Genotypic and phenotypic characterisation of a nosocomial outbreak of Candida auris in Spain during 5 years.

OBJECTIVES: The investigation of Candida auris outbreaks is needed to provide insights into its population structure and transmission dynamics. We genotypically and phenotypically characterised a C. auris nosocomial outbreak occurred in Consorcio Hospital General Universitario de Valencia (CHGUV), Spain. METHODS: Data and isolates were collected from CHGUV from September 2017 (first case) until September 2021. Thirty-five isolates, including one from an environmental source, were randomly selected for whole genome sequencing (WGS), and the genomes were analysed along with a database with 335 publicly available genomes, assigning them to one of the five major clades. In order to identify polymorphisms associated with drug resistance, we used the fully susceptible GCA_003014415.1 strain as reference sequence. Known mutations in genes ERG11 and FKS1 conferring resistance to fluconazole and echinocandins, respectively, were investigated. Isolates were classified into aggregating or non-aggregating. RESULTS: All isolates belonged to clade III and were from an outbreak with a single origin. They clustered close to three publicly available genomes from a hospital from where the first patient was transferred, being the probable origin. The mutation VF125AL in the ERG11 gene, conferring resistance to fluconazole, was present in all the isolates and one isolate also carried the mutation S639Y in the FKS1 gene. All the isolates had a non-aggregating phenotype (potentially more virulent). CONCLUSIONS: Isolates are genotypically related and phenotypically identical but one with resistance to echinocandins, which seems to indicate that they all belong to an outbreak originated from a single isolate, remaining largely invariable over the years. This result stresses the importance of implementing infection control practices as soon as the first case is detected or when a patient is transferred from a setting with known cases.

Insights from Three Pan-European Multicentre Studies on Invasive Candida Infections and Outlook to ECMM Candida IV.

Invasive candidiasis and candidemia remain a significant public health concern. The European Confederation of Medical Mycology (ECMM) conducted three pan-European multicentre studies from 1997 to 2022 to investigate various aspects of invasive Candida infections. These studies revealed shifting trends in Candida species distribution, with an increase of non-albicans Candida species as causative pathogens, increasing rates of antifungal resistance, and persistently high mortality rates. Despite advancements in antifungal treatment, the persistently high mortality rate and increasing drug resistance, as well as limited drug access in low-income countries, underscore the need for continued research and development in the treatment of Candida infections. This review aims to summarize the findings of the three completed ECMM Candida studies and emphasize the importance of continued research efforts. Additionally, it introduces the upcoming ECMM Candida IV study, which will focus on assessing candidemia caused by non-albicans Candida species, including Candida auris, investigating antifungal resistance and tolerance, and evaluating novel treatment modalities on a global scale.

Emerging trends in pediatric candidemia: mapping the rise in Candida parapsilosis incidence and antifungal resistance in Turkey.

Candidemia is emerging as a significant concern in children, particularly among those with underlying conditions like malignancies or prematurity. The interpretation of epidemiological data on candidemias and their antifungal resistance plays a vital role in aiding diagnosis and guiding clinicians in treatment decisions. From 2014 to 2021, a retrospective analysis was conducted in Istanbul, Turkey; comparing Candida albicans and non-albicans (NAC) spp in both surviving and deceased groups. Furthermore, an examination of Candida parapsilosis and other species was performed, assessing various clinical and laboratory parameters. Among 93 patients, with a median age of 17 months, C. parapsilosis emerged as the predominant isolated species (44%), followed by C. albicans (34.4%). Resistance to fluconazole, voricanozole, and echinocandins, along with a history of broad-spectrum antibiotic use were found to be significantly higher in the non-albicans Candida group compared to C. albicans group. In the C. parapsilosis group, statistically lower age was identified in comparison to the other groups (P = .018). In addition, high fluconazole and voriconazole resistance was detected in Candida parapsilosis spp. Our study highlights a notable prevalence of C. parapsilosis, particularly in younger children, which is different from similar studies in childhood. This trend may be attributed to the common use of total parenteral nutrition and central venous catheter in gastrointestinal disorders and metabolic diseases. Furthermore, as anticipated, high azole resistance is noted in C. parapsilosis and other non-albicans Candida species. Interestingly, resistance to both amphotericin B and echinocandins within this group has been notably high. It is crucial to emphasize the considerable antifungal resistance seen in C. parapsilosis isolates.

The Impact of Cyclodextrins on the Physiology of Candida boidinii: Exploring New Opportunities in the Cyclodextrin Application.

Cyclodextrins, commonly used as excipients in antifungal formulations to improve the physicochemical properties and availability of the host molecules, have not been systematically studied for their effects and bioactivity without a complex active substance. This paper evaluates the effects of various cyclodextrins on the physiology of the test organism Candida boidinii. The research examines their impact on yeast growth, viability, biofilm formation and morphological changes. Native ACD, BCD, randomly methylated α- and ß-CD and quaternary ammonium α-CD and ß-CD were investigated in the 0.5-12.5 mM concentration range in both static and dynamic systems. The study revealed that certain cyclodextrins exhibited notable antifungal effects (up to ~69%) in dynamic systems; however, the biofilm formation was enhanced in static systems. The magnitude of these effects was influenced by several variables, including the size of the internal cavity, the concentration and structure of the cyclodextrins, and the contact time. Furthermore, the study found that CDs exhibited distinct effects in both static and dynamic systems, potentially related to their tendency to form aggregates. The findings suggest that cyclodextrins may have the potential to act as antifungal agents or growth promoters, depending on their structure and surrounding environments.

Efficacy of Curcumin-Mediated Antimicrobial Photodynamic Therapy on Candida spp.-A Systematic Review.

Oral candidiasis is a common problem among immunocompetent patients. The frequent resistance of Candida strains to popular antimycotics makes it necessary to look for alternative methods of treatment. The authors conducted a systematic review following the PRISMA 2020 guidelines. The objective of this review was to determine if curcumin-mediated blue light could be considered as an alternative treatment for oral candidiasis. PubMed, Google Scholar, and Cochrane Library databases were searched using a combination of the following keywords: (Candida OR candidiasis oral OR candidiasis oral OR denture stomatitis) AND (curcumin OR photodynamic therapy OR apt OR photodynamic antimicrobial chemotherapy OR PACT OR photodynamic inactivation OR PDI). The review included in vitro laboratory studies with Candida spp., in vivo animal studies, and randomized control trials (RCTs) involving patients with oral candidiasis or prosthetic stomatitis, published only in English. The method of elimination of Candida species in the studies was curcumin-mediated aPDT. A total of 757 studies were identified. Following the analysis of the titles and abstracts of the studies, only 42 studies were selected for in-depth screening, after which 26 were included in this study. All studies evaluated the antifungal efficacy of curcumin-mediated aPDT against C. albicans and non-albicans Candida. In studies conducted with planktonic cells solutions, seven studies demonstrated complete elimination of Candida spp. cells. The remaining studies demonstrated only partial elimination. In all cases, experiments on single-species yeast biofilms demonstrated partial, statistically significant inhibition of cell growth and reduction in biofilm mass. In vivo, curcumin-mediated aPDT has shown good antifungal activity against oral candidiasis also in an animal model. However, its clinical efficacy as a potent therapeutic strategy for oral candidiasis requires few further RCTs.

Hybrid Organic-Inorganic Copper and Cobalt Complexes for Antimicrobial Potential Applications.

BACKGROUND/AIMS: The naturally occurring phenolic chemical curcumin (CUR), which was derived from the Curcuma longa plant, has a variety of biological actions, including anti-inflammatory, antimicrobial, antioxidant, and anticancer activities. Curcumin is known for its restricted bioavailability due to its hydrophobicity, poor intestinal absorption, and quick metabolism. To boost the biological effects of these bioactive molecules, it is necessary to raise both their bioavailability and their solubility in water. Aim: The aim of this study is to synthesize and characterize hybrid organic-inorganic complexes of copper and cobalt, and to evaluate their antimicrobial potential against a range of pathogenic microorganisms. METHODS: The synthesis of metal curcumin complexes (Cu-CUR and Co-CUR) was achieved by mixing curcumin with copper acetate monohydrate. The solid residue was isolated, filtered, and dried in an oven. X-ray diffraction analysis was used to identify the structure and phase of the prepared samples. FTIR spectra were recorded using a Shimadzu 2200 module. The antimicrobial activity of the prepared complexes was evaluated against four bacterial strains and two Candida species. The chemical materials were dissolved in DMSO to a final concentration of 20%, and the plates were incubated at 37°C for 24 hours. The results showed that the prepared complexes had antimicrobial activity against the tested microorganisms. RESULTS: The study compared the Powder X-ray diffraction (XRD) patterns of prepared copper and cobalt complexes to pure curcumin, revealing new, isostructural complexes. The FTIR analysis showed that the Cu-CUR and Co-CUR complexes varied in their inhibitory effect against microorganisms, with Co-CUR being more effective. The results are consistent with previous studies showing the cobalt-curcumin complex was effective against various bacterial genera, with inhibition activity varying depending on the species and strains of microorganisms. CONCLUSION: Copper and cobalt curcumin complexes, synthesized at room temperature, exhibit high crystallinity and antimicrobial activity. Co-CUR, with its superior antibacterial potential, outperforms pure curcumin in inhibiting microbes. Further investigation is needed to understand their interaction mechanisms with bacteria and fungi.

Mechanism of action and synergistic effect of Eugenia uniflora extract in Candida spp.

The limited arsenal of antifungal drugs have prompted the search for novel molecules with biological activity. This study aimed to characterize the antifungal mechanism of action of Eugenia uniflora extract and its synergistic activity with commercially available antifungal drugs on the following Candida species: C. albicans, C. tropicalis, C. glabrata, C. parapsilosis and C. dubliniensis. In silico analysis was performed to predict antifungal activity of the major compounds present in the extract. Minimal inhibitory concentrations (MICs) were determined in the presence of exogenous ergosterol and sorbitol. Yeast cells were grown in the presence of stressors. The loss of membrane integrity was assessed using propidium iodide staining (fluorescence emission). Synergism between the extract and antifungal compounds (in addition to time kill-curves) was determined. Molecular docking revealed possible interactions between myricitrin and acid gallic and enzymes involved in ergosterol and cell wall biosynthesis. Candida cells grown in the presence of the extract with addition of exogenous ergosterol and sorbitol showed 2 to 8-fold increased MICs. Strains treated with the extract revealed greater loss of membrane integrity when compared to their Fluconazole counterparts, but this effect was less pronounced than the membrane damage caused by Amphotericin B. The extract also made the strains more susceptible to Congo red and Calcofluor white. A synergistic action of the extract with Fluconazole and Micafungin was observed. The E. uniflora extract may be a viable option for the treatment of Candida infections.

Therapy of traditional Chinese medicine in Candida spp. and Candida associated infections: A comprehensive review.

Candida spp. are commonly a group of opportunistic dimorphic fungi, frequently causing diverse fungal infections in immunocompromised or immunosuppressant patients from mucosal disturbs (oropharyngeal candidiasis and vulvovaginal candidiasis) to disseminated infections (systemic candidiasis) with high morbidity and mortality. Importantly, several Candida species can be isolated from diseased individuals with digestive, neuropathic, respiratory, metabolic and autoimmune diseases. Due to increased resistance to conventional antifungal agents, the arsenal for antifungal purpose is in urgent need. Traditional Chinese Medicines (TCMs) are a huge treasury that can be used as promising candidates for antimycotic applications. In this review, we make a short survey of microbiological (morphology and virulence) and pathological (candidiasis and Candida related infections) features of and host immune response (innate and adaptive immunity) to Candida spp.. Based on the chemical structures and well-studied antifungal mechanisms, the monomers, extracts, decoctions, essential oils and other preparations of TCMs that are reported to have fair antifungal activities or immunomodulatory effects for anticandidal purpose are comprehensively reviewed. We also emphasize the importance of combination and drug pair of TCMs as useful anticandidal strategies, as well as network pharmacology and molecular docking as beneficial complements to current experimental approaches. This review construct a therapeutic module that can be helpful to guide in-future experimental and preclinical studies in the combat against fungal threats aroused by C. albicans and non-albicans Candida species.

Comparative pharmacodynamics and dose optimization of liposomal amphotericin B against Candida species in an in vitro pharmacokinetic/pharmacodynamic model.

As comparative pharmacokinetic/pharmacodynamic (PK/PD) studies of liposomal amphotericin B (L-AMB) against Candida spp. are lacking, we explored L-AMB pharmacodynamics against different Candida species in an in vitro PK/PD dilution model. Eight Candida glabrata, Candida parapsilosis, and Candida krusei isolates (EUCAST/CLSI AMB MIC 0.125-1 mg/L) were studied in the in vitro PK/PD model simulating L-AMB Cmax = 0.25-64 mg/L and t1/2 = 9 h. The model was validated with one susceptible and one resistant Candida albicans isolate. The Cmax/MIC-log10CFU/mL reduction from the initial inoculum was analyzed with the Emax model, and Monte Carlo analysis was performed for the standard (3 mg/kg with Cmax = 21.87 ± 12.47 mg/L) and higher (5 mg/kg with Cmax = 83 ± 35.2 mg/L) L-AMB dose. A ≥1.5 log10CFU/mL reduction was found at L-AMB Cmax = 8 mg/L against C. albicans, C. parapsilosis, and C. krusei isolates (MIC 0.25-0.5 mg/L) whereas L-AMB Cmax ≥ 32 mg/L was required for C. glabrata isolates. The in vitro PK/PD relationship followed a sigmoidal pattern (R2 ≥ 0.85) with a mean Cmax/MIC required for stasis of 2.1 for C. albicans (close to the in vivo stasis), 24/17 (EUCAST/CLSI) for C. glabrata, 8 for C. parapsilosis, and 10 for C. krusei. The probability of target attainment was ≥99% for C. albicans wild-type (WT) isolates with 3 mg/kg and for wild-type isolates of the other species with 5 mg/kg. L-AMB was four- to eightfold less active against the included non-C. albicans species than C. albicans. A standard 3-mg/kg dose is pharmacodynamically sufficient for C. albicans whereas our data suggest that 5 mg/kg may be recommendable for the included non-C. albicans species.

Increase in candidemia cases and emergence of fluconazole-resistant Candida parapsilosis and C. auris isolates in a tertiary care academic hospital during the COVID-19 pandemic, Greece, 2020 to 2023.

BackgroundThe COVID-19 pandemic and the emergence of Candida auris have changed the epidemiological landscape of candidaemia worldwide.AimWe compared the epidemiological trends of candidaemia in a Greek tertiary academic hospital before (2009-2018) and during the early COVID-19 (2020-2021) and late COVID-19/early post-pandemic (2022-2023) era.MethodsIncidence rates, species distribution, antifungal susceptibility profile and antifungal consumption were recorded, and one-way ANOVA or Fisher's exact test performed. Species were identified by MALDI-ToF MS, and in vitro susceptibility determined with CLSI M27-Ed4 for C. auris and the EUCAST-E.DEF 7.3.2 for other Candida spp.ResultsIn total, 370 candidaemia episodes were recorded during the COVID-19 pandemic. Infection incidence (2.0 episodes/10,000 hospital bed days before, 3.9 during the early and 5.1 during the late COVID-19 era, p < 0.0001), C. auris (0%, 9% and 33%, p < 0.0001) and fluconazole-resistant C. parapsilosis species complex (SC) (20%, 24% and 33%, p = 0.06) infections increased over time, with the latter not associated with increase in fluconazole/voriconazole consumption. A significant increase over time was observed in fluconazole-resistant isolates regardless of species (8%, 17% and 41%, p < 0.0001). Resistance to amphotericin B or echinocandins was not recorded, with the exception of a single pan-echinocandin-resistant C. auris strain.ConclusionCandidaemia incidence nearly tripled during the COVID-19 era, with C. auris among the major causative agents and increasing fluconazole resistance in C. parapsilosis SC. Almost half of Candida isolates were fluconazole-resistant, underscoring the need for increased awareness and strict implementation of infection control measures.

Identification and antifungal susceptibility profile of uncommon yeast species at Fattouma Bourguiba University Hospital in Tunisia.

Despite the severe impact of uncommon yeast fungal infections and the pressing need for more research on the topic, there are still few studies available on the identification, epidemiology, and susceptibility profile of those pathogens. The aims of the current study were to define the profile of uncommon yeast species at Fattouma Bourguiba University Hospital using phenotypic, molecular, and proteomic methods and to study their antifungal susceptibility profile. Pre-identified uncommon yeast species were collected from 2018 to 2021. These isolates were further identified using phenotypic methods (ID32C® system and Vitek2® YST), matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS), and sequencing. The antifungal susceptibility profile was studied using the reference CLSI broth microdilution method. In total, 30 strains were collected during the study period. Referring to the sequencing, the most isolated uncommon species were Saprochaete capitata, Candida lusitaniae, Candida kefyr, Candida inconspicua, and Candida guilliermondii. A total of 90% of isolates were correctly identified by MALDI-TOF MS compared to 76.7% and 63.3% by ID32® C and VITEK® 2 YST, respectively. The isolated species showed variable responses to antifungals. Candida guilliermondii showed increased azole minimum inhibitory concentrations. Misidentification of uncommon yeast species was common using commercial phenotypic methods. The high percentage of concordance of MALDI-TOF results with sequencing highlights its high performance and usefulness as a routine diagnosis tool.

There is still little information on the epidemiology of uncommon emergent yeasts, although their implication in severe diseases and mainly invasive infections. Thus, the importance of an accurate identification and antifungal susceptibility testing for a better monitoring of related infections.

Surface-Charge Tuned Polymeric Nanoemulsions for Carvacrol Delivery in Interkingdom Biofilms.

Biofilms, intricate microbial communities entrenched in extracellular polymeric substance (EPS) matrices, pose formidable challenges in infectious disease treatment, especially in the context of interkingdom biofilms prevalent in the oral environment. This study investigates the potential of carvacrol-loaded biodegradable nanoemulsions (NEs) with systematically varied surface charges─cationic guanidinium (GMT-NE) and anionic carboxylate (CMT-NE). Zeta potentials of +25 mV (GMT-NE) and -33 mV (CMT-NE) underscore successful nanoemulsion fabrication (∼250 nm). Fluorescent labeling and dynamic tracking across three dimensions expose GMT-NE's superior diffusion into oral biofilms, yielding a robust antimicrobial effect with 99.99% killing for both streptococcal and Candida species and marked reductions in bacterial cell viability compared to CMT-NE (∼4-log reduction). Oral mucosa tissue cultures affirm the biocompatibility of both NEs with no morphological or structural changes, showcasing their potential for combating intractable biofilm infections in oral environment. This study advances our understanding of NE surface charges and their interactions within interkingdom biofilms, providing insights crucial for addressing complex infections involving bacteria and fungi in the demanding oral context.

Mechanism of azole resistance in Candida vulturna, an emerging multidrug resistant pathogen related with Candida haeumulonii and Candida auris.

BACKGROUND: Candida vulturna is an emerging pathogen belonging to the Metshnikowiaceae family together with Candida auris and Candida haemulonii species complex. Some strains of this species were reported to be resistant to several antifungal agents. OBJECTIVES: This study aims to address identification difficulties, evaluate antiungal susceptibilities and explore the molecular mechanisms of azole resistance of Candida vulturna. METHODS: We studied five C. vulturna clinical strains isolated in three Colombian cities. Identification was performed by phenotypical, proteomic and molecular methods. Antifungal susceptibility testing was performed following CLSI protocol. Its ERG11 genes were sequenced and a substitution was encountered in azole resistant isolates. To confirm the role of this substitution in the resistance phenotype, Saccharomyces cerevisiae strains with a chimeric ERG11 gene were created. RESULTS: Discrepancies in identification methods are highlighted. Sequencing confirmed the identification as C. vulturna. Antifungal susceptibility varied among strains, with four strains exhibiting reduced susceptibility to azoles and amphotericin B. ERG11 sequencing showed a point mutation (producing a P135S substitution) that was associated with the azole-resistant phenotype. CONCLUSIONS: This study contributes to the understanding of C. vulturna's identification challenges, its susceptibility patterns, and sheds light on its molecular mechanisms of azole resistance.

In vitro analysis of postbiotic antimicrobial activity against Candida Species in a minimal synthetic model simulating the gut mycobiota in obesity.

Gut fungal imbalances, particularly increased Candida spp., are linked to obesity. This study explored the potential of Lactiplantibacillus plantarum cell-free extracts (postbiotics) to modulate the growth of Candida albicans and Candida kefyr, key members of the gut mycobiota. A minimal synthetic gut model was employed to evaluate the effects of Lactiplantibacillus plantarum postbiotics on fungal growth in mono- and mixed cultures. Microreactors were employed for culturing, fungal growth was quantified using CFU counting, and regression analysis was used to evaluate the effects of postbiotics on fungal growth. Postbiotics at a concentration of 12.5% significantly reduced the growth of both Candida species. At 24 h, both C. albicans and C. kefyr in monocultures exhibited a decrease in growth of 0.11 log CFU/mL. In contrast, mixed cultures showed a more pronounced antifungal effect, with C. albicans and C. kefyr reductions of 0.62 log CFU/mL and 0.64 log CFU/mL, respectively. Regression analysis using the Gompertz model supported the antifungal activity of postbiotics and revealed species-specific differences in growth parameters. These findings suggest that L. plantarum postbiotics have the potential to modulate the gut mycobiota by reducing Candida growth, potentially offering a therapeutic approach for combating fungal overgrowth associated with obesity.

Structural and Functional Characterization of New Lipid Transfer Proteins with Chitin-Binding Properties: Insights from Protein Structure Prediction, Molecular Docking, and Antifungal Activity.

Faced with the emergence of multiresistant microorganisms that affect human health, microbial agents have become a serious global threat, affecting human health and plant crops. Antimicrobial peptides have attracted significant attention in research for the development of new microbial control agents. This work's goal was the structural characterization and analysis of antifungal activity of chitin-binding peptides from Capsicum baccatum and Capsicum frutescens seeds on the growth of Candida and Fusarium species. Proteins were initially submitted to extraction in phosphate buffer pH 5.4 and subjected to chitin column chromatography. Posteriorly, two fractions were obtained for each species, Cb-F1 and Cf-F1 and Cb-F2 and Cf-F2, respectively. The Cb-F1 (C. baccatum) and Cf-F1 (C. frutescens) fractions did not bind to the chitin column. The electrophoresis results obtained after chromatography showed two major protein bands between 3.4 and 14.2 kDa for Cb-F2. For Cf-F2, three major bands were identified between 6.5 and 14.2 kDa. One band from each species was subjected to mass spectrometry, and both bands showed similarity to nonspecific lipid transfer protein. Candida albicans and Candida tropicalis had their growth inhibited by Cb-F2. Cf-F2 inhibited the development of C. albicans but did not inhibit the growth of C. tropicalis. Both fractions were unable to inhibit the growth of Fusarium species. The toxicity of the fractions was tested in vivo on Galleria mellonella larvae, and both showed a low toxicity rate at high concentrations. As a result, the fractions have enormous promise for the creation of novel antifungal compounds.

Mangiferin potentiates the activity of antifungal agents against fluconazole-resistant Candida spp.

Aim: To evaluate the antifungal activity of mangiferin against Candida spp. resistant to fluconazole.Materials & methods: The antifungal activity of mangiferin was assessed using broth microdilution and its interaction with azoles and amphotericin B was evaluated by checkerboard. The activity of mangiferin against Candida spp. biofilms was assessed using the MTT colorimetric assay and its possible mechanism of action was evaluated using flow cytometry.Results: Mangiferin showed activity against Candida albicans, Candida tropicalis and Candida parapsilosis resistant to fluconazole and showed synergism with azoles and amphotericin B. Mangiferin increased the activity of antifungals against Candida biofilms and caused depolarization of the mitochondrial membrane and externalization of phosphatidylserine, suggesting apoptosis.Conclusion: mangiferin combined with antifungals has potential against Candida spp.

Candida is a type of fungus that can make people ill. Over time, many species of Candida have found ways to resist the drugs used to kill them. It is important to find new drugs. We decided to see if a substance called mangiferin works against Candida. We found that mangiferin works against Candida and may help other drugs to work better. We still need to do more studies to find out whether mangiferin can help prevent diseases caused by Candida in the future.

Anticandidal Activity of Various Probiotic Lactobacillus Strains and Their Efficacy Enhanced by Prebiotic Supplementation.

Probiotics and prebiotics have been considered as alternative approaches for promoting health. This study aimed to investigate the anticandidal potential of various probiotic Lactobacillus strains and their cell-free supernatants (CFSs). The study assessed the impact of inulin and some fruits as prebiotics on the growth of selected probiotic strains in relation to their anticandidal activity, production of short-chain fatty acids, total phenolic content, and antioxidant activity. Results revealed variations in anticandidal activity based on the specific strains and forms of probiotics used. Non-adjusted CFSs were the most effective against Candida strains, followed by probiotic cells and adjusted CFSs (pH 7). Lacticaseibacillus rhamnosus SD4, L. rhamnosus SD11 and L. rhamnosus GG displayed the strongest anticandidal activity. Non-adjusted CFSs from L. rhamnosus SD11, L. rhamnosus SD4 and L. paracasei SD1 exhibited notable anticandidal effects. The adjusted CFSs of L. rhamnosus SD11 showed the highest anticandidal activity against all non-albicans Candida (NAC) strains, whereas the others were ineffective. Supplementation of L. rhamnosus SD11 with prebiotics, particularly 2% (w/v) mangosteen, exhibited positive results in promoting probiotic growth, short-chain fatty acids production, total phenolic contents, and antioxidant activity, and the subsequent enhancing anticandidal activity against both C. albicans and NAC strains compared to conditions without prebiotics. In conclusion, both live cells and CFSs of tested strains, particularly L. rhamnosus SD11, exhibited the best anticandidal activity. Prebiotics supplementation, especially mangosteen, enhanced probiotic growth and beneficial metabolites against Candida growth. These finding suggested that probiotics and prebiotic supplementation may be an effective alternative treatment for Candida infections.

Candida spp. isolated from recreational coastal waters of Rio de Janeiro - Brazil: Focus on antifungal resistance and virulence attributes.

The use of recreational waters is a widespread activity worldwide, and one of the risks associated with this practice is the exposure of bathers to microorganisms that may arise due to pollution caused by inadequate infrastructure and sanitation. In the present work, we isolated Candida spp. (n = 24) from five recreational beaches in Rio de Janeiro, Brazil, in order to evaluate their susceptibility to antifungals, the production of virulence attributes and the in vivo virulence using Tenebrio molitor larvae as a model. The ITS1-5.8S-ITS2 gene sequencing identified thirteen isolates (54.1 %) as C. tropicalis, seven (29.1 %) as C. krusei (Pichia kudriavzevii), one (4.2 %) as C. rugosa (Diutina rugosa), one (4.2 %) as C. mesorugosa (Diutina mesorugosa), one (4.2 %) as C. utilis (Cyberlindnera jadinii) and one (4.2 %) as C. parapsilosis. C. tropicalis isolates showed resistance to azoles and susceptibility to amphotericin B, flucytosine and caspofungin. C. krusei isolates were resistant to fluconazole, caspofungin and itraconazole, with 42.8 % resistance to flucytosine, besides susceptibility to voriconazole and amphotericin B. The remaining species were susceptible to all tested antifungals. All Candida isolates adhered to abiotic surfaces and formed biofilm on polystyrene, albeit to varying degrees, and produced aspartic protease and hemolytic activity, which are considered fungal virulence attributes. C. tropicalis, C. krusei and C. utilis isolates produced phytase, while the only esterase producer was C. tropicalis. Regarding resistance to osmotic stress, all isolates of C. tropicalis, C. parapsilosis and C. mesorugosa grew up to 7.5 % NaCl; the remaining isolates grew up to 1.87-3.75 % NaCl. The mortality caused by fungal challenges in T. molitor larvae was variable, with C. tropicalis, C. utilis and C. parapsilosis being more virulent than C. krusei and C. rugosa complex. Collectively, the presence of these yeasts, particularly the virulent and resistant isolates, in recreational waters can pose a significant health risk to bathers.

Propensity of Candida spp. prosthetic joint infection clinical isolates to form aggregates in synovial fluid and the clinical ramifications.

BACKGROUND: Bacterial aggregation has been shown to occur in synovial fluid which are resistant to high concentrations of antibiotics. Yet the propensity of Candida spp. to form aggregates is unknown. OBJECTIVE: To assess the ability of numerous Candida spp. to form synovial fluid aggregates and the clinical ramifications of the aggregates. METHODS: Nine different Candidal prosthetic joint infection clinical isolates were evaluated for their ability to form aggregates at static and dynamic conditions and their resistance to high concentrations of amphotericin. Furthermore, the ability of tissue plasminogen activator (TPA) to disrupt the aggregates and enhance amphotericin activity was assessed. RESULTS: The results show that all species of Candida spp. evaluated formed aggregates in synovial fluid under dynamic conditions that were resistant to amphotericin. Yet no aggregates formed in tryptic soy broth under any conditions or in synovial fluid under static conditions. As well, when TPA was combined with amphotericin there was a statistically significant decrease (p < .005) in the amount of colony forming units per mL for all Candidal species evaluated. Interestingly, for Candida krusei there was no colony forming units observed after exposure to TPA and amphotericin. CONCLUSION: Our findings suggest that Candidal species form synovial fluid aggregates that are resistant to high dose amphotericin similar to those that occur with bacteria. However, the varying ability of the different Candida spp. to form hyphae and pseudohyphae compared to yeast cells may have direct impacts on the hardiness of the aggregates and thereby have clinical ramifications with respect to treatment durations.

Synthesis and Biological Evaluation of New Compounds with Nitroimidazole Moiety.

Heterocyclic compounds, particularly those containing azole rings, have shown extensive biological activity, including anticancer, antibacterial, and antifungal properties. Among these, the imidazole ring stands out due to its diverse therapeutic potential. In the presented study, we designed and synthesized a series of imidazole derivatives to identify compounds with high biological potential. We focused on two groups: thiosemicarbazide derivatives and hydrazone derivatives. We synthesized these compounds using conventional methods and confirmed their structures via nuclear magnetic resonance spectroscopy (NMR), MS, and elemental analysis, and then assessed their antibacterial and antifungal activities in vitro using the broth microdilution method against Gram-positive and Gram-negative bacteria, as well as Candida spp. strains. Our results showed that thiosemicarbazide derivatives exhibited varied activity against Gram-positive bacteria, with MIC values ranging from 31.25 to 1000 µg/mL. The hydrazone derivatives, however, did not display significant antibacterial activity. These findings suggest that structural modifications can significantly influence the antimicrobial efficacy of imidazole derivatives, highlighting the potential of thiosemicarbazide derivatives as promising candidates for further development in antibacterial therapies. Additionally, the cytotoxic activity against four cancer cell lines was evaluated. Two derivatives of hydrazide-hydrazone showed moderate anticancer activity.