Candida albicans biofilms: development, regulation, and molecular mechanisms

In silico activity and effect of synthetic chalcones on Candida albicans and Candida tropicalis biofilms

Biofilm formation is considered one of the most important virulence factors for Candida species, which presents an extracellular matrix of polymeric substances that limits the passage of antifungals, leading to fungal resistance. Therefore, the present study investigated the biofilm eradication effect of synthetic chalcones against Candida albicans and Candida tropicalis. Molecular docking studies were conducted to verify the mechanism of action of chalcones on Candida species proteins. The biofilm eradication effect was determined using crystal violet methodology to quantify biomass and Thiazolyl blue tetrazolium bromide (MTT) to verify the influence on metabolic activity. A molecular docking study was also carried out with Candida proteins using the Protein Data Bank repository (https://www.rcsb.org/) and Autodocktools™ software. The results showed that (1E,4E)-1,5-diphenylpenta-1,4-dien-3-one (DB-Acetone), (1E,3E,6E,8E)-1,9-diphenylnona-1,3,6,8-tetraen-5-one (DB-CNM), and (1E,4E)-1,5-bis(4-methoxyphenyl)penta-1,4-dien-3-one (DB-Anisal) were able to eradicate the biomass of C. albicans CA INCQS 40006 (ATCC 10231), while fluconazole only reduced the biomass at the three tested concentrations (IC50, IC50 × 10, and IC50 × 20) against C. tropicalis CT INCQS 40042 (ATCC 13803). Both chalcones and fluconazole successfully reduced metabolic activity across all tested strains. The molecular docking study concluded that DB-Acetone, DB-Anisal, and DB-CNM exhibited significant affinity energy values toward the binding sites of C. albicans and C. tropicalis. It is concluded that the synthetic chalcones showed promising results in inhibiting Candida spp. biofilm, demonstrating efficacy in reducing biomass as well as metabolic activity.

A "three-in-one" thermosensitive gel system that enhances mucus and biofilm penetration for the treatment of vulvovaginal candidiasis

The special physiological barriers of women, such as vaginal mucus and self-cleaning behavior, pose great challenges for the treatment of vulvovaginal candidiasis (VVC), and the drug resistance caused by fungal biofilms limits the application of existing antifungal drugs. Based on this, we designed a "three-in-one" thermosensitive gel system (AF/BP Gel) loaded with antibiofilm nanoparticles (AF NPs) and mucus penetration-assisting nanoparticles (BP NPs) to achieve vaginal adhesion while enhancing mucus and biofilm penetration. AF NPs were loaded with farnesol (FAR) and amphotericin B (AMB), and FAR is one of quorum sensing molecules which can interfere with biofilm-related genes such as ALS3, HWP1, RAS1, CPH1, EFG1, NRG1, TUP1, UME6, and disperse mature biofilm, thus playing a synergic antibiofilm role with AMB. BP NPs was loaded with bromelain (BRO), which cleared the mucus barrier for AF NPs and help it penetrate deep into the infection. These two kinds of nanoparticles use the thermosensitive gel matrix to reach the surface of the vaginal mucosa uniformly and persistently to overcome the obstacle of vaginal self-cleaning. AF/BP Gel showed great anti-candida albicans activity in vitro and in vivo, and greatly improved the inflammatory conditions in VVC mice. Overall, this "three-in-one" thermosensitive gel system can overcome multiple physiological barriers and resist different periods of biofilm, providing a new platform for treating vagina-associated infections.

Invasive candida in the abdomen: how to differentiate infection from colonization

INTRODUCTION

Intra-abdominal candidiasis (IAC) is a serious complication in critically ill patients, particularly after abdominal surgery or trauma. Differentiating Candida colonization from invasive infection is crucial, as misdiagnosis can lead to inappropriate antifungal use, increased resistance, and worse outcomes. However, IAC remains underrecognized due to the limitations of conventional culture-based diagnostics. Relevant literature was identified through a non-systematic search of the PubMed database.

AREAS COVERED

This review highlights the challenges in diagnosing and managing IAC, focusing on the limitations of traditional culture methods and the potential of non-culture-based diagnostics. Biomarkers such as 1-3-β-D-glucan (BDG) and Candida albicans germ tube antibody (CAGTA), along with molecular assays, improve diagnostic accuracy but have varying sensitivity and specificity, requiring a multimodal approach. Management involves early diagnosis, source control, and targeted antifungal therapy. Current guidelines, largely based on candidemia, recommend echinocandins as first-line therapy, with fluconazole for stable patients and amphotericin B for resistant strains.

EXPERT OPINION

Despite advances, IAC-specific research is lacking, necessitating improved diagnostic tools and tailored therapies. There is a need for more targeted studies to refine diagnostic algorithms and therapeutic strategies. Future efforts should focus on developing rapid, high-sensitivity and specific diagnostic tools, optimizing antifungal stewardship, and individualizing treatment approaches.

Targeting biofilm formation in Candida albicans with halogenated pyrrolopyrimidine derivatives

Growing concern over environmental contaminants, including pharmaceuticals and antifungal agents, highlights their role in promoting resistance and biofilm formation by microorganisms. Antifungal resistance, especially in drug-resistant Candida spp., poses a global threat, worsened by the widespread use of antifungal agents in both clinical applications and environmental contamination. This study investigates the antibiofilm properties of various halogenated pyrrolo pyrimidine derivatives, specifically 4-chloro-5-iodo-7H-pyrrolo[2,3-d]pyrimidine (10) and 2,4-dichloro-5-iodo-7H-pyrrolo[2,3-d]pyrimidine (16), against fluconazole-resistant C. albicans. Both compounds demonstrated strong biofilm inhibition, with 16 showing greater efficacy even at lower concentrations. qRT-PCR analysis revealed downregulation of key biofilm- and hyphae/germ tube-relating genes, including ALS3, HWP1, and ECE1, alongside upregulation of stress response and biofilm regulator genes such as CDR11, GST3, IFD6, UCF1, YWP1, and ZAP1, indicating complex regulatory responses to the treatments. Molecular docking analysis revealed that these compounds bind effectively to the binding cavity of the ALS3 protein, with halogen atoms playing a key role in stabilizing interaction. Compound 16 exhibited minimal cytotoxicity in Brassica rapa and Caenorhabditis elegans models, suggesting a favorable ADMET safety profile. Confocal microscopy analysis confirmed the compounds effectiveness in preventing biofilm formation when applied as biodegradable PLGA coatings on biomaterial surfaces. These findings suggest that 16 holds promise as a potent antifungal agent with reduced environmental impact, offering both efficacy and sustainability.

Eicosapentaenoic acid as an antibiofilm agent disrupts mature biofilms of Candida albicans

The biofilm formation of Candida albicans, a major human fungal pathogen, represents a crucial virulence factor during candidiasis. Eicosapentaenoic acid (EPA), a polyunsaturated fatty acid, has emerged as a potential antibiofilm agent against C. albicans. Herein, we aim to investigate the antifungal effect of EPA (1 mM) on the mature biofilm of C. albicans and explore the underlying mechanism. Crystal violet and XTT assays showed that EPA exerted a strong inhibitory efficacy on preformed biofilms in C. albicans. Biofilm architecture and cell viability were observed using scanning electron microscopy and confocal laser scanning microscopy, indicating that EPA could block the yeast-to-hypha transition and damage the structure, thereby exhibiting antibiofilm activity. RNA sequencing analysis revealed that EPA treatment led to the downregulation of genes associated with hyphal formation and biofilm development. From the signaling pathway perspective, EPA regulated the C. albicans biofilms involving two signaling pathways, namely, Ras1-cAMP-PKA and Cek-MAPK pathways. Additionally, the EPA could effectively reduce the production of key messenger cAMP in the Ras1-cAMP-PKA pathway. Interestingly, in response to EPA, ergosterol biosynthesis-related genes were down-regulated, indicating EPA as antifungal agent might reduce the risk of developing drug resistance. The findings of this study highlight the potential of EPA as an alternative or adjunctive antibiofilm agent against C. albicans-related infections.

Chemical composition of the traditional Chinese medicine compound (ICAM), its antifungal effects against Candida albicans, and the underlying Mechanisms: Therapeutic potential and safety evaluation for vulvovaginal candidiasis

ETHNOPHARMACOLOGICAL RELEVANCE

Traditional Chinese medicine (TCM) compound preparations play a significant role in the clinical treatment of vulvovaginal candidiasis (VVC).

AIM OF THE STUDY

Candida albicans (CA) is an opportunistic fungal pathogen responsible for various human diseases, including vulvovaginal candidiasis (VVC). Hyphal growth and biofilm formation are critical virulence factors contributing to CA's pathogenicity and drug resistance. ICAM, a topical TCM compound preparation developed by our laboratory, was investigated for its chemical component, antifungal mechanisms against CA and therapeutic efficacy against VVC.

MATERIALS AND METHODS

The main components of ICAM were analyzed using the Gas Chromatography-Mass Spectrometry (GC-MS) method. To elucidate the mechanisms underlying ICAM's antifungal activity, we combined phenotypic assays, transcriptomic and proteomic analyses. The therapeutic potential of ICAM for VVC and its irritancy to vaginal tissue were evaluated using cavity model experiments.

RESULTS

ICAM contained a diverse range of phenolic compounds, such as phenol, 2-methoxyphenol, and 4-ethyl-2-methoxyphenol, among others. The minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of ICAM against CA were 2.50 % and 10.00 % for the standard strain, and 5.00 % and 20.00 % for the clinical strain, respectively. At 1.25 %, ICAM significantly inhibited CA adherence, hyphal growth, and biofilm formation, while also reducing surface hydrophobicity and exopolysaccharide production. Treatment with 10.00 % ICAM completely disrupted CA membrane integrity. Transcriptome analysis revealed that multiple genes associated with biofilm and hyphal formation, including five MAPK signaling pathway genes (Ras1, Cdc24, Ste11, Cek1, Hst7), four hyphae-specific genes (Hgc1, Hwp1, Ece1, Als3), and three additional genes (Tec1, Csh1, Pmt1), were significantly downregulated. Additionally, proteins associated with the MAPK signaling pathway, including the 14-3-3 domain-containing protein, cell wall protein RTB1, Msb2p, Ras family protein, and RhoGAP domain family protein, were significantly downregulated. These findings suggest that the MAPK signaling pathway plays a crucial role in mediating ICAM's inhibition of hyphal growth and biofilm formation in CA. In vivo, 10.00 % ICAM completely eliminated the symptoms of CA infection. The vaginal fungal burden in the 20.00 % and 40.00 % ICAM groups was reduced to zero after 12 days of treatment. Furthermore, 40.00 % ICAM significantly reduced lactate dehydrogenase and inflammatory cytokine levels, demonstrating efficacy comparable to the positive control. ICAM demonstrated excellent mucosal compatibility in the cavity experiment.

CONCLUSIONS

These findings highlight the potential of ICAM as a novel antifungal agent for the treatment of VVC.

Prophylactic application of sodium new houttuyfonate to regulate macrophage activation and antifungal infection in intra-abdominal candidiasis model mice

The abuse of immunosuppressants causes damage to the immune system, while the pathological proliferation and translocation of symbiotic Candida albicans can result in abdominal infection in immunocompromised people. In this study, we established a mouse peritoneal C. albicans infection model and investigated the effects of preventive application of Sodium New Houttuyfonate (SNH) by analyzing the proportion of immune cells, polarization of peritoneal macrophages, changes in fungal tissue load, and histology, and the data showed prophylactic SNH administration yields a double anti-infection effect in phagocytosis and regulation of immunity according to the immune inflammatory states of the body. In vitro, neutral red, colony counting, cytometric bead array, RT-qPCR, western blot, inhibitor treatment, and detection of reactive oxygen species (ROS) and nitric oxide (NO) production on RAW264.7 macrophages showed SNH can stimulate the production of tumor necrosis factor-alpha (TNF-α) and CC motif ligand 2 (CCL2) and the release of ROS and NO through a TLR2/p38/NF-κB pathway. Taken together, our data provide an innovative insight into the prevention use of exogenous SNH for the treatment of C. albicans infection.

Myricetin Exerts Antibiofilm Effects on Candida albicans by Targeting the RAS1/cAMP/EFG1 Pathway and Disruption of the Hyphal Network

Increasing antifungal resistance and side effects of existing drugs demand alternative approaches for treating Candida (C.) infections. This study aimed to comprehensively evaluate the antifungal efficacy of myricetin (MYR), a natural flavonoid, against both fluconazole (FLC)-resistant and susceptible clinical Candida strains, with a particular focus on its inhibitory effects on C. albicans biofilms. Antifungal susceptibility was evaluated on Candida spp. by the broth microdilution method, and the impact of myricetin on C. albicans biofilms was determined using the Cell Counting Kit-8 (CCK-8) assay. To understand the molecular mechanisms underlying the antibiofilm properties of myricetin, expression analysis of genes in the RAS1/cAMP/EFG1 pathway (ALS3, HWP1, ECE1, UME6, HGC1) and cAMP-dependent protein kinase regulation (RAS1, CYR1, EFG1) involved in the transition from yeast to hyphae was performed. Field emission scanning electron microscopy (FESEM) was used to study the ultrastructural changes and morphological dynamics of Candida biofilms after exposure to MYR and FLC. The in vivo toxicity of myricetin was evaluated by survival analysis using the Galleria mellonella model. Myricetin significantly suppressed key genes related to hyphae development (RAS1, CYR1, EFG1, UME6, and HGC1) and adhesion (ALS3 and HWP1) in both clinical and reference Candida strains at a concentration of 640 µg/mL. FESEM analysis revealed that myricetin inhibited hyphae growth and elongation in C. albicans. This study highlights the promising antibiofilm potential of myricetin through a significant inhibition of biofilm formation and hyphal morphogenesis.

Chemical Elements and Thickness of Candida albicans Biofilm Induced by Glucose, Lactose, Protein, and Iron

Health is the most important aspect that needs to be considered, and the oral cavity cannot be separated from other parts. Candida albicans is a normal flora in the oral cavity that is a major cause of oral candidiasis. Research on biofilms can help prevent oral candidiasis infection in the community. Biofilms are involved in the pathogenesis and could be examined using an electron and fluorescence microscope, which can analyze the whole biofilm in actual conditions. This study aims to determine the chemical elements and thickness of Candida albicans biofilms induced by glucose, lactose, soy protein, and iron.This analytic observational study was carried out by observing the chemical elements and thickness of the biofilm by scanning electron microscopy with energy dispersive X-ray (SEM-EDX) and confocal laser scanning microscopy (CLSM). SEM-EDX data analysis used the EDAX APEX software and CLSM used the Olympus FluoView ver 4.2.a.SEM-EDX examination showed the formation of Candida albicans biofilm induced by glucose, lactose, soy protein, and iron with similarity in the percentage of the most constituent chemical elements, namely, oxygen, carbon, nitrogen, and phosphorus, and the least were sulfur. The thickest biofilm was found in the induction of iron, glucose, and lactose, and the thinnest was soy protein.The chemical elements of Candida albicans biofilm induced by four different inducers has the same percentage of the composition of elements, namely, oxygen, carbon, nitrogen, and phosphorus, and the least were sulfur and the thickest biofilm was by the induction of iron, glucose, and lactose, and the thinnest was by soy protein.

Essential Oils for Biofilm Control: Mechanisms, Synergies, and Translational Challenges in the Era of Antimicrobial Resistance

Biofilms, structured microbial consortia embedded in self-produced extracellular matrices, pose significant challenges across the medical, industrial, and environmental sectors due to their resistance to antimicrobial therapies and ability to evade the immune system. Their resilience is driven by multifaceted mechanisms, including matrix-mediated drug sequestration, metabolic dormancy, and quorum sensing (QS)-regulated virulence, which collectively sustain persistent infections and contribute to the amplification of antimicrobial resistance (AMR). This review critically examines the potential of plant-derived essential oils (EOs) as innovative agents for biofilm control. EOs exhibit broad-spectrum antibiofilm activity through multi-target mechanisms, including disrupting initial microbial adhesion, degrading extracellular polymeric substances (EPSs), suppressing QS pathways, and compromising membrane integrity. Their ability to act synergistically with conventional antimicrobials at sub-inhibitory concentrations enhances therapeutic efficacy while reducing the selection pressure for resistance. Despite their potential, EO applications face technical challenges, such as compositional variability due to botanical sources, formulation stability issues, and difficulties in standardization for large-scale production. Clinical translation is further complicated by biofilm stage- and strain-dependent efficacy, insufficient in vivo validation of therapeutic outcomes, and potential cytotoxicity at higher doses. These limitations underscore the need for optimized delivery systems, such as nanoencapsulation, to enhance bioavailability and mitigate adverse effects. Future strategies should include combinatorial approaches with antibiotics or EPS-degrading enzymes, advanced formulation technologies, and standardized protocols to bridge laboratory findings to clinical practice. By addressing these challenges, EOs hold transformative potential to mitigate biofilm-associated AMR, offering sustainable, multi-target alternatives for infection management and biofilm prevention in diverse contexts.

Phenotypic and Molecular Characterization of Candida albicans Isolates from Mexican Women with Vulvovaginitis

Vulvovaginal candidiasis (VVC) is an opportunistic mycosis that affects women of reproductive age. The most frequent etiological agent is Candida albicans. The development of VVC depends on factors related to the host and the fungus. Among the factors related to Candida spp. are virulence factors, but genotype may also be involved. The objective of this study was to evaluate the ABC genotypes and extracellular hydrolytic enzyme production in C. albicans isolates obtained from Mexican women with vulvovaginitis to determine if there is a correlation between these characteristics that allows the fungus to invade and cause damage to the host. Forty-three yeast isolates were obtained from vaginal exudates from women with symptoms of infection. The isolates were identified by germ tube tests and by Cand PCR. The ABC genotype of the isolates identified as C. albicans was determined through the isolates' DNA amplification using the oligonucleotides CA-INT-R and CA-INT-L. The activity of esterase, phospholipase, proteinase, and hemolysin was evaluated in specific culture media. The correlation between extracellular enzyme production and genotype was analyzed using a two-way ANOVA and the Sidak comparison test. A total of 57.5% of the yeast isolates were identified as C. albicans. The genotypes identified were A (82.6%) and B (17.4%). The activity of esterase, phospholipase, proteinase, and hemolysin was very strong. No statistically significant difference was found between enzyme production and genotypes. In conclusion, genotype A predominates among C. albicans vaginal isolates. The production of extracellular hydrolytic enzymes was widely expressed in C. albicans vaginal isolates, but no correlation with genotype was found.

Roles of alcohol dehydrogenase 1 in the biological activities of Candida albicans

Candida albicans stands as the foremost prevalent human commensal pathogen and a significant contributor to nosocomial fungal infections. In the metabolism of C. albicans, alcohol dehydrogenase 1 (Adh1) is one of the important enzymes that converts acetaldehyde produced by pyruvate decarboxylation into ethanol at the end of glycolysis. Leveraging the foundational processes of alcoholic fermentation, Adh1 plays an active role in multiple biological phenomena, including biofilm formation, interactions between different species, the development of drug resistance, and the potential initiation of gastrointestinal cancer. Additionally, Adh1 within C. albicans has demonstrated associations with regulating the cell cycle, stress responses, and various intracellular states. Furthermore, Adh1 is extracellularly localized on the cell wall surface, where it plays roles in processes such as tissue invasion and host immune responses. Drawing from an analysis of ADH1 gene structure, expression patterns, and fundamental functions, this review elucidates the intricate connections between Adh1 and various biological processes within C. albicans, underscoring its potential implications for the prevention, diagnosis, and treatment of candidiasis.

The association of DNase I with antimicrobial photodynamic therapy affects Candida albicans gene expression and promotes immunomodulatory effects in mice with candidiasis

This study evaluated Candida albicans gene expression and local inflammatory response from mice with oral candidiasis that were treated with DNase I plus antimicrobial photodynamic therapy (aPDT). DNase I was applied, followed by aPDT mediated by Photodithazine® and LED light, singly or combined for five consecutive days. A group was only inoculated with fluconazole-susceptible (CaS) or-resistant (CaR) C. albicans strains. Immediately and 7 days after treatments, C. albicans colonies recovered from mice tongues were used for gene expression evaluation. Tongues from mice killed 24 h and 7 days after treatments were used to evaluate the host's inflammatory cytokines using cytometric bead array. A reduction occurred in the gene expression related to adhesion to the host substrate, the biofilm extracellular matrix, and oxidative stress of CaS and CaR recovered from mice treated with DNAse I plus aPDT. Increased production of IL-6, TNF-α, and MCP-1 occurred in mice infected with CaS but not as much for those infected with CaR in the groups treated with DNase I plus aPDT and aPDT. DNase I plus aPDT decreased the expression of the fungal genes evaluated and increased local inflammatory response, which helped to fight the infection.

Nanoparticles in the battle against Candida auris biofilms: current advances and future prospects

Candida auris has emerged as a significant global health threat due to its multidrug resistance and ability to form robust biofilms, particularly on medical devices and hospital surfaces. Biofilms protect C. auris from antifungal treatments and the host immune response, making infections persistent and difficult to control. This review explores the potential of nanoparticles to overcome the limitations of traditional antifungal therapies in combating C. auris biofilms. Nanoparticles, with their unique physicochemical properties, offer promising strategies to penetrate biofilm matrices, deliver antifungal agents, and disrupt biofilm structure. Various types of nanoparticles, including metallic, polymeric, lipid-based, and cyclodextrin-based, demonstrate enhanced biofilm penetration and antifungal activity. Their ability to generate reactive oxygen species, disrupt cell adhesion, and release antifungals in a controlled manner makes them ideal candidates for biofilm-targeted therapies. This review presents the current advancements in nanoparticle-based solutions, emphasizing the need for further research into their mechanisms of action, safety, and clinical application. By addressing the challenge of C. auris biofilms specifically, this review provides a critical synthesis of existing knowledge and identifies future directions for developing effective antifungal therapies using nanotechnology.

Small Intestinal Bacterial and Fungal Overgrowth: Health Implications and Management Perspectives

BACKGROUND/OBJECTIVES

Small Intestinal Bacterial Overgrowth (SIBO) and Small Intestinal Fungal Overgrowth (SIFO) are distinct yet often overlapping conditions characterized by an abnormal increase in microbial populations within the small intestine. SIBO results from an overgrowth of colonic bacteria, while SIFO is driven by fungal overgrowth, primarily involving Candida species. Both conditions present with nonspecific gastrointestinal (GI) symptoms such as bloating, abdominal pain, diarrhea, and malabsorption, making differentiation between SIBO and SIFO challenging. This review aims to elucidate the underlying mechanisms, risk factors, diagnostic challenges, and management strategies associated with SIBO and SIFO.

METHODS

A comprehensive review of current literature was conducted, focusing on the pathophysiology, diagnostic modalities, and therapeutic approaches for SIBO and SIFO.

RESULTS

SIBO is commonly associated with factors such as reduced gastric acid secretion, impaired gut motility, and structural abnormalities like bowel obstruction and diverticula. It is frequently diagnosed using jejunal aspirates (≥105 colony forming units (CFUs)/mL) or breath tests. In contrast, SIFO is linked to prolonged antibiotic use, immunosuppression, and gut microbiome dysbiosis, with diagnosis relying on fungal cultures from small intestinal aspirates due to the absence of standardized protocols.

CONCLUSION

The clinical overlap and frequent misdiagnosis of SIBO and SIFO highlight the need for improved diagnostic tools and a multidisciplinary approach to management. This review emphasizes the importance of understanding the mechanisms behind SIBO and SIFO, how they relate to other health outcomes, and potential management strategies to optimize patient care and therapeutic outcomes.

Uncovering the role of mitochondrial genome in pathogenicity and drug resistance in pathogenic fungi

Fungal infections are becoming more prevalent globally, particularly affecting immunocompromised populations, such as people living with HIV, organ transplant recipients and those on immunomodulatory therapy. Globally, approximately 6.55 million people are affected by invasive fungal infections annually, leading to serious health consequences and death. Mitochondria are membrane-bound organelles found in almost all eukaryotic cells and play an important role in cellular metabolism and energy production, including pathogenic fungi. These organelles possess their own genome, the mitochondrial genome, which is usually circular and encodes proteins essential for energy production. Variation and evolutionary adaptation within and between species' mitochondrial genomes can affect mitochondrial function, and consequently cellular energy production and metabolic activity, which may contribute to pathogenicity and drug resistance in certain fungal species. This review explores the link between the mitochondrial genome and mechanisms of fungal pathogenicity and drug resistance, with a particular focus on Cryptococcus neoformans and Candida albicans. These insights deepen our understanding of fungal biology and may provide new avenues for developing innovative therapeutic strategies.

Multi-computational screening identifies homovanillic acid as a potential SAP5 inhibitor against Candida albicans biofilms

This work aims to find inhibitors of SAP5, a virulence factor in Candida albicans polymicrobial biofilms. The methodology included docking simulations, MMGBSA calculations, and molecular dynamics simulations. Of the 107 phenolic acids retrieved from PubChem, 20 passed ADMET screening. The research finds homovanillic acid to be a possible SAP5 inhibitor, with a binding energy of -19.92 kcal/mol as shown by molecular docking and MMGBSA analysis. The compound showed favorable ADMET properties, indicating low toxicity and high drug-likeness. Molecular dynamics simulations over 100 nanoseconds confirmed stable protein-ligand interactions. These findings suggest homovanillic acid's potential in treating AMR-associated biofilms and establish a foundation for experimental validation. The study demonstrates how computational methods can accelerate the discovery of novel antifungal medicines targeting polymicrobial infections.

ML-AMPs designed through machine learning show antifungal activity against C. albicans and therapeutic potential on mice model with candidiasis

AIMS

C. albicans resistant strains have led to increasingly severe treatment challenges. Antimicrobial peptides with low resistance-inducing propensity for pathogens have been developed. A series of antimicrobial peptides de novo designed through machine learning by our research team were named ML-AMPs. In the present research, the antifungal activity of ML-AMPs against C. albicans and its therapeutic potential on Candidiasis mice model were studied.

MAIN METHODS

MTT methodology was performed to measure the minimum inhibitory concentrations. Absorbance photometry was utilized to evaluate the erythrocyte toxicity. Optical microscopy was operated to observe C. albicans hyphae. Crystal violet staining was employed to assess biofilm inhibition and reduction. Colony counting was performed to determine the time-kill kinetics. Scanning electron microscopy and fluorescent staining were used to investigate the underlying mechanism of antifungal action. Candidiasis mice model was established to evaluate the in vivo efficacy of ML-AMP2.

KEY FINDINGS

ML-AMPs exhibited strong anti-Candida activity, with minimum inhibitory concentrations against C. albicans ranging from 3.85 to 12.37 μg/mL. Notably, they exhibited robust fungicidal effects on fluconazole-resistant C. albicans. Moreover, they exhibited fast-killing kinetics, as well as low resistance potential. Additionally, ML-AMPs could effectively inhibit the formation of mycelium and biofilm, and more prominently, their ability to reduce biofilm was higher than that of fluconazole. ML-AMPS increased the permeability of C. albicans cell membrane and induced ROS accumulation. Among ML-AMPs, ML-AMP2 performed the best, which promoted the recovery of Candidiasis mice model.

SIGNIFICANCE

ML-AMP2 holds great promise as a candidate molecule for effectively treating drug-resistant C. albicans infections.

The Hidden Fortress: A Comprehensive Review of Fungal Biofilms with Emphasis on Cryptococcus neoformans

Biofilms are structurally organized communities of microorganisms that adhere to a variety of surfaces. These communities produce protective matrices consisting of polymeric polysaccharides, proteins, nucleic acids, and/or lipids that promote shared resistance to various environmental threats, including chemical, antibiotic, and immune insults. While algal and bacterial biofilms are more apparent in the scientific zeitgeist, many fungal pathogens also form biofilms. These surprisingly common biofilms are morphologically distinct from the multicellular molds and mushrooms normally associated with fungi and are instead an assemblage of single-celled organisms. As a collection of yeast and filamentous cells cloaked in an extracellular matrix, fungal biofilms are an extreme threat to public health, especially in conjunction with surgical implants. The encapsulated yeast, Cryptococcus neoformans, is an opportunistic pathogen that causes both pulmonary and disseminated infections, particularly in immunocompromised individuals. However, there is an emerging trend of cryptococcosis among otherwise healthy individuals. C. neoformans forms biofilms in diverse environments, including within human hosts. Notably, biofilm association correlates with increased expression of multiple virulence factors and increased resistance to both host defenses and antifungal treatments. Thus, it is crucial to develop novel strategies to combat fungal biofilms. In this review, we discuss the development and treatment of fungal biofilms, with a particular focus on C. neoformans.

A Novel Benzopyrone Derivative from Streptomyces chrestomyceticus ADP4 Inhibits Growth and Virulence Factors of Candida albicans

Antimicrobial resistance (AMR) poses a serious threat to human health globally. Expeditious discovery and development of new drugs has become indispensable for addressing this challenge. In this context, a novel benzopyrone derivative, designated as 82B1, has been isolated from S. chrestomyceticus strain ADP4. This compound exhibited significant inhibitory activity against different Candida species including C. albicans, C. tropicalis, C. krusei, C. parapsilosis and C. auris with minimum inhibitory concentration (MIC90) values in the concentration range of 25-125 µg/mL. The structure of 82B1 was elucidated through analyses of the spectral data obtained using liquid chromatography-tandem mass spectrometry (LCMS/MS), Nuclear Magnetic Resonance (NMR), Fourier Transform Infrared Spectroscopy (FTIR) and Ultraviolet (UV) spectroscopy, that led to its identity as 7, 13, 14-trihydroxy-6H-benzo-[c]-chromen-6-one8-[1'β-carboxycyclopentanyl]-2'β-[8'β-ethylcyclopentane]. It significantly inhibited the major virulence factors of C. albicans such as yeast to hyphae transition, biofilm formation, and secretion of hydrolytic enzymes at its subinhibitory concentrations. It did not display cytotoxicity on human hepatoblastoma cell line (HepG2 cells), signifying its potential as a candidate for anti-Candida drug development.

Blocking the shikimate pathway amplifies the impact of carvacrol on biofilm formation in Candida albicans

Candida albicans typically thrives in a commensal relationship with humans but is also an opportunistic fungal pathogen. As an opportunistic pathogen, C. albicans relies heavily on its ability to assimilate nutrients, for which it must compete with the host and other microorganisms. Amino acid biosynthesis, sensing, and uptake play pivotal roles in C. albicans growth and pathogenicity. C. albicans biosynthesizes aromatic amino acids and co-enzyme Q de novo through the shikimate pathway, including the Aro1, Aro2, and Aro7 enzymes, but also has amino acid transporters for uptake from the environment. Thus, antifungal approaches targeting aromatic amino acid biosynthesis must simultaneously inhibit amino acid biosynthesis and uptake. Herein, we investigate the plant-based antifungal, carvacrol, in conjunction with aromatic amino acid biosynthetic mutants, as a potential anti-candidal strategy. Growth of the WT, ARO2, and ARO7 strains were inhibited by 150 µg/mL carvacrol, whereas the ARO1 mutant was slightly more sensitive (with MIC 125 µg/mL). All repressed mutants exposed to carvacrol are partially rescued in the presence of para-aminobenzoic acid (PABA) (CoQ precursor), indicating that blocking the shikimate pathway impacts both aromatic amino acid and CoQ biosynthesis. Moreover, carvacrol at sublethal concentrations significantly inhibits ARO1 adhesion and hyphal formation, along with pre-attached and pre-formed hyphae, ultimately impacting biofilm metabolic activity and biomass accumulation and significantly reducing biofilm growth. In summary, carvacrol increases the sensitivity of C. albicans to ARO1 repression, with attenuated adhesion, hyphal formation, mycelial growth and biofilm formation, likely by blocking aromatic amino acid uptake.IMPORTANCEThe opportunistic pathogen Candida albicans remains the leading cause of candidemia and invasive candidiasis (IC), causing significant morbidity and mortality in immunocompromised patients. Our current arsenal of effective antifungal drugs is limited in number, mechanistic diversity, and efficacy, are cytotoxic and associated with antifungal resistance, necessitating the development of novel antifungals and combination therapies. Here, we show how simultaneously blocking the shikimate pathway, through ARO1 repression, and disrupting aromatic amino acid uptake by carvacrol prevent C. albicans biofilm formation. Thus, inhibitors of the Aro1 enzyme in combination with carvacrol are expected to shut down C. albicans biofilm formation and virulence.

Chemical characterization, antibacterial and antifungal activity of honey pots and pollen pots obtained from the stingless bee Tetragonisca angustula (Latreille, 1811)

This study aimed to determine the chemical composition of the ethanolic extracts of honey pots (EEHPTa) and pollen pots (EEPPTa) from the stingless bee Tetragonisca angustula, as well as to evaluate their antimicrobial activity against Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Candida albicans, and Candida tropicalis. The chemical composition was determined using HPLC-Q-TOF-MS/MS and HPLC-DAD, while antimicrobial assays were performed using the broth microdilution method. Eleven compounds were identified in EEHPTa and nine in EEPPTa, including cirsimaritin, 3'-prenylnaringenin, xanthohumol, lespedezaflavanone B, and 19α-hydroxyursolic acid. The extracts enhanced the action of norfloxacin against S. aureus (MIC reduced from 256 to 128 μg/mL). With gentamicin, EEHPTa reduced the MIC from 17.95 to 11.31 μg/mL, while EEPPTa reduced it to 12.69 μg/mL. Only EEHPTa was effective with ampicillin, reducing the MIC from 71.83 to 31.7 μg/mL. Against P. aeruginosa, EEHPTa decreased the MIC of gentamicin from 8 to 4 μg/mL, whereas EEPPTa exhibited an antagonistic effect. For E. coli, only EEPPTa reduced the MIC from 64 to 57.01 μg/mL. EEHPTa exhibited lower IC50 values against yeast (C. albicans: 65.47 μg/mL; C. tropicalis: 29.79 μg/mL) compared to EEPPTa (C. albicans: 820.7 μg/mL; C. tropicalis: 809.9 μg/mL). Both extracts enhanced the effect of fluconazole against C. albicans but showed no effect on the C. tropicalis strain. These findings highlight the therapeutic potential of the secondary metabolites in these extracts, reinforcing their importance in the development of new antimicrobial and antifungal strategies.

Zingerone effect against Candida albicans growth and biofilm production

BACKGROUND

The increasing resistance of Candida albicans biofilms underscores the urgent need for effective antifungals. This study evaluated the efficacy of zingerone and elucidated its mode of action against C. albicans ATCC 90028 and clinical isolate C1.

EXPERIMENTAL PROCEDURE

Minimum inhibitory concentrations (MICs) of zingerone were determined using CLSI methods against planktonic cells, biofilm formation, and yeast-to-hyphal transition. The mode of action was investigated through fluorescent microscopy, ergosterol assays, cell cycle analysis, and RT-PCR for gene expression.

KEY RESULTS

Zingerone inhibited planktonic growth and biofilm formation at in C. albicans ATCC 90028 and clinical isolate C1 at 2 mg/mL 4 mg/mL and 1 mg/mL and 2 mg/mL respectively. Treatment with the MIC concentration caused significant cell cycle arrest at the G0/G1 phase, halting proliferation in both the strains. Propidium iodide Staining revealed compromised membrane integrity in both the strains. Also, acridine orange and ethidium bromide dual staining showed increased dead cell proportions in C. albicans ATCC 90028. RT-PCR studies showed downregulation of BCY1, PDE2, EFG1, and upregulation of negative regulators NRG1, TUP1 disrupting growth and virulence pathways. Zingerone induced elevated reactive oxygen species (ROS) levels, triggering apoptosis, evidenced by DNA fragmentation and upregulation of apoptotic markers. It also inhibited ergosterol synthesis in a concentration-dependent manner, crucial for membrane integrity. Importantly, zingerone exhibited minimal hemolytic activity. In an in vivo silkworm model, zingerone demonstrated significant antifungal efficacy, protecting silkworms from infection. It also modulated stress response genes, highlighting its multifaceted action.

CONCLUSIONS

In vitro and in vivo findings confirm the potent antifungal efficacy of zingerone against C. albicans ATCC 90028 and clinical isolate C1, suggesting its promising potential as a therapeutic agent that warrants further exploration.

Evaluation of biofilm formation and antimicrobial susceptibility (drug resistance) of Candida albicans isolates

Candida albicans comprises over 80% of isolates from all forms of human candidiasis. Biofilm formation enhances their capacity to withstand therapeutic treatments. In addition to providing protection, biofilm formation by C. albicans enhances its pathogenicity. Understanding the fundamental mechanisms underlying biofilm formation is crucial to advance our understanding and treatment of invasive Candida infections. An initial screening of 57 Candida spp. isolates using CHROMagar Candida (CHROMagar) media revealed that 46 were C. albicans. Of these, 12 isolates (33.3%) had the capacity to form biofilms. These 12 isolates were subjected to multiple biochemical and physiological tests, as well as 18 S rRNA sequencing, to confirm the presence of C. albicans. Upon analysis of their sensitivity to conventional antifungal agents, the isolates showed varying resistance to terbinafine (91.6%), voriconazole (50%), and fluconazole (42%). Among these, only CD50 showed resistance to all antifungal agents. Isolate CD50 also showed the presence of major biofilm-specific genes such as ALS3, EFG1, and BCR1, as confirmed by PCR. Exposure of CD50 to gentamicin-miconazole, a commonly prescribed drug combination to treat skin infections, resulted in elevated levels of gene expression, with ALS3 showing the highest fold increase. These observations highlight the necessity of understanding the proteins involved in biofilm formation and designing ligands with potential antifungal efficacy.

Navigating dual-species fungal biofilms: The competitive and cooperative dynamics of Candidaalbicans

Research on microbial biofilms has primarily concentrated on bacterial-bacterial and bacterial-fungal interactions, leaving fungal-fungal dynamics underexplored. The present study examines interactions within dual-species fungal biofilms, with a particular emphasis on Candida albicans. The behavior and pathogenicity of this yeast are significantly influenced by its interactions with other fungal species in biofilms, where its ability to shift between yeast and hyphal forms contributes significantly to biofilm formation. These fungal species biofilms exhibit a complex interplay of synergistic cooperation and antagonistic competition, depending on the environmental context and resource availability. Understanding these interactions is essential for advancing our knowledge of fungal biofilm.

Candidiasis: Insights into Virulence Factors, Complement Evasion and Antifungal Drug Resistance

Invasive fungal infections constitute a substantial global health burden, with invasive candidiasis representing approximately 70% of reported cases worldwide. The emergence of antifungal resistance among Candida species has further exacerbated this challenge to healthcare systems. Recent epidemiological studies have documented a concerning shift towards non-albicans Candida species, exhibiting reduced antifungal susceptibility, in invasive candidiasis cases. The complement system serves as a crucial first-line defence mechanism against Candida infections. These fungal pathogens can activate the complement cascade through three conventional pathways-classical, lectin, and alternative-in addition to activation through the coagulation system. While these pathways are initiated by distinct molecular triggers, they converge at C3 convertase formation, ultimately generating biologically active products and the membrane attack complex. Candida species have evolved sophisticated mechanisms to evade complement-mediated host defence, including the masking of cell wall components, proteolytic cleavage and inhibition of complement proteins, recruitment of complement regulators, and acquisition of host proteins. This review examines the intricate interplay between Candida species and the host complement system, with emphasis on complement evasion strategies. Furthermore, we highlight the importance of exploring the crosstalk between antifungal resistance and immune evasion strategies employed by Candida species. Understanding these interactions may facilitate the development of novel therapeutic approaches and strategies to overcome treatment failures in Candida species infections.

Retinoids as Alternative Antifungal Agents Against Candida albicans: In Vitro and In Silico Evidence

Candida albicans (C. albicans) is the most common pathogen responsible for a wide spectrum of human infections ranging from superficial mucocutaneous mycoses to systemic life-threatening diseases. Its main virulence factors are the morphological transition between yeast and hyphal forms and the ability to produce biofilm. Novel antifungal strategies are required given the severity of systemic candidiasis, especially in immunocompromised patients, and the lack of effective anti-biofilm treatments. We previously demonstrated that all-trans retinoic acid (ATRA), an active metabolite of vitamin A, exerted an inhibitory effect on Candida growth, yeast-hyphal transition and biofilm formation. Here, we further investigated the possible anti-Candida potential of trifarotene and tazarotene, which are the other two molecules belonging to the retinoid family, compared to ATRA. The results indicate that both drugs were able to suppress Candida growth, germination and biofilm production, although trifarotene was proven to be more effective than tazarotene, showing effectiveness comparable to ATRA. In silico studies suggest that all three retinoids may exert antifungal activity through their molecular interactions with the heat shock protein (Hsp) 90 and 14α-demethylase of C. albicans. Moreover, interactions between retinoids and ergosterol have been observed, suggesting that those compounds have great potential against C. albicans infections.

Relationships Between Candida auris and the Rest of the Candida World-Analysis of Dual-Species Biofilms and Infections

In this study, we investigated the interactions between Candida auris and C. albicans, C. tropicalis, C. glabrata, and C. krusei in mixed infections. Initially, these interactions were studied qualitatively and quantitatively in dual-species biofilms formed in vitro. The MTT assays, determination of the total CFU/mL, and SEM analysis showed that C. auris interacted differentially with the other Candida spp. during the dual-species biofilm formation. Depending on the stage of the biofilm development, C. auris was found to be a particularly dominant species during its interaction with the C. krusei biofilms but significantly submissive in the C. auris-C. albicans biofilms. These studies were then extended to in vivo host models of experimental candidiasis. G. mellonella larvae were inoculated with monotypic and heterotypic suspensions of Candida. The survival rates and quantification of fungal cells in the hemolymph showed that the highest mortality was exhibited by larvae in the C. auris-C. albicans co-infection (100% mortality after 36 h). The CFU/mL values of C. auris from the larval hemolymph were lower in the interactive groups compared to the mono-species group. As a newly emerging species, C. auris persists in environments in the presence of other Candida species and is involved in both competitive and noncompetitive interactions with other Candida species during biofilm formation and development of experimental candidiasis.

Characterization and enhanced antibiofilm activity of Annona muricata extract in combination with fluconazole against Candida albicans

Introduction

Candida albicans biofilm formation is a significant contributor to antifungal resistance, necessitating new treatment strategies. Annona muricata Lin., a traditional herbal remedy, has shown promise in combating microbial infections. The purpose of this study was to assess the antibiofilm activity of the methanol extract of A. muricata leaves alone or with the addition of fluconazole against C. albicans.

Methods

Phytochemicals from the methanol extract were analyzed by LC-MS, the XTT assay was used for metabolic activity, and morphological characteristics were examined using scanning electron microscopy (SEM). Molecular docking screening of identified compounds in A. muricata methanol leaves extract against a Sap3 receptor (PDB: 2H6T) was also performed.

Results

The LC-MS analysis detected 17 possible phytochemicals. The methanol extract showed a dose-dependent inhibition of biofilm formation, with maximum inhibition of ~60% observed at 240 μg/ml, and inhibition by fluconazole increased from 32% to 76% as the concentration increased from 15 to 240 μg/ml. The combination of A. muricata and fluconazole increased the inhibition significantly, from 74% to 78% at 15 μg/ml to 240 μg/mL, respectively. SEM of control and treated C. albicans biofilms showed an altered morphology and loss of cell integrity by the combination, corroborating the findings. Plant phytochemicals also possess high binding affinity (-9.7 to 8.0 kcal/mol, respectively) for the Sap3 enzyme and may therefore have therapeutic potential against C. albicans.

Conclusion

Consequently, the findings indicate that compounds in the A. muricata methanol extract may function in concert with fluconazole at sub-inhibitory concentrations to suppress C. albicans biofilm formation. This finding paves the way for the formulation and development of antifungal treatment regimens that may limit the development of fluconazole resistance employing this plant part.

The biofilm produced by Cryptococcus neoformans protects the fungus from the antifungal and anti-melanin effects of cyclosporine

Understanding Cryptococcus neoformans pathogenesis requires a detailed analysis of the various virulence factors that contribute to its ability to cause disease. Cyclosporine, calcineurin inhibitor, impairs C. neoformans production of a polysaccharide capsule and secretion of urease, which are critical for cryptococcal pathogenesis. Two particularly important virulence factors are the production of cell wall melanin and formation of biofilm. In this study, we investigated cyclosporine's effects on melanin production and biofilm formation in C. neoformans. Initially, we examined melanin production in planktonic cells treated with cyclosporine using an L-DOPA containing melanin-inducing medium. Visual inspection and optical microscopy revealed a notable reduction in the characteristic dark coloration of cultures treated with cyclosporine, which indicate decreased melanin production in daughter cells compared to mother cells. Spectrophotometric analysis also demonstrated a significantly altered ultraviolet-visible (UV/vis) absorption spectra in cyclosporine-treated yeast cells, indicative of structural changes in melanin. Additionally, cyclosporine-treated cells exhibited reduced conductance (P-value < 0.0001), suggesting altered cellular ionic properties. The impact of cyclosporine on biofilm formation and mature biofilm disruption was also assessed. Despite cyclosporine's efficacy in modifying virulence factors during planktonic growth, cyclosporine did not inhibit biofilm formation or melanization under biofilm growth conditions, nor did it disrupt mature biofilms in terms of biomass or metabolic activity. However, there was a significant reduction in extracellular matrix production in cyclosporine-treated non-melanized biofilms. Our findings underscore the complex interplay between cyclosporine and C. neoformans, highlighting its differential effects on melanization and biofilm dynamics, which provides new insights into the shortcomings of cyclosporin for combatting cryptococcosis and informs pathways for future therapeutic strategies against cryptococcosis.

Antifungal Properties of Polycephalomyces nipponicus (Ascomycetes) against Candida albicans: Potential for Novel Therapeutic Development

Candida albicans has the potential to turn pathogenic and cause mild to severe infections, particularly in people with weakened immune systems. Novel therapeutics are required due to its morphological alterations, biofilm development, and resistance to antifungal drugs. Polycephalomyces nipponicus, a traditional East Asian medicinal fungus, has shown potential as an antifungal agent. In this study, 15 P. nipponicus isolates were cultivated and their mycelial extracts were evaluated against C. albicans NCYC854 using agar well diffusion, broth microdilution, scanning electron microscope (SEM), and time-kill assays. Eight isolates exhibited significant antifungal activity, with inhibition zones from 11.25 ± 1.50 mm to 18 ± 0.82 mm, notably Cod-MK1209 surpassing amphotericin B. Minimum inhibitory concentrations (MICs) and minimum fungicidal concentrations (MFCs) ranged from 125 to 500 μg/mL, with extracts from Cod-MK1206 and Cod-MK1209 showing the lowest MFC at 125 μg/mL. The results of time-kill experiments showed fungistatic effects by drastically lowering viable cell populations at 1ȕ and 2ȕ MIC concentrations within 24 h. The SEM analysis also indicated evidence of degradation to the cellular wall and membrane. These findings highlight the potential of P. nipponicus extracts as powerful antifungal medicines that target C. albicans selectively. Further research efforts have to focus on the identification and description of bioactive components, enhancement of extraction techniques, and advancement towards preclinical and clinical studies to validate their potential for therapeutic use.

In silico-driven identification and experimental confirmation of antifungal proteins (AFPs) against Candidaalbicans

Mycoses infect millions of people annually across the world. The most common mycosis agent, Candida albicans is responsible for a great deal of illness and death. C. albicans infection is becoming more widespread and the current antifungals polyenes, triazoles, and echinocandins are less efficient against it. Investigating antifungal peptides (AFPs) as therapeutic is gaining momentum. Therefore, we used MALDI-TOF/MS analysis to identify AFPs and protein-protein docking to analyze their interactions with the C. albicans target protein. Some microorganisms with strong antifungal action against C. albicans were selected for the isolation of AFPs. Using MALDI-TOF/MS, we identified 3 AFPs Chitin binding protein (ACW83017.1; Bacillus licheniformis), the bifunctional protein GlmU (BBQ13478.1; Stenotrophomonas maltophilia), and zinc metalloproteinase aureolysin (BBA25172.1; Staphylococcus aureus). These AFPs showed robust interactions with C. albicans target protein Sap5. We deciphered some important residues in identified APFs and highlighted interaction with Sap5 through hydrogen bonds, protein-protein interactions, and salt bridges using protein-protein docking and MD simulations. The three discovered AFPs-Sap5 complexes exhibit different levels of stability, as seen by the RMSD analysis and interaction patterns. Among protein-protein interactions, the remarkable stability of the BBQ25172.1-2QZX complex highlights the role of salt bridges and hydrogen bonds. Identified AFPs could be further studied for developing successful antifungal candidates and peptide-based new antifungal therapeutic strategies as fresh insights into addressing antifungal resistance also.

Calcofluor White-Phosphatidylethanolamine Conjugate-Enhanced Ethosomal Delivery of Voriconazole for Targeting Candida albicans

Introduction

The increasing prevalence of systemic fungal infections, especially among immunocompromised individuals, highlights the need for advancements in targeted and effective antifungal treatments. This study presents a novel nanomaterial, CFW-phosphatidylethanolamine conjugate (CFW-PEc), designed to enhance the delivery and efficacy of antifungal agents by targeting fungal cell walls through specific chitin binding. Ethosomes, lipid-based nanocarriers known for their ability to improve drug delivery across skin and cell membranes, were utilized in this study.

Methods

The physicochemical characteristics of voriconazole-loaded CFW-PEc ethosomes (CFW-PEc-VRC-ethosomes) were examined, including particle size, zeta potential, and entrapment efficiency. Antifungal efficacy of CFW-PEc-VRC-ethosomes was evaluated, including antifungal activity in vitro, CFW-PEc-ethosomes cellular uptake, and models of animal infection and imaging analyses.

Results

In vitro experiments demonstrated a concentration-dependent inhibition of C. albicans growth by CFW-PEc, with cell inhibition rates reaching nearly 100% at 256 μM. In vivo investigations confirmed a 5-fold reduction in fungal burden in the liver and a 7.8-fold reduction in the kidney compared to the control group following treatment with CFW-PEc (0.1 μM)-VRC-ethosomes. Imaging analyses also confirmed the extended tissue retention of fluorescent dye-loaded CFW-PEc-ethosomes in mice, further underscoring their potential for clinical use.

Discussion

The targeted delivery of antifungal medications via ethosomes coated with CFW-PEc presents a promising strategy to improve antifungal effectiveness while reducing adverse effects, marking a significant advancement in fungal infection therapy.

Antifungal activities of Equol against Candida albicans in vitro and in vivo

Candida albicans is an opportunistic fungal pathogen that can cause systemic infections in immunocompromised individuals. Morphological transition and biofilm formation are major virulence factors of C. albicans. Moreover, biofilm enhances resistance to antifungal agents. Therefore, it is urgent to identify new and effective compounds to target the biofilm of C. albicans. In the present study, the antifungal activities of equol against C. albicans were investigated. In vitro, the microdilution analysis and spot assay result showed that equol exhibited potent inhibitory activities against C. albicans. Further investigations confirmed that the antifungal effects of equol involved interference with the transition from yeast to hypha and biofilm formation of C. albicans. In addition, transcriptome sequencing and reverse transcription-quantitative PCR (qRT-PCR) analysis showed that equol significantly downregulated the expression of several genes in the Ras1-cAMP-PKA pathway related to hyphae and biofilm formation and significantly upregulated the expression of the negative transcriptional repressors RFG1 and TUP1. Moreover, equol effectively reduced the production of cAMP, a key messenger in the Ras1-cAMP-PKA pathway, while supplementation with cAMP partly rescued the equol-induced defects in hyphal development. Furthermore, in a mouse model of systemic candidiasis (SC), equol treatment significantly decreased the fungal burden (liver, kidneys, and lung) in mice and local tissue damage, while enhancing the production of interleukin-10 (IL-10). Together, these findings confirm that equol is a potentially effective agent for treatment of SC.

Resveratrol-coated gold nanorods produced by green synthesis with activity against Candida albicans

Candida albicans is an opportunistic yeast capable of causing a wide range of mucosal, cutaneous, and systemic infections. However, therapeutic strategies are limited to a few antifungal agents. Inorganic nanoparticles have been investigated as carrier systems for antifungals as potential new treatments. In this study, we focused on the antifungal activity of gold nanorods, a specific rod-shaped gold nanoparticle, produced by green synthesis using resveratrol as a metal-reducing agent. The synthesis method resulted in stable control nanoparticles (AuNp) and resveratrol-coated gold nanoparticles (AuNpRSV) with medium sizes of 32.4 × 15.9 nm for AuNp, and 33.5 × 15.3 nm for AuNpRSV. Both AuNp and AuNpRSV inhibited the C. albicans grown at 2.46 µg/mL, exhibited fungicidal effects at 4.92 µg/mL, and significantly decreased filamentation, biofilm viability, reactive oxygen species production and ergosterol levels of C. albicans. In addition, exposure to AuNpRSV reduced the ability of C. albicans to grow in the presence of cell membrane stressors. Transmission electron microscopy revealed enlargement of the cell wall and retraction of the cell membrane after treatment with AuNp and AuNpRSV. Promisingly, in vivo toxicity analysis demonstrated that both nanoparticles maintained the full viability of Galleria mellonella larvae at 49.20 µg/mL. In conclusion, both gold nanoparticles exhibited antifungal activity; however, these effects were enhanced by AuNpRSV. Altogether, AuNps and AuNpRSVs are potential antifungal agents for the treatment of C. albicans infections.

Identification of fungal pathogens among COVID-19 and non COVID-19 cases in Bhaktapur hospital, Nepal

OBJECTIVES

Patients with coronavirus disease 2019 (COVID-19) are at increased risk of opportunistic fungal infections. This study aims to identify fungal pathogens among COVID positive and negative patients, assess their antifungal susceptibility and evaluate biofilm forming ability of Candida spp. A cross-sectional study was conducted among sputum samples from 135 COVID positive and 101 COVID negative cases. Fungal pathogens were identified by conventional culture methods. Antifungal susceptibility test of Candida isolates was done by disc diffusion method and biofilm production by microtiter plate method.

RESULTS

The prevalence of fungal pathogens among COVID-positive and negative cases was 6.70% and 22.77% respectively. In COVID positive cases, Candida albicans (33.33%) was predominantly followed by Aspergillus flavus 2(22.22%) and Candida tropicalis, Mucor spp. and Aspergillus fumigatus. In COVID negative cases, Candida albicans (69.60%) prevailed followed by Trichosporon spp., Candida parapsilosis, Mucor and Alternaria. Age and gender were not associated with fungal infection. Most Candida spp. were susceptible to miconazole but resistant to ketoconazole. To the best of our knowledge, this study represents the first report from Nepal on critical and high priority fungal pathogens categorized by WHO. With fungal infections on the rise, enhanced clinical vigilanceand antifungal susceptibility testing are warranted.

Pullulan nanoparticles inhibit the pathogenicity of Candida albicans by regulating hypha-related gene expression

Candida albicans is a prevalent opportunistic pathogenic fungus that resides in the skin and gastrointestinal (GI) tract of humans. Under specific conditions, C. albicans cells transition from a commensal to a pathogenic state, leading to both superficial and invasive infections. Although systemic candidiasis poses a life-threatening risk, a limited number of antifungal drugs are employed for its treatment. Moreover, the emergence of resistant strains to antifungal agents underscores the pressing need for new treatment options. In this study, we propose the use of polysaccharide nanoparticles as a strategy for treating candidiasis. We synthesized phthalic pullulan nanoparticles (PPNPs) and examined their ability to inhibit the pathogenicity of C. albicans. We observed that PPNPs inhibit hyphal growth, adhesion to abiotic surfaces, and biofilm formation of C. albicans in a dose-dependent manner. This inhibitory effect is mediated by transcriptional modulation, particularly the downregulation of hypha-related genes and the upregulation of stress-responsive genes, involving the Ras/cAMP/PKA signaling pathway. Furthermore, we observed that PPNPs inhibit the adhesion of C. albicans to human epithelial cells without inducing toxicity in human cells. In addition, PPNPs inhibited the in vivo pathogenicity of C. albicans in Caenorhabditis elegans, suggesting an antagonistic effect on candidiasis. Our findings suggest that PPNPs exhibit inhibitory effects on C. albicans biofilm formation and in vivo pathogenicity, indicating their potential as a novel therapeutic agent for candidiasis.

IMPORTANCE

The pathogenic process of Candida albicans, the primary causative species of candidiasis, involves hyphal growth, biofilm formation, and secretion of virulence factors. Of these factors, the biofilm, created by the secretion of extracellular matrix from adherent cells, shields cells from external threats, enabling them to withstand high concentrations of antifungal agents. Therefore, suppressing biofilm formation is a crucial aspect of combating candidiasis. This study developed phthalic pullulan nanoparticles (PPNPs) as a novel material for inhibiting C. albicans' pathogenicity. PPNPs were internalized within Candida cells and reduced pathogenicity at the gene expression level, resulting in reduced in vitro biofilm formation, adhesion to human cells, and mortality of infected Caenorhabditis elegans. Moreover, PPNPs exhibited these effects without toxicity to human cells and host animals. These findings not only indicate that PPNPs can be employed to hinder in vitro biofilm formation but also suggest their potential as a novel treatment for candidiasis.

Development and characterization of nanoemulsions containing Lippia origanoides Kunth essential oil and their antifungal potential against Candida albicans

AIMS

Nanoemulsions based on plant essential oils have shown promise as alternatives against fungal pathogens by increasing the solubility and bioavailability of the active compounds of essential oils, which can improve their efficacy and safety. In the present study, we aimed to prepare and characterize nanoemulsions of Lippia origanoides essential oil, and analyze their antifungal activity against C. albicans in planktonic and biofilm form. Additionally, we sought to verify their cytotoxicity.

METHODS AND RESULTS

Alginate nanoemulsions were prepared with different concentrations of essential oil, sunflower oil, and surfactant to investigate ideal formulations regarding stability and antifungal efficiency. The results showed the nanoemulsions remained stable for longer than 60 days, with acidic pH, particle sizes ranging from 180.17 ± 6.86 nm to 497.85 ± 253.50 nm, zeta potential from -60.47 ± 2.25 to -43.63 ± 12, and polydispersity index from 0.004 to 0.622. The photomicrographs revealed that the addition of sunflower oil influenced the formation of the particles, forming nanoemulsions. The antifungal results of the essential oil and nanoemulsions showed that the MIC ranged from 0.078 to 0.312 mg ml-1. The nanoemulsions were more effective than the free essential oil in eradicating the biofilm, eliminating up to 89.7% of its mass. With regard to cytotoxicity, differences were found between the tests with VERO cells and red blood cells, and the nanoemulsions were less toxic to red blood cells than the free essential oil.

CONCLUSIONS

These results show that nanoemulsions have antifungal potential against strains of C. albicans in planktonic and biofilm forms.

Antimicrobial peptide AMP-17 induces protection against systemic candidiasis and interacts synergistically with fluconazole against Candida albicans biofilm

Candida albicans, a common commensal and opportunistic fungal pathogen in humans, can occasionally progress to disseminated candidiasis which is a serious condition with a high morbidity and fatality rate. The emergence of drug-resistant fungal strains compels us to look for an efficient treatment solution. Our earlier studies have demonstrated that the unique antimicrobial peptide AMP-17 from Musca domestica has a strong antifungal impact on C. albicans in vitro. Here, we verified the therapeutic effects of AMP-17 on systemic candidiasis in vivo and the peptide interacts with fluconazole, a common antifungal medication, to treat systemic candidiasis. In the disseminated candidiasis model of Galleria mellonella and mice challenged with C. albicans, AMP-17 increased the survival rates of infected larvae and mice to 66.7 and 75%, respectively. Furthermore, the peptide lowered the load of C. albicans in the infected larvae and the kidneys of the mice by nearly 90%. Additional histological examination and measurements of plasma cytokines showed that the injection of AMP-17 markedly reduced the inflammatory response and balanced cytokine expression. Furthermore, checkerboard micro dilution experiments demonstrated that AMP-17 and fluconazole worked in synergy to inhibit C. albicans in the biofilm mode. According to morphological studies, AMP-17 and fluconazole together decreased the production of hyphae throughout the C. albicans biofilm formation process, loosening the mature biofilms' structure and lowering the amount of carbohydrates in the extracellular matrix (ECM) of the biofilms. Taken together, these results showed that AMP-17 would be a viable treatment for systemic candidiasis and might be a different approach to combating Candida biofilm, either by itself or in conjunction with fluconazole.

Anti-fungal peptides: an emerging category with enthralling therapeutic prospects in the treatment of candidiasis

Candida infections, particularly invasive candidiasis, pose a serious global health threat. Candida albicans is the most prevalent species causing candidiasis, and resistance to key antifungal drugs, such as azoles, echinocandins, polyenes, and fluoropyrimidines, has emerged. This growing multidrug resistance (MDR) complicates treatment options, highlighting the need for novel therapeutic approaches. Antifungal peptides (AFPs) are gaining recognition for their potential as new antifungal agents due to their diverse structures and functions. These natural or recombinant peptides can effectively target fungal virulence and viability, making them promising candidates for future antifungal development. This review examines infections caused by Candida species, the limitations of current antifungal treatments, and the therapeutic potential of AFPs. It emphasizes the importance of identifying novel AFP targets and their production for advancing treatment strategies. By discussing the therapeutic development of AFPs, the review aims to draw researchers' attention to this promising field. The integration of knowledge about AFPs could pave the way for novel antifungal agents with broad-spectrum activity, reduced toxicity, targeted action, and mechanisms that limit resistance in pathogenic fungi, offering significant advancements in antifungal therapeutics.

An Injectable Living Hydrogel with Embedded Probiotics as a Novel Strategy for Combating Multifaceted Pathogen Wound Infections

Wound infections pose a significant challenge in healthcare, and traditional antibiotic treatments often result in the development of resistant pathogens. Addressing this gap, ProGel is introduced, a living hydrogel created by entrapping probiotic Lactobacillus plantarum as a therapeutic component within a gelatin matrix. With a double-syringe system, ProGel can be easily mixed and applied, conforming swiftly to any wound shape and forming hydrogel in situ. It also demonstrates robust mechanical and self-healing properties owing to the Schiff-base bonds. ProGel sustains more than 80% viability of the entrapped L. plantarum while restricting their escape from the hydrogel. After a week of storage, more than 70% viability of the entrapped L. plantarum is preserved. Importantly, ProGel exhibits broad-spectrum antimicrobial efficacy against pathogens commonly associated with wound infections, i.e., Pseudomonas aeruginosa (7Log reduction), Staphylococcus aureus (3-7Log reduction), and Candida albicans (40-70% reduction). Moreover, its cytocompatibility is affirmed through coculture with human dermal fibroblasts. The effectiveness of ProGel is further highlighted in more clinically relevant tests on human skin wound models infected with P. aeruginosa and S. aureus, where it successfully prevents the biofilm formation of these pathogens. This study showcases an injectable living hydrogel system for the management of complex wound infections.

Vaginal candidiasis prevalence, associated factors, and antifungal susceptibility patterns among pregnant women attending antenatal care at bule hora university teaching hospital, Southern Ethiopia

BACKGROUND

Vulvovaginitis is common in women of reproductive age group characterized by purulent white discharge. The incidence of vulvovaginitis has risen recently due to the resistance of Candida species to commonly used antifungal agents and recurrent infections.

OBJECTIVE

The study aimed to determine the prevalence, associated factors, and antifungal susceptibility patterns of vaginal candidiasis among pregnant women attending Bule Hora University Teaching Hospital.

METHODS

A hospital-based cross-sectional study was conducted from May 2023 to August 2023. Using systematic random sampling, 317 pregnant women participated in the study. Sabouraud Dextrose Agar and Chromogenic Candida Differential Agar were used to isolate and identify Candida species from clinical samples. Antifungal susceptibility was performed using a modified disc diffusion method. Epi data version 4.6 was used for data entry and Statistical Packages for Social Sciences version 25 was used for statistical analysis. A P-value < 0.05 was declared statistically significant.

RESULT

The prevalence of vaginal candidiasis was 26.8% (95%, CI 21.9-31.72%). History of using contraceptives (AOR = 5.03, 95%CI, 1.21-11.37), past vaginal candidiasis (AOR = 6, 95%CI, 1.61-12.92), pregnant women infected with human immunodeficiency virus (HIV) (AOR = 4.24, 95%CI, 1.23-14.14), diabetic mellitus (AOR = 2.17, 95%CI, 1.02-4.64), history of antibiotic use (AOR = 3.55, 95%CI, 1.67-12.75), pregnant women in third trimester (AOR = 8.72, 95%CI, 1.30-23.07), were the significantly associated factors for vaginal candidiasis. The study revealed that itraconazole, amphotericin B, and miconazole were the most effective antifungal drugs for all Candida isolates.

CONCLUSION

The present study has identified a high prevalence of vaginal candidiasis among pregnant women. The isolated Candida species showed resistance to fluconazole, ketoconazole, and clotrimazole. Therefore, healthcare providers should increase awareness of the risks of Candida infections to reduce Candida species among pregnant women. Physicians should prescribe suitable medications based on antifungal drug test outcomes to treat pregnant women with vaginal candidiasis.

Nanomaterial-based therapeutics for enhanced antifungal therapy

The application of nanotechnology in antifungal therapy is gaining increasing attention. Current antifungal drugs have significant limitations, such as severe side effects, low bioavailability, and the rapid development of resistance. Nanotechnology offers an innovative solution to address these issues. This review discusses three key strategies of nanotechnology to enhance antifungal efficacy. Firstly, nanomaterials can enhance their interaction with fungal cells via ingenious surface tailoring of nanomaterials. Effective adhesion of nanoparticles to fungal cells can be achieved by electrostatic interaction or specific targeting to the fungal cell wall and cell membrane. Secondly, stimuli-responsive nanomaterials are developed to realize smart release of drugs in the specific microenvironment of pathological tissues, such as the fungal biofilm microenvironment and inflammatory microenvironment. Thirdly, nanomaterials can be designed to cross different physiological barriers, effectively addressing challenges posed by skin, corneal, and blood-brain barriers. Additionally, some new nanomaterial-based strategies in treating fungal infections are discussed, including the development of fungal vaccines, modulation of macrophage activity, phage therapy, the application of high-throughput screening in drug discovery, and so on. Despite the challenges faced in applying nanotechnology to antifungal therapy, its significant potential and innovation open new possibilities for future clinical antifungal applications.

ASLdC3: A Derivative of Acidic Sophorolipid Disrupts Mitochondrial Function, Induces ROS Generation, and Inhibits Biofilm Formation in Candida albicans

Fungal infections account for more than 140 million cases of severe and life-threatening conditions each year, causing approximately 1.7 million deaths annually. Candida albicans and related species are the most common human fungal pathogens, causing both superficial (mucosal and cutaneous) and life-threatening invasive infections (candidemia) with a 40-75% mortality rate. Among many virulence factors of Candida albicans, morphological transition from yeast to hyphae, secretion of hydrolytic enzymes, and formation of biofilms are considered to be crucial for pathogenicity. However, the arsenals for the treatment against these pathogens are restricted to only a few classes of approved drugs, the efficacy of which is being compromised by host toxicity, fungistatic activity, and the emergence of drug resistance. In this study, we have described the development of a molecule, exhibiting excellent antifungal activity (MIC 8 μg/mL), by tailoring acidic sophorolipids with aryl alcohols via enzyme catalysis. This novel derivative, ASLdC3, is a surface-active compound that lowers the surface tension of the air-water interface up to 2-fold before reaching the critical micelle concentration of 25 μg/mL. ASLdC3 exhibits excellent antibiofilm properties against Candida albicans and other nonalbicans Candida species. The molecule primarily exhibits its antifungal activity by perturbing mitochondrial function through the alteration of the mitochondrial membrane potential (MMP) and generation of reactive oxygen species (ROS). The ROS damages fungal cell membrane function and cell wall integrity, eventually leading to cell death. ASLdC3 was found to be nontoxic in in vitro assay and nonhemolytic. Besides, it does not cause toxicity in the C. elegans model. Our study provides a valuable foundation for the potential of acidic sophorolipid as a nontoxic, biodegradable precursor for the design and synthesis of novel molecules for use as antimicrobial drugs as well as for other clinical applications.

Virulence-Related Genes Expression in Planktonic Mixed Cultures of Candida albicans and Non-Albicans Candida Species

INTRODUCTION

Candida albicans is the most common opportunistic pathogen causing fungal infections worldwide, especially in high-risk patients. Its pathogenicity is related to virulence factors gene expression, such as hyphal growth (HWP1), cell adhesion (ALS3), and protease secretion (SAP1) during infection spreading mechanisms. In recent years, an increase in non-albicans Candida infections has been reported, which may present coinfection or competitive interactions with C. albicans, potentially aggravating the patient's condition. This study aims to evaluate the expression of genes related to virulence factors of C. albicans and non-albicans Candida during planktonic stage.

METHODS

C. albicans (ATCC MYA-3573) as well as with three clinical strains (C. albicans DCA53, C. tropicalis DCT6, and C. parapsilosis DCP1) isolated from blood samples, were grown in 24-well plates at 37°C for 20 h, either in monocultures or mixed cultures. Quantitative real-time polymerase chain reaction was used to evaluate the expression levels of the genes HWP1, ALS3, and SAP1 in cells collected during the planktonic stage. In addition, hyphal filamentation was observed using a Scanning Electron Microscope.

RESULTS

The overexpression of HWP1 and ASL3 genes in mixed growth conditions between C. albicans and non-albicans Candida species suggests a synergistic relationship as well as an increased capacity for hyphal growth and adhesion. In contrast, C. parapsilosis versus C. tropicalis interaction shows an antagonistic relationship during mixed culture, suggesting a decreased virulence profile of C. parapsilosis during initial coinfection with C. tropicalis.

CONCLUSION

The expression of HWP1, ALS3, and SAP1 genes associated with virulence factors varies under competitive conditions among species of the genus Candida during planktonic stage.

Evaluation of antifungal spectrum of Cupferron against Candida albicans

Candida albicans is an opportunistic yeast accounting for about 50-90 % of all cases of candidiasis in humans, ranging from superficial to systemic potentially life-threatening infections. The presence of several virulence factors, including biofilm, hyphal transition, and proteolytic enzymes production, worsens the fungal infections burden on healthcare system resources. Hence, developing new bioactive compounds with antifungal activity is a pressing urgence for the scientific community. In this perspective, we evaluated the anti-Candida potential of the N-Nitroso-N-phenylhydroxylamine ammonium salt (cupferron) against standard and clinical C. albicans strains. Firstly, the in vitro cytotoxicity of cupferron was checked in the range 400-12.5 μg/mL against human microglial cells (HMC-3). Secondly, its antifungal spectrum was explored via disk diffusion test, broth-microdilution method, and time-killing curve analysis, validating the obtained results through scanning electron microscopy (SEM) observations. Additionally, we evaluated the cupferron impact on the main virulence determinants of Candida albicans. At non-toxic concentrations (100-12.5 μg/mL), the compound exerted interesting anti-Candida activity, registering a minimum inhibitory concentration (MIC) between 50 and 100 μg/mL against the tested strains, with a fungistatic effect until 100 μg/mL. Furthermore, cupferron was able to counteract fungal virulence at MIC and sub-MIC values (50-12.5 μg/mL). These findings may propose cupferron as a new potential antifungal option for the treatment of Candida albicans infections.

New arsenals for old armour: Biogenic nanoparticles in the battle against drug-resistant Candidaalbicans

Candida albicans is a common commensal fungus and fourth most frequent causative agent of nosocomial infections including life-threatening invasive candidiasis in humans. The effectiveness of present antifungal therapies using azoles, polyenes, flucytosine and echinocandins has plateaued in managing fungal infections. The limitations of these antifungal drugs are related to polymorphic morphology, biofilm formation, emergence of drug-resistant strains and production of several virulence factors. Development of new antifungal agents, which can particularly afflict multiple cellular targets and limiting evolving resistant strains are needed. Recently, metal nanoparticles have emerged as a source of new antifungal agents for antifungal formulations. Furthermore, green nanotechnology deals with the use of biosynthetic routes that offer new avenue for synthesizing antifungal nanoparticles coupled with less toxic chemical inventory and environmental sustainability. This article reviews the recent developments on C. albicans pathogenesis, biofilm formation, drug resistance, mode of action of antifungal drugs and antifungal activities of metal nanoparticles. The antifungal efficacy and mode of action of metal nanoparticles are described in the context of prospective therapeutic applications.

Exploring the Antibiofilm Effect of Sertraline in Synergy with Cinnamomum verum Essential Oil to Counteract Candida Species

The emergence and spread of drug-resistant pathogens, resulting in antimicrobial resistance, continue to compromise our capability to handle commonly occurring infectious diseases. The rapid global spread of multi-drug-resistant pathogens, particularly systemic fungal infections, presents a significant concern, as existing antimicrobial drugs are becoming ineffective against them. In recent decades, there has been a notable increase in systemic fungal infections, primarily caused by Candida species, which are progressively developing resistance to azoles. Moreover, Candida species biofilms are among the most common in clinical settings. In particular, they adhere to biomedical devices, growing as a resilient biofilm capable of withstanding extraordinarily high antifungal concentrations. In recent years, many research programs have concentrated on the development of novel compounds with possible antimicrobial effects to address this issue, and new sources, such as plant-derived antimicrobial compounds, have been thoroughly investigated. Essential oils (EOs), among their numerous pharmacological properties, exhibit antifungal, antibacterial, and antiviral activities and have been examined at a global scale as the possible origin of novel antimicrobial compounds. A recent work carried out by our research group concerned the synergistic antibacterial activities of commercially available and chemically characterized Cinnamomum verum L. essential oil (C. verum EO) in association with sertraline, a selective serotonin reuptake inhibitor whose repositioning as a non-antibiotic drug has been explored over the years with encouraging results. The aim of this work was to explore the synergistic effects of C. verum EO with sertraline on both planktonic and sessile Candida species cells. Susceptibility testing and testing of the synergism of sertraline and C. verum EO against planktonic and sessile cells were performed using a broth microdilution assay and checkerboard methods. A synergistic effect was evident in both the planktonic cells and mature biofilms, with significant reductions in fungal viability. Indeed, the fractional inhibitory concentration index (FICI) was lower than 0.5 for all the associations, thus indicating significant synergism of the associations with the Candida strains examined. Moreover, the concentrations of sertraline able to inhibit Candida spp. strain growth and biofilm formation significantly decreased when it was used in combination with C. verum EO for all the strains considered, with a reduction percentage in the amount of each associated component ranging from 87.5% to 97%.