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1.
Pest Manag Sci ; 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39092877

RESUMO

BACKGROUND: Growing concerns about sustainability have driven the search for eco-friendly pest management solutions. Combining natural and synthetic compounds within controlled release systems is a promising strategy. This study investigated the co-encapsulation of the natural compound citral (Cit) and the synthetic antifungal cyproconazole (CPZ) using two water-based nanocarriers: solid lipid nanoparticles (SLNs) and chitosan nanoparticles (CSNPs). RESULTS: Both CSNPs and SLNs loaded with Cit + CPZ displayed superior antifungal activity against Botrytis cinerea compared to free compounds. Notably, CSNPs with a 2:1 Cit:CPZ ratio exhibited the highest efficacy, achieving a minimum inhibitory concentration (MIC100) of < 1.56 µg mL-1, lower than the 12.5 µg mL-1 of non-encapsulated compounds. This formulation significantly reduced the required synthetic CPZ while maintaining efficacy, highlighting its potential for environmentally friendly pest control. CONCLUSION: The successful co-encapsulation of Cit + CPZ within CSNPs, particularly at a 2:1 ratio, demonstrates a promising approach for developing effective and sustainable antifungal formulations against B. cinerea. © 2024 Society of Chemical Industry.

2.
Chem Biodivers ; : e202400945, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39106337

RESUMO

Chalcone (E)-1,3-diphenyl-prop-2-en-1-one and a series of 14 methoxylated derivatives have been synthesized via Claisen-Schmidt aldol condensation and characterized by FTIR, CG/MS/DIC, 1D (1H and 13C), 2D (COSY, HSQC, and HMBC) NMR, and EMAR techniques. All molecules were tested at 1 mM concentration for antifungal (Sclerotium sp., Macrophomina phaesolina and Colletotrichum gloeosporioides), antibacterial (Acidovorax citrulli two strains), and antiprotozoal (Phytomonas serpens) activities. Unmodified chalcone (CH0) and derivatives CH1, CH2, CH8 stood out in terms of antifungal activity. CH0 presented IC50 values of 47.3 µM (9.8 µg/mL) for the fungus C. gloeosporioides. In addition, fluorescence microscopy indicated that CH0 promoted loss of hyphal cell membrane integrity. The CH1 and CH2 derivatives promoted the inhibition of Sclerotium sp. with IC50 of 127.5 µM (32.9 µg/mL) and 110.4 µM (29.6 µg/mL), respectively. All molecules showed high activity against the phytoparasite P. serpens with IC50 values of 0.98, 2.40, 10.25, and 3.11 µM for the derivatives CH2, CH3, CH5 and CH14 respectively. The results demonstrated that derivatives methoxylated in both rings (CH2) as well as derivatives with a furan ring associated with the methoxy group in ring A, as well as unmodified chalcone can be promising agricultural fungicides for controlling the fungi studied.

4.
Braz J Microbiol ; 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39110398

RESUMO

Candida species resistant to fluconazole have raised concern in the scientific medical community due to high mortality in patients with invasive disease. In developing countries, such as Brazil, fluconazole is the most commonly used antifungal, and alternative treatments are expensive or not readily available. Furthermore, the occurrence of biofilms is common, coupled with their inherent resistance to antifungal therapies and the host's immune system, these microbial communities have contributed to making infections caused by these yeasts an enormous clinical challenge. Therefore, there is an urgent need to develop alternative medicines, which surpass the effectiveness of already used therapies, but which are also effective against biofilms. Therefore, the present study aimed to describe for the first time the antifungal and antibiofilm action of the derivative 2-amino-5,6,7,8-tetrahydro-4 H-cyclohepta[b]thiophene-3-isopropyl carboxylate (2AT) against clinical strains of Candida spp. resistant to fluconazole (FLZ). When determining the minimum inhibitory concentrations (MIC), it was found that the compound has antifungal action at concentrations of 100 to 200 µg/mL, resulting in 100% inhibition of yeast cells. Its synergistic effect with the drug FLZ was also observed. The antibiofilm action of the compound in subinhibitory concentrations was detected, alone and in association with FLZ. Moreover, using scanning electron microscopy, it was observed that the compound 2AT in isolation was capable of causing significant ultrastructural changes in Candida. Additionally, it was also demonstrated that the compound 2AT acts by inducing characteristics compatible with apoptosis in these yeasts, such as chromatin condensation, when visualized by transmission electron microscopy, indicating the possible mechanism of action of this molecule. Furthermore, the compound did not exhibit toxicity in J774 macrophage cells up to a concentration of 4000 µg/mL. In this study, we identify the 2AT derivative as a future alternative for invasive candidiasis therapy, in addition, we highlighted the promise of a strategy combined with fluconazole in combating Candida infections, especially in cases of resistant isolates.

5.
Foods ; 13(15)2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39123510

RESUMO

The organic acids produced by lactic acid bacteria (LAB) during the fermentation of sourdoughs have the ability to reduce the growth of different molds. However, this ability depends on the LAB used. For this reason, in this study, the proportions of different LAB were optimized to obtain aqueous extracts (AEs) from sourdough to reduce fungal growth in vitro, control the acetic acid concentration, and obtain a specific lactic to acetic acid ratio. In addition, the optimized mixtures were used to formulate partially baked bread (PBB) and evaluate the mold growth and bread quality during refrigerated storage. Using a simplex-lattice mixture design, various combinations of Lactiplantibacillus plantarum, Lacticaseibacillus casei, and Lactobacillus acidophilus were evaluated for their ability to produce organic acids and inhibit mold growth. The mixture containing only Lpb. plantarum significantly reduced the growth rates and extended the lag time of Penicillium chrysogenum and P. corylophilum compared with the control. The AEs' pH values ranged from 3.50 to 3.04. Organic acid analysis revealed that using Lpb. plantarum yielded higher acetic acid concentrations than when using mixed LAB. This suggests that LAB-specific interactions significantly influence organic acid production during fermentation. The reduced radial growth rates and extended lag times for both molds compared to the control confirmed the antifungal properties of the AEs from the sourdoughs. Statistical analyses of the mixture design using polynomial models demonstrated a good fit for the analyzed responses. Two optimized LAB mixtures were identified that maximized mold lag time, targeted the desired acetic acid concentration, and balanced the lactic to acetic acid ratio. The addition of sourdough with optimized LAB mixtures to PBB resulted in a longer shelf life (21 days) and adequately maintained product quality characteristics during storage. PBB was subjected to complete baking and sensory evaluation. The overall acceptability was slightly higher in the control without sourdough (7.50), followed by bread formulated with the optimized sourdoughs (ranging from 6.78 to 7.10), but the difference was not statistically significant (p > 0.05). The sensory analysis results indicated that the optimization was used to successfully formulate a sourdough bread with a sensory profile closely resembling that of a nonsupplemented one. The designed LAB mixtures can effectively enhance sourdough bread's antifungal properties and quality, providing a promising approach for extending bread shelf life while maintaining desirable sensory attributes.

6.
Mycoses ; 67(8): e13780, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39132817

RESUMO

BACKGROUND: Invasive fungal diseases (IFD) are high morbidity and mortality infections in children with cancer suffering episodes of high-risk febrile neutropenia (HRFN). IFD epidemiology has changed in the last two decades, with an increasing incidence in recent years due to the growing number of immunocompromised children at risk for IFD. The aim of this study was to evaluate the incidence of IFD in children with cancer in the period 2016-2020 compared to 2004-2006 in six hospitals in Chile. METHODS: Prospective, multicentre study, carried out between 2016 and 2020 in six hospitals in Chile. The defined cohort corresponds to a dynamic group of HRFN episodes in patients <18 years old with cancer, who at the fourth day of evolution still presented fever and neutropenia (persistent HRFN). Each episode was followed until resolution of FN. The incidence of IFD was calculated between 2016 and 2020 and compared with data obtained in the period 2004-2006. The incidence rate was estimated. RESULTS: A total of 777 episodes of HRFN were analysed; 257 (33.1%) were considered as persistent-HRFN occurring in 174 patients. The median age was 7 years (IQR: 3-12 years) and 52.3% (N = 91) were male. Fifty-three episodes of IFD were detected: 21 proven, 14 probable and 18 possible. Possible IFD were excluded, leaving 239 episodes of persistent-HRFN with an IFD incidence of 14.6% (95% CI 10.5-19.9) and an incidence rate of 13.6 IFD cases per 1000 days of neutropenia (95% CI 9.5-20.0). Compared to 2004-2006 cohort (incidence: 8.5% (95% CI 5.2-13.5)), a significant increase in incidence of 6.1% (95% CI 0.2-12.1, p = .047) was detected in cohorts between 2016 and 2020. CONCLUSION: We observed a significant increase in IFD in 2016-2020, compared to 2004-2006 period.


Assuntos
Infecções Fúngicas Invasivas , Neoplasias , Humanos , Chile/epidemiologia , Masculino , Estudos Prospectivos , Criança , Feminino , Pré-Escolar , Infecções Fúngicas Invasivas/epidemiologia , Infecções Fúngicas Invasivas/tratamento farmacológico , Neoplasias/epidemiologia , Neoplasias/complicações , Incidência , Hospedeiro Imunocomprometido , Adolescente , Lactente , Antineoplásicos/uso terapêutico
7.
Glycobiology ; 34(9)2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39088584

RESUMO

The limited availability of efficient treatments for Candida infections and the increased emergence of antifungal-resistant strains stimulates the search for new antifungal agents. We have previously isolated a sunflower mannose-binding lectin (Helja) with antifungal activity against Candida albicans, capable of binding mannose-bearing oligosaccharides exposed on the cell surface. This work aimed to investigate the biological and biophysical basis of Helja's binding to C. albicans cell wall mannans and its influence on the fungicidal activity of the lectin. We evaluated the interaction of Helja with the cell wall mannans extracted from the isogenic parental strain (WT) and a glycosylation-defective C. albicans with altered cell wall phosphomannosylation (mnn4∆ null mutants) and investigated its antifungal effect. Helja exhibited stronger antifungal activity on the mutant strain, showing greater inhibition of fungal growth, loss of cell viability, morphological alteration, and formation of clusters with agglutinated cells. This differential biological activity of Helja was correlated with the biophysical parameters determined by solid phase assays and isothermal titration calorimetry, which demonstrated that the lectin established stronger interactions with the cell wall mannans of the mnn4∆ null mutant than with the WT strain. In conclusion, our results provide new evidence on the nature of the Helja molecular interactions with cell wall components, i.e. phosphomannan, and its impact on the antifungal activity. This study highlights the relevance of plant lectins in the design of effective antifungal therapies.


Assuntos
Antifúngicos , Candida albicans , Parede Celular , Antifúngicos/farmacologia , Antifúngicos/química , Candida albicans/efeitos dos fármacos , Parede Celular/efeitos dos fármacos , Parede Celular/metabolismo , Lectinas de Plantas/química , Lectinas de Plantas/farmacologia , Helianthus/química , Mananas/química , Mananas/farmacologia , Mananas/metabolismo , Testes de Sensibilidade Microbiana
8.
Front Pharmacol ; 15: 1394053, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39101130

RESUMO

Introduction: Despite the rising concern with fungal resistance, a myriad of molecules has yet to be explored. Geraniol, linalool, and citronellal are monoterpenes with the same molecular formula (C10H18O), however, neither the effect of these compounds on inflammatory axis induced by Candida spp. nor the antibiofilm Structure-Activity Relationship (SAR) have been well-investigated. Herein we analyzed geraniol, linalool and citronellal antifungal activity, cytotoxicity, and distinctive antibiofilm SAR, also the influence of geraniol on Candida spp induced dysregulated inflammatory axis, and in vivo toxicity. Methods: Minimal inhibitory (MIC) and fungicidal (MFC) concentrations against Candida spp were defined, followed by antibiofilm activity (CFU-colony forming unit/mL/g of dry weight). Cytotoxic activity was assessed using human monocytes (THP-1) and oral squamous cell (TR146). Geraniol was selected for further analysis based on antifungal, antibiofilm and cytotoxic results. Geraniol was tested using a dual-chamber co-culture model with TR146 cells infected with C. albicans, and THP-1 cells, used to mimic oral epithelium upon fungal infection. Expression of Candida enzymes (phospholipase-PLB and aspartyl proteases-SAP) and host inflammatory cytokines (interleukins: IL-1ß, IL-6, IL-17, IL-18, IL-10, and Tumor necrosis factor-TNF) were analyzed. Lastly, geraniol in vivo toxicity was assessed using Galleria mellonella. Results: MIC values obtained were 1.25-5 mM/mL for geraniol, 25-100 mM/mL for linalool, and 100-200 mM/mL for citronellal. Geraniol 5 and 50 mM/mL reduced yeast viability during biofilm analysis, only 500 mM/mL of linalool was effective against a 72 h biofilm and no biofilm activity was seen for citronellal. LD50 for TR146 and THP-1 were, respectively: geraniol 5.883 and 8.027 mM/mL; linalool 1.432 and 1.709 mM/mL; and citronellal 0.3006 and 0.1825 mM/mL. Geraniol was able to downregulate expression of fungal enzymes and host pro-inflammatory cytokines IL-1ß, IL-6, and IL-18. Finally, safety in vivo parameters were observed up to 20 mM/Kg. Discussion: Despite chemical similarities, geraniol presented better antifungal, antibiofilm activity, and lower cytotoxicity when compared to the other monoterpenes. It also showed low in vivo toxicity and capacity to downregulate the expression of fungal enzymes and host pro-inflammatory cytokines. Thus, it can be highlighted as a viable option for oral candidiasis treatment.

9.
J Fungi (Basel) ; 10(7)2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-39057348

RESUMO

Invasive fungal disease causes high morbidity and mortality among immunocompromised patients. Resistance to conventional antifungal drugs and the toxicity associated with high doses highlight the need for effective antifungal therapies. In this study, the antifungal potential of the ethanolic extract of Anacardium occidentale (Cashew Leaf) leaves were evaluated against Candida albicans and C. auris. The antifungal activity was tested by the broth microdilution method and growth kinetic test. To further explore its antifungal action mode, spectrofluorophotometry, confocal microscopy and scanning and transmission electron microscopy were performed. Additionally, heterozygous knockout strains associated with resistance to oxidative stress were included in the study. We found that A. occidentale could inhibit the proliferation and growth of C. albicans at concentrations of 62.5 and 125 µg/mL. The doubling time was also drastically affected, going from 2.8 h to 22.5 h, which was also observed in C. auris. The extract induced the accumulation of intracellular reactive oxygen species (ROS), resulting in endoplasmic reticulum stress and mitochondrial dysfunction, while it did not show cytotoxicity or hemolytic activity at the concentrations evaluated. Our work preliminarily elucidated the potential mechanisms of A. occidentale against C. albicans on a cellular level, and might provide a promising option for the design of a new treatment for invasive candidiasis.

10.
Pharmaceuticals (Basel) ; 17(7)2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-39065720

RESUMO

The green synthesis of silver nanoparticles (AgNPs) can be developed using safe and environmentally friendly routes, can replace potentially toxic chemical methods, and can increase the scale of production. This study aimed to synthesize AgNPs from aqueous extracts of guarana (Paullinia cupana) leaves and flowers, collected in different seasons of the year, as a source of active biomolecules capable of reducing silver ions (Ag+) and promoting the stabilization of colloidal silver (Ag0). The plant aqueous extracts were characterized regarding their metabolic composition by liquid chromatography coupled to high-resolution mass spectrometry (UHPLC-HRMS/MS), phenolic compound content, and antioxidant potential against free radicals. The synthesized AgNPs were characterized by UV/Vis spectrophotometry, dynamic light scattering (DLS), nanoparticle tracking analysis (NTA), transmission electron microscopy (TEM), and scanning electron microscopy coupled to energy-dispersive X-ray spectrometry (EDX). The results demonstrated that the chemical characterization indicated the presence of secondary metabolites of many classes of compounds in the studied aqueous extracts studied, but alkaloids and flavonoids were predominant, which are widely recognized for their antioxidant capabilities. It was possible to notice subtle changes in the properties of the nanostructures depending on parameters such as seasonality and the part of the plant used, with the AgNPs showing surface plasmon resonance bands between 410 and 420 nm using the leaf extract and between 440 and 460 nm when prepared using the flower extract. Overall, the average hydrodynamic diameters of the AgNPs were similar among the samples (61.98 to 101.6 nm). Polydispersity index remained in the range of 0.2 to 0.4, indicating that colloidal stability did not change with storage time. Zeta potential was above -30 mV after one month of analysis, which is adequate for biological applications. TEM images showed AgNPs with diameters between 40.72 to 48.85 nm and particles of different morphologies. EDX indicated silver content by weight between 24.06 and 28.81%. The synthesized AgNPs exhibited antimicrobial efficacy against various pathogenic microorganisms of clinical and environmental interest, with MIC values between 2.12 and 21.25 µg/mL, which is close to those described for MBC values. Therefore, our results revealed the potential use of a native species of plant from Brazilian biodiversity combined with nanotechnology to produce antimicrobial agents.

11.
Int J Mol Sci ; 25(14)2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39063009

RESUMO

Candida albicans is one of the agents of invasive candidiasis, a life-threatening disease strongly associated with hospitalization, particularly among patients in intensive care units with central venous catheters. This study aimed to evaluate the synergistic activity of the antifungal peptide ToAP2 combined with fluconazole against C. albicans biofilms grown on various materials. We tested combinations of different concentrations of the peptide ToAP2 with fluconazole on C. albicans biofilms. These biofilms were generated on 96-well plates, intravenous catheters, and infusion tubes in RPMI medium at two maturation stages. Scanning electron microscopy and atomic force microscopy were employed to assess the biofilm structure. We also evaluated the expression of genes previously proven to be involved in C. albicans biofilm formation in planktonic and biofilm cells after treatment with the peptide ToAP2 using qPCR. ToAP2 demonstrated a synergistic effect with fluconazole at concentrations up to 25 µM during both the early and mature stages of biofilm formation in 96-well plates and on medical devices. Combinations of 50, 25, and 12.5 µM of ToAP2 with 52 µM of fluconazole significantly reduced the biofilm viability compared to individual treatments and untreated controls. These results were supported by substantial structural changes in the biofilms observed through both scanning and atomic force microscopy. The gene expression analysis of C. albicans cells treated with 25 µM of ToAP2 revealed a decrease in the expression of genes associated with membrane synthesis, along with an increase in the expression of genes involved in efflux pumps, adhesins, and filamentation. Our results highlight the efficacy of the combined ToAP2 and fluconazole treatment against C. albicans biofilms. This combination not only shows therapeutic potential but also suggests its utility in developing preventive biofilm tools for intravenous catheters.


Assuntos
Antifúngicos , Biofilmes , Candida albicans , Sinergismo Farmacológico , Fluconazol , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Fluconazol/farmacologia , Candida albicans/efeitos dos fármacos , Candida albicans/fisiologia , Antifúngicos/farmacologia , Peptídeos Antimicrobianos/farmacologia , Testes de Sensibilidade Microbiana , Humanos , Microscopia de Força Atômica , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo
12.
Int J Mol Sci ; 25(14)2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-39063186

RESUMO

The present study investigates the interactions between eight glucosinolate hydrolysis products (GHPs) sourced from broccoli by-products and the detoxifying enzymes of Botrytis cinerea, namely eburicol 14-alpha-demethylase (CYP51) and glutathione-S-transferase (GST), through in silico analysis. Additionally, in vitro assays were conducted to explore the impact of these compounds on fungal growth. Our findings reveal that GHPs exhibit greater efficacy in inhibiting conidia germination compared to mycelium growth. Furthermore, the results demonstrate the antifungal activity of glucosinolate hydrolysis products derived from various parts of the broccoli plant, including inflorescences, leaves, and stems, against B. cinerea. Importantly, the results suggest that these hydrolysis products interact with the detoxifying enzymes of the fungus, potentially contributing to their antifungal properties. Extracts rich in GHPs, particularly iberin and indole-GHPs, derived from broccoli by-products emerge as promising candidates for biofungicidal applications, offering a sustainable and novel approach to plant protection by harnessing bioactive compounds from agricultural residues.


Assuntos
Antifúngicos , Botrytis , Brassica , Glucosinolatos , Botrytis/efeitos dos fármacos , Glucosinolatos/química , Glucosinolatos/farmacologia , Glucosinolatos/metabolismo , Brassica/microbiologia , Hidrólise , Antifúngicos/farmacologia , Antifúngicos/química , Esporos Fúngicos/efeitos dos fármacos , Esporos Fúngicos/crescimento & desenvolvimento , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Simulação de Acoplamento Molecular , Testes de Sensibilidade Microbiana
14.
Sci Total Environ ; 947: 174662, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-38997029

RESUMO

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.


Assuntos
Antifúngicos , Candida , Farmacorresistência Fúngica , Brasil , Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Candida/patogenicidade , Candida/genética , Virulência , Testes de Sensibilidade Microbiana , Animais , Praias
15.
Future Microbiol ; : 1-11, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38979570

RESUMO

Aim: To develop a ß-AgVO3 gel and evaluate its physicochemical stability and antifungal activity against Candida albicans. Materials & methods: The gel was prepared from the minimum inhibitory concentration (MIC) of ß-AgVO3. The physicochemical stability was evaluated by centrifugation, accelerated stability (AS), storage (St), pH, syringability, viscosity and spreadability tests and antifungal activity by the agar diffusion. Results: The MIC was 62.5 µg/ml. After centrifugation, AS and St gels showed physicochemical stability. Lower viscosity and higher spreadability were observed for the higher ß-AgVO3 concentration and the minimum force for extrusion was similar for all groups. Antifungal effect was observed only for the ß-AgVO3 gel with 20xMIC. Conclusion: The ß-AgVO3 gel showed physicochemical stability and antifungal activity.


We used silver and vanadium to make a gel that can kill fungi in the mouth. We looked at the color of the gel, it's smell and also checked how well it lasted. The gel turned yellow and had no smell and did not spoil for at least 2 months. When we tested the gel against a type of fungus, it worked as well as another medicine called chlorhexidine, which is sold in pharmacies. But when we compared it with another medicine called nystatin, our gel was not as effective in killing the fungus.

16.
J Med Microbiol ; 73(7)2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38979984

RESUMO

Introduction. The development of new antifungal drugs has become a global priority, given the increasing cases of fungal diseases together with the rising resistance to available antifungal drugs. In this scenario, drug repositioning has emerged as an alternative for such development, with advantages such as reduced research time and costs.Gap statement. Propafenone is an antiarrhythmic drug whose antifungal activity is poorly described, being a good candidate for further study.Aim. This study aims to evaluate propafenone activity against different species of Candida spp. to evaluate its combination with standard antifungals, as well as its possible action mechanism.Methodology. To this end, we carried out tests against strains of Candida albicans, Candida auris, Candida parapsilosis, Candida tropicalis, Candida glabrata and Candida krusei based on the evaluation of the MIC, minimum fungicidal concentration and tolerance level, along with checkerboard and flow cytometry tests with clinical strains and cell structure analysis by scanning electron microscopy (SEM).Results. The results showed that propafenone has a 50% MIC ranging from 32 to 256 µg ml-1, with fungicidal activity and positive interactions with itraconazole in 83.3% of the strains evaluated. The effects of the treatments observed by SEM were extensive damage to the cell structure, while flow cytometry revealed the apoptotic potential of propafenone against Candida spp.Conclusion. Taken together, these results indicate that propafenone has the potential for repositioning as an antifungal drug.


Assuntos
Antifúngicos , Candida , Testes de Sensibilidade Microbiana , Propafenona , Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Candida/crescimento & desenvolvimento , Propafenona/farmacologia , Humanos , Itraconazol/farmacologia , Sinergismo Farmacológico , Farmacorresistência Fúngica/efeitos dos fármacos , Candidíase/microbiologia , Candidíase/tratamento farmacológico , Reposicionamento de Medicamentos
17.
Braz J Microbiol ; 2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39003363

RESUMO

The objective of the investigation was to improve phosphate solubilization in tomato plants by Bacillus licheniformis, a rhizobacterium that promotes plant growth. Ultraviolet (UV) radiation, Ethyl methanesulfonate (EMS) and Ethidium bromide (EtBr) mutagenesis produced twenty-one mutants. Phosphate solubilization was higher in the PM7 (physical mutant) (121.00 g mL-1) than in the wild type (82.00 g mL-1). PM7 showed high antifungal activity against Phytophthora capsici, Fusarium oxysporum and Dematophora necatrix besides increased siderophore production and HCN production. In a net-house experiment, PM7 improved root and shoot parameters, P assimilation and soil P availability in tomato plants. This study demonstrates the potential of PM7 as an effective rhizobacterium for enhancing nutrient availability and plant growth.

18.
Braz J Microbiol ; 55(3): 2557-2568, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38954219

RESUMO

Fusarium oxysporum is a cross-kingdom pathogen that infects humans, animals, and plants. The primary concern regarding this genus revolves around its resistance profile to multiple classes of antifungals, particularly azoles. However, the resistance mechanism employed by Fusarium spp. is not fully understood, thus necessitating further studies to enhance our understanding and to guide future research towards identifying new drug targets. Here, we employed an untargeted proteomic approach to assess the differentially expressed proteins in a soil isolate of Fusarium oxysporum URM7401 cultivated in the presence of amphotericin B and fluconazole. In response to antifungals, URM7401 activated diverse interconnected pathways, such as proteins involved in oxidative stress response, proteolysis, and lipid metabolism. Efflux proteins, antioxidative enzymes and M35 metallopeptidase were highly expressed under amphotericin B exposure. Antioxidant proteins acting on toxic lipids, along with proteins involved in lipid metabolism, were expressed during fluconazole exposure. In summary, this work describes the protein profile of a resistant Fusarium oxysporum soil isolate exposed to medical antifungals, paving the way for further targeted research and discovering new drug targets.


Assuntos
Anfotericina B , Antifúngicos , Fluconazol , Proteínas Fúngicas , Fusarium , Proteômica , Microbiologia do Solo , Fusarium/efeitos dos fármacos , Fusarium/metabolismo , Fusarium/genética , Antifúngicos/farmacologia , Antifúngicos/metabolismo , Fluconazol/farmacologia , Anfotericina B/farmacologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Farmacorresistência Fúngica , Testes de Sensibilidade Microbiana , Proteoma/análise
19.
Carbohydr Res ; 543: 109220, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39038396

RESUMO

Chitin is a polymer of N-acetylglucosamine and an essential component of the fungal cell wall. Chitosan is the deacetylated form of chitin and is also important for maintaining the integrity of this structure. Both polysaccharides are widely distributed in nature and have been shown to have a variety of applications in biomedicine, including their potential in immune sensing and as potential antifungal agents. In addition, chitin has been reported to play an important role in the pathogen-host interaction, involving innate and adaptive immune responses. This paper will explore the role of chitin and chitosan when incorporated into nanobiocomposites to improve their efficacy in detecting fungi of medical interest and inhibiting their growth. Potential applications in diagnostic and therapeutic medicine will be discussed, highlighting their promise in the development of more sensitive and effective tools for the early diagnosis of fungal infections. This review aims to highlight the importance of the convergence of nanotechnology and biology in addressing public health challenges.


Assuntos
Antifúngicos , Quitina , Quitosana , Fungos , Quitina/química , Quitina/farmacologia , Quitosana/química , Quitosana/farmacologia , Antifúngicos/farmacologia , Antifúngicos/química , Fungos/efeitos dos fármacos , Fungos/química , Humanos , Nanocompostos/química , Micoses/imunologia , Micoses/tratamento farmacológico , Micoses/diagnóstico
20.
Am J Infect Control ; 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39059713

RESUMO

BACKGROUND: Candida auris, an emerging multidrug-resistant yeast, has become a global concern due to its association with nosocomial outbreaks and resistance to antifungal medications. The COVID-19 pandemic has exacerbated the situation, with several outbreaks reported worldwide, including in Mexico. We describe the clinical and microbiological characteristics of a multicentric outbreak in private institutions in Mexico. METHODS: A retrospective observational study was conducted across 4 Christus Muguerza Hospital Health Care System facilities in Monterrey, Mexico, where simultaneous outbreaks of C auris occurred. Patients with colonization or infection with C auris between September 2020 and December 2023 were included. RESULTS: Analysis revealed 37 cases, predominantly male (median age, 55.8years). While most cases were initially colonization, a significant proportion progressed to infection (32.4%). Patients with documented infection had longer intensive care unit and hospital stays, often requiring mechanical ventilation. Antifungal treatment varied, with empirical fluconazole being the first drug in most cases, followed by anidulafungin and caspofungin. Resistance to fluconazole was widespread, but susceptibility to other antifungals varied. The overall mortality rates were high (40.5%), with no significant difference in median survival between colonized and infected patients. CONCLUSIONS: We reported a high rate of infection in previously colonized cases associated with longer hospital lenght stay, and a high susceptibility to echinocandins.

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