groups oriented toward a wrinkled surface, facilitating AgNPs synthesis and attachment. Maximum accumulation of silver on the LigNP surface was observed at a mass reaction ratio mAg:mLig of 0.25, at pH 11. The AgLigNPs completely inhibited suspension growth and reduced biofilm development by 50% in three tested strains of Pseudomonas aeruginosa at a concentration of 80/9.5 (lignin/silver) mg L-1. Compared to unattached AgNPs, AgLigNPs required two to eight times lower silver concentrations to achieve complete inhibition. Additionally, our silver-containing nanosystems were effective against bacteria at safe concentrations in HEK-293 and HaCaT tissue cultures. Stability experiments revealed that the nanosystems tend to aggregate in media used for bacterial cell cultures but remain stable in media used for tissue cultures. In all tested media, the nanoparticles retained their integrity, and the presence of lignin facilitated the prevention of silver ions from leaching. Overall, our data demonstrate the suitability of AgLigNPs for further valorization in the biomedical sector.

Quorum sensing (QS) is a sophisticated bacterial cell-to-cell communication mechanism that allows bacteria to sense population density through the secretion and detection of diffusible small molecular signals. This process leads to the coordinated expression of specific genes at the transcriptional level. Over time, continuous research has elucidated the genetic elements and regulatory principles of QS. Recently, synthetic biology has leveraged these insights to construct genetic circuits incorporating QS components, enabling both intra-species and inter-species artificial communication. These QS-based genetic circuits hold significant potential for applications in biotechnology and biomedicine. This paper reviews several well-characterized microbial QS systems and their functional roles, while also introducing the application of QS-based genetic circuits in cellular communication across species. The paper further discusses the role of QS in the development of biological computing tools, population density regulation, and metabolic flux control, offering a forward-looking perspective on future advancements. For intra-species communication, the focus is on the use of QS systems in constructing biological computing tools, including toggle switches, biosensors, and logic gates in synthetic biology. These tools, designed on the QS mechanism, can more precisely coordinate cellular behavior by integrating biological control circuits to achieve spatial, temporal, and population-level regulation. In the context of inter-species communication, the introduction of QS systems plays a pivotal role in population density control and metabolic flow regulation. By recombining metabolic networks, QS enables the redistribution of metabolic flux in desired pathways, facilitating the regulation of population density and the co-culture of mixed strains. Moreover, combining QS with oscillator models has shown great potential in synchronizing microbial communities. In summary, in-depth research into QS mechanisms and their applications not only lays a solid foundation for understanding microbial ecological competition and dynamic balance, but also offers promising avenues for regulating pathogenic bacteria and developing innovative disease control strategies.

Quorum Sensing (QS) and Machine Learning (ML) hybrid systems represent a groundbreaking innovation in synthetic biology, offering unprecedented control and adaptability in microbial gene regulation and metabolic processes. QS, a microbial communication mechanism, is crucial for coordinating gene expression in response to population density, impacting behaviors such as biofilm formation, virulence, and resource optimization. However, traditional QS systems are constrained by their reliance on static, pre-programmed feedback loops, limiting their flexibility in dynamic, complex environments. This review highlights how integrating advanced ML algorithms—such as reinforcement learning and deep learning—into QS systems can overcome these limitations by enabling real-time data processing, predictive modeling, and dynamic feedback control. Through these innovations, QS-ML systems can autonomously adjust gene expression and metabolic outputs, making them more efficient and scalable in applications ranging from pathogen control to precision medicine and industrial biomanufacturing. Key case studies illustrate the successful deployment of QS-ML systems to combat antimicrobial resistance, optimize bio-production, and enhance therapeutic precision in cancer and immune modulation. Despite the clear advantages, challenges remain in data integration, system robustness, and regulatory oversight. Addressing these hurdles through interdisciplinary collaboration and developing scalable, multi-omics data platforms will be critical for advancing QS-ML systems from experimental settings to real-world applications. This review underscores the transformative potential of QS-ML systems in revolutionizing synthetic biology, with profound implications for personalized medicine, sustainable biomanufacturing, and environmental health.

Marine fouling poses significant challenges to the efficiency and longevity of marine engineering equipment. To address this issue, developing effective marine antifouling coatings is critical to ensure the economic viability, environmental sustainability, and safety of offshore operations. In this study, we developed an innovative green antifouling and wear-resistant coating based on lignin, a renewable and sustainable resource. Lignin is considered environmentally friendly because it is abundant, biodegradable, and reduces reliance on petroleum-based materials. The coating was formulated with a controlled hydrophilic-to-hydrophobic ratio of 2:8, leveraging lignin's unique properties. Applying lignin increased the water contact angle by 14.5 %, improving surface hydrophobicity and contributing to the coating's antifouling efficacy. Moreover, the mechanical strength of the coating was enhanced by approximately 200 %, significantly boosting its durability in harsh marine environments. Additionally, the friction coefficient was reduced by about 85 %, further preventing organism adhesion. These results demonstrate that lignin-based coatings offer a greener alternative to traditional antifouling solutions. The results of this study not only help advance antifouling coating technology but are also consistent with the broader goal of promoting environmental responsibility in marine engineering practice.

Biofilm-associated infections caused by Candida species represent a significant clinical challenge due to their inherent resistance to antifungal therapies. This study evaluates the antifungal efficacy of trans-Cinnamaldehyde, a natural compound derived from Cinnamomum cassia, in comparison to the widely used antifungal agent Nystatin, against both planktonic and biofilm forms of Candida albicans, Candida glabrata, and Candida tropicalis. Biofilms were established in 96-well polystyrene plates and treated with various concentrations of trans-Cinnamaldehyde and Nystatin. The Minimum Biofilm Inhibitory Concentration (MBIC) and planktonic minimum inhibitory concentration (PMIC) were determined using the MTT assay and Scanning Electron Microscopy (SEM) was employed to assess structural changes in biofilms. The results demonstrated that Nystatin exhibited superior antifungal efficacy across all tested species, particularly in biofilm inhibition, with MBIC50 values as low as 0.0015 mg/mL for C. albicans and C. glabrata. In contrast, trans-Cinnamaldehyde showed moderate antifungal activity with MBIC50 values of 0.16 mg/mL for C. albicans and C. glabrata and higher resistance observed in C. tropicalis (MBIC50 of 0.32 mg/mL). SEM analysis revealed significant biofilm disruption in C. albicans following exposure to trans-Cinnamaldehyde, but C. tropicalis exhibited more resilient biofilm structures. Overall, while Nystatin remains the gold standard for antifungal treatment, trans-Cinnamaldehyde presents potential as an adjunctive treatment, particularly for biofilm-related infections in C. albicans and C. glabrata. Further research is required to explore synergistic effects between trans-Cinnamaldehyde and conventional antifungal agents and to optimize its therapeutic application in clinical settings. This study reused measurement results data from our previous publication to include in tables and charts.