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2.
Int J Food Microbiol ; 341: 109048, 2021 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-33486390

RESUMO

Yeasts are the leading cause of spoilage in yogurt. Considering the high demand from consumers to use natural products as an alternative to additives, essential oils (EOs) could be a promising solution to guarantee high microbiological standards. The present study highlighted the in vitro antifungal potential of cinnamon, ginger, lemongrass, mandarin, orange, lemon and lime EOs against spoilage yeasts isolated from yogurts prepared with pasteurized buffalo milk. A total of 74 isolates represented by 14 different species of Candida, Rhodotorula, Debaryomyces, Kluyveromyces and Yarrowia genera were subjected to a disc diffusion assay, showing lemongrass EO to have the highest antifungal activity (40.97 ± 9.86 mm), followed by cinnamon (38.46 ± 6.59 mm) and orange (12.00 ± 4.52 mm) EOs. Yarrowia lipolytica was less susceptible to lemongrass EO than Candida sake and Yarrowia deformans isolates. Ginger EO exhibited the lowest efficacy. A minimum inhibitory concentration (MIC) assay showed the ability of lemongrass and cinnamon EOs to inhibit the growth of all selected isolates at concentrations between ≤0.31 and 1.25 µL/mL. Therefore, for the first time, the two best-performing EOs (lemongrass and cinnamon) based on in vitro assays were assessed for their potential roles as preservatives in an in vivo yogurt model prepared at the laboratory scale. Since some limitations, such as the inhibition of lactic acid bacteria by cinnamon EO, consequently leading to fermentation failure as well as species-specific antifungal activity of lemongrass EO, were observed, further studies are needed to explore the possibility of using a slightly higher concentration of lemongrass EO and/or combinations of different EOs and/or their components. Finally, since yogurt spoilage could also be prevented by correct sanitation procedures of the production environment, the sanitizers commonly used in the food industry were tested against all isolates, showing the high efficiency of alcohol-based sanitizers and the ineffectiveness of chlorine-based sanitizers.


Assuntos
Antifúngicos/farmacologia , Cinnamomum zeylanicum/química , Cymbopogon/química , Óleos Voláteis/farmacologia , Leveduras/crescimento & desenvolvimento , Iogurte/microbiologia , Candida/efeitos dos fármacos , Candida/crescimento & desenvolvimento , Candida/isolamento & purificação , Citrus sinensis/química , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Contaminação de Alimentos/análise , Saccharomycetales/efeitos dos fármacos , Saccharomycetales/crescimento & desenvolvimento , Saccharomycetales/isolamento & purificação , Leveduras/efeitos dos fármacos , Leveduras/metabolismo
3.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 40(7): 1049-1055, 2020 May 25.
Artigo em Chinês | MEDLINE | ID: mdl-32701244

RESUMO

OBJECTIVE: To investigate the characteristics of growth and metabolism and the in vivo toxicity of Candida auris under different conditions. METHODS: We observed the growth of Candida auris and Candida albicans under routine culture conditions and in different pH and salt concentrations, and compared their activities of sugar fermentation using microbiochemical reaction tubes. Four-week-old nude mice were randomized into Candida auris infection group (n=5), Candida albicans infection group (n=5) and control group (n=5) for intragastric administration of 0.3 mL suspension the two Candida species (5×109 cfu/mL) or 0.3 mL normal saline. Samples of the liver, kidney, intestine, feces and blood were taken for analysis of the in vivo distribution and toxicity of Candida albicans by fungal culture and histopathological examination. RESULTS: Candida auris exhibited logarithmic growth at 8-24 h after inoculation and showed stable growth after 24 h. Candida auris showed optimal growth within the pH value range of 5-7 with a growth pattern identical to that of Candida albicans. Candida auris grew better than Candida albicans in media containing 5% and 10% NaCl, and could ferment glucose, sucrose, trehalose and sorbitol. Candida auris could be isolated from the feces, blood, liver and kidney of infected nude mice, and the liver had the highest fungal load (5.7 log10 cfu/g). Candida auris could cause pathological changes in the liver and intestine of the mice, but with a lesser severity as compared with Candida albicans. CONCLUSIONS: Candida auris exhibits optimal growth in mildly acidic or neutral conditions with a high salt tolerance, and can potentially penetrate the intestinal barrier into blood and lead to tissue injuries in hosts with immunosuppression.


Assuntos
Candida , Candidíase , Animais , Candida/crescimento & desenvolvimento , Candida/isolamento & purificação , Candida albicans/crescimento & desenvolvimento , Candidíase/microbiologia , Meios de Cultura , Camundongos , Camundongos Nus , Distribuição Aleatória
4.
Chemosphere ; 260: 127514, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32688309

RESUMO

The main aim of this study was to evaluate the performance of an air membrane bioreactor (aMBR) for the treatment of gas-phase methanol. A laboratory-scale hollow fiber aMBR was operated for 150 days, at inlet methanol concentrations varying between 2 and 30 g m-3 and at empty bed residence times (EBRT) of 30, 10 and 5 s. Under steady-state conditions, a maximum methanol removal efficiency (RE) of 98% was obtained at an EBRT of 30 s and a decrease in RE of methanol was observed at lower EBRTs. On increasing the inlet loading rate, some portion of gas-phase MeOH was stripped into the liquid phase due to its solubility in water. Under transient conditions, the MeOH removal efficiency dropped from an average value of 95%-90% after 5 h of 10-fold shock load and dropped from an average value of 95%-88% under 5-fold increase in shock load. During transient-state tests, the aMBR performed well under different upset loading conditions and a drop in RE of ∼ 5-10% was observed. However, the aMBR performance was restored within 1-2 days when pre-shock conditions were restored. The results from microbial structure analysis revealed a big shift of the dominant methanol degrader, from Candida boidinii strain TBRC 217 to Xanthobacter sp. and Fusicolla sp., respectively.


Assuntos
Poluentes Atmosféricos/análise , Reatores Biológicos/microbiologia , Membranas Artificiais , Metanol/análise , Biodegradação Ambiental , Biofilmes/crescimento & desenvolvimento , Candida/crescimento & desenvolvimento , Desenho de Equipamento , Filtração/métodos , Xanthobacter/crescimento & desenvolvimento
5.
Int J Infect Dis ; 98: 227-229, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32592907

RESUMO

Sodium-glucose co-transporter 2 (SGLT2) inhibitors exhibit impressive cardio-renal benefits in patients with a high cardiovascular risk. Genital yeast infections are important side effects of this class of drugs. We report a case of Candida glabrata sepsis secondary to a Candida infection of the urostomy of a patient on SGLT2 inhibitor therapy. In urostomy patients, one should critically evaluate the risk of mycotic infections against the cardiovascular and glycaemic benefits of SGLT2 inhibition. Urostomy patients without a high cardiovascular risk should not be treated with SGLT2 inhibitors.


Assuntos
Hipoglicemiantes/efeitos adversos , Sepse/etiologia , Inibidores do Transportador 2 de Sódio-Glicose/efeitos adversos , Idoso , Candida/efeitos dos fármacos , Candida/crescimento & desenvolvimento , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Humanos , Hipoglicemiantes/uso terapêutico , Masculino , Sepse/microbiologia , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Urina/microbiologia
8.
J Sci Food Agric ; 100(6): 2782-2790, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32020610

RESUMO

BACKGROUND: Soy sauce is a well-known condiment worldwide. However, the high salt content in soy sauce contributes to the high intake of sodium salt, which usually results in high blood pressure. High salt soy sauce usually has the better quality (aroma and taste) than low salt. Tetragenococcus halophilus and Candida versatilis are important starters for soy sauce fermentation. It is of urgent need to explore what the effect of these two strains on the aroma- and taste-attributes of soy sauce to achieve high quality fermentation with low salt. RESULTS: In this study, aroma-active and taste compounds in soy sauce were reviewed and listed. Then, soy sauce fermentation inoculated with different combinations of T. halophilus (at different inoculated time) and C. versatilis were completed. Aroma-active and taste compounds in different samples were quantified. Multivariate analysis was used to analyze these data. The aroma-active compounds which were highly related to the inoculation of T. halophilus and C. versatilis were found. Meanwhile, the addition time of T. halophilus could also be highly related to the production of aroma-active compounds. More importantly, T. halophilus was highly correlated with the production of umami-taste compounds in soy sauce, including aspartic acid, glutamic acid, alanine and N -succinyl-glutamic acid. CONCLUSION: These results will provide a better understanding of the effects of T. halophilus and C. versatilis on the formation of significant aroma-active and umami-taste constituents in soy sauce. Furthermore, it will be helpful to realize fermentative control of soy sauce with high quality at low salt. © 2020 Society of Chemical Industry.


Assuntos
Candida/crescimento & desenvolvimento , Enterococcaceae/crescimento & desenvolvimento , Fermentação , Alimentos de Soja/análise , Condimentos/análise , Tecnologia de Alimentos/métodos , Odorantes/análise , Paladar
9.
Sci Rep ; 10(1): 3011, 2020 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-32080302

RESUMO

Chlorella vulgaris, like a wide range of other microalgae, are able to grow mixotrophically. This maximizes its growth and production of polysaccharides (PS). The extracted polysaccharides have a complex monosaccharide composition (fructose, maltose, lactose and glucose), sulphate (210.65 ± 10.5 mg g-1 PS), uronic acids (171.97 ± 5.7 mg g-1 PS), total protein content (32.99 ± 2.1 mg g-1 PS), and total carbohydrate (495.44 ± 8.4 mg g-1 PS). Fourier Transform infrared spectroscopy (FT-IR) analysis of the extracted polysaccharides showed the presence of N-H, O-H, C-H, -CH3, >CH2, COO-1, S=O and the C=O functional groups. UV-Visible spectral analysis shows the presence of proteins, nucleic acids and chemical groups (ester, carbonyl, carboxyl and amine). Purified polysaccharides were light green in color and in a form of odorless powder. It was soluble in water but insoluble in other organic solvents. Thermogravimetric analysis demonstrates that Chlorella vulgaris soluble polysaccharide is thermostable until 240°C and degradation occurs in three distinct phases. Differential scanning calorimetry (DSC) analysis showed the characteristic exothermic transition of Chlorella vulgaris soluble polysaccharides with crystallization temperature peaks at 144.1°C, 162.3°C and 227.7°C. The X-ray diffractogram illustrated the semicrystalline nature of these polysaccharides. Silver nanoparticles (AgNPs) had been biosynthesized using a solution of Chlorella vulgaris soluble polysaccharides. The pale green color solution of soluble polysaccharides was turned brown when it was incubated for 24 hours with 100 mM silver nitrate in the dark, it showed peak maximum located at 430 nm. FT-IR analysis for the biosynthesized AgNPs reported the presence of carbonyl, -CH3, >CH2, C-H,-OH and -NH functional groups. Scanning and transmission electron microscopy show that AgNPs have spherical shape with an average particle size of 5.76. Energy-dispersive X-ray (EDX) analysis showed the dominance of silver. The biosynthesized silver nanoparticles were tested for its antimicrobial activity and have positive effects against Bacillus sp., Erwinia sp., Candida sp. Priming seeds of Triticum vulgare and Phaseolus vulgaris with polysaccharides solutions (3 and 5 mg mL-1) resulted in significant enhancement of seedling growth. Increased root length, leaf area, shoot length, photosynthetic pigments, protein content, carbohydrate content, fresh and dry biomass were observed, in addition these growth increments may be attributed to the increase of antioxidant activities.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/farmacologia , Chlorella vulgaris/química , Reguladores de Crescimento de Planta/farmacologia , Polissacarídeos/farmacologia , Prata/farmacologia , Antibacterianos/isolamento & purificação , Antioxidantes/isolamento & purificação , Bacillus/efeitos dos fármacos , Bacillus/crescimento & desenvolvimento , Candida/efeitos dos fármacos , Candida/crescimento & desenvolvimento , Chlorella vulgaris/crescimento & desenvolvimento , Chlorella vulgaris/metabolismo , Erwinia/efeitos dos fármacos , Erwinia/crescimento & desenvolvimento , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Extratos Vegetais/química , Reguladores de Crescimento de Planta/isolamento & purificação , Polissacarídeos/isolamento & purificação , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Sementes/efeitos dos fármacos , Sementes/crescimento & desenvolvimento , Prata/química , Triticum/efeitos dos fármacos , Triticum/crescimento & desenvolvimento
10.
J Appl Microbiol ; 128(2): 426-437, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31621139

RESUMO

AIM: The aim of this present study was to investigate the antifungal mechanism of sertraline against Candida auris (C. auris) and its effect on biofilm formation. METHODS AND RESULTS: Sertraline, a repurposing drug with a history of human use for the treatment of depression was screened against three different isolates of C. auris, and was found to possess efficient antifungal activity. The antifungal activity of sertraline was further confirmed by killing kinetics assay and post-antifungal effect (PAFE). Sertraline inhibited C. auris yeast to hyphae conversion and further the inhibition of biofilm formation showed 71% inhibition upon treatment. Cell damage caused due to C. auris after treatment with sertraline was observed using SEM and cell membrane damage was ascertained using flow cytometry by Propidium Iodide (PI) uptake assay. The results of sorbitol protection assay and ergosterol effect assay suggested that sertraline did not affect the cell wall and did not act by binding to membrane ergosterol. The mechanism of action of sertraline against C. auris was understood through in silico docking studies that revealed the binding nature of sertraline to the sterol 14 alpha demethylase which is involved in ergosterol biosynthesis. Ergosterol that was quantified from treated cells showed a 5·5-fold decrease in ergosterol production. CONCLUSION: Sertraline displayed promising antifungal activity against C. auris involved in candidiasis infection and the mechanism of action was predicted. SIGNIFICANCE AND IMPACT OF THIS STUDY: The results of this study can encourage for the development of new antifungal agents and can be promising antifungal agent against C. auris infection.


Assuntos
Antifúngicos/farmacologia , Biofilmes/efeitos dos fármacos , Candida/efeitos dos fármacos , Candidíase/microbiologia , Sertralina/farmacologia , Candida/crescimento & desenvolvimento , Candida/fisiologia , Ergosterol/metabolismo , Humanos , Testes de Sensibilidade Microbiana
11.
J Ethnopharmacol ; 248: 112352, 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-31676401

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Warburgia ugandensis Sprague subspecies ugandensis is a plant widely distributed in Eastern, Central and Southern Africa. In humans, it is used to treat respiratory infections, tooth aches, malaria, skin infections, venereal diseases, diarrhea, fevers and aches. AIM OF THE STUDY: This study aims to identify the bioactive compounds against clinically important biofilm-forming strains of Candida and staphylococci that are responsible for tissue and implanted device-related infections. METHODS: Using a bioassay-guided fractionation approach, hexane -, ethanol -, acetone - and water extracts from the leaves of W. ugandensis, their subsequent fractions and isolated compounds were tested against both developing and preformed 24 h-biofilms of Candida albicans SC5314, Candida glabrata BG2, Candida glabrata ATCC 2001, Staphylococcus epidermidis 1457 and Staphylococcus aureus USA 300 using microtiter susceptibility tests. Planktonic cells were also tested in parallel for comparison purposes. Confocal scanning laser microscopy was also used to visualize effects of isolated compounds on biofilm formation. RESULTS: Warburganal, polygodial and alpha-linolenic acid (ALA) were the major bioactive compounds isolated from the acetone extract of W. ugandensis. For both warburganal and polygodial, the biofilm inhibitory concentration that inhibits 50% of C. albicans developing biofilms (BIC50) was 4.5 ±â€¯1 and 10.8 ±â€¯5 µg/mL respectively. Against S. aureus developing biofilms, this value was 37.9 ±â€¯8 µg/mL and 25 µg/mL with warburganal and ALA respectively. Eradication of preformed 24 h biofilms was also observed. Interestingly, synergy between the sesquiterpenoids and azoles against developing C. albicans biofilms resulted in an approximately ten-fold decrease of the effective concentration required to completely inhibit growth of the biofilms by individual compounds. The hydroxyl group in position C-9 in warburganal was identified as essential for activity against staphylococcal biofilms. We also identified additional promising bioactive sesquiterpenoids; drimenol and drimendiol from the structure-activity relationship (SAR) studies. CONCLUSIONS: ALA and four sesquiterpenoids: polygodial, warburganal, drimenol and drimendiol, have shown biofilm-inhibitory activity that has not been reported before and is worth following up. These compounds are potential drug candidates to manage biofilm-based infections, possibly in combination with azoles.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Biofilmes/efeitos dos fármacos , Candida/efeitos dos fármacos , Magnoliopsida , Extratos Vegetais/farmacologia , Folhas de Planta , Staphylococcus/efeitos dos fármacos , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antifúngicos/química , Antifúngicos/isolamento & purificação , Biofilmes/crescimento & desenvolvimento , Candida/crescimento & desenvolvimento , Magnoliopsida/química , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Staphylococcus/crescimento & desenvolvimento , Relação Estrutura-Atividade
12.
Nat Prod Res ; 34(12): 1653-1662, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30422685

RESUMO

In this work we synthetized the bioinspired benzoxanthene lignans (BXLs) 3, 14-22, and the phenazine derivative 23 as potential antimycotic agents. MICs and MFCs against Candida strains were determined. In a preliminary screening, compounds 3, 15, 20, 21, 22 were substantially inactive. Compounds 14 and 17 showed antifungal activity, being able to inhibit the growth of the majority of Candida strains with MIC values in the range 4.6-19.2 µM (14) and 26.0-104.3 µM (17); for three strains, the MICs were lower than those obtained using the antimycotic drug fluconazole. The three BXLs 18, 19 and 23 showed some MIC values lower than that of fluconazole; 18 was also active against two non-albicans Candida strains resistant to fluconazole. Phenazine 23, although active only against one strain (MIC = 1.3 µM), was one order of magnitude more potent than fluconazole. All the BXLs were fungicidal.


Assuntos
Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Lignanas/síntese química , Antifúngicos/síntese química , Candida/crescimento & desenvolvimento , Fluconazol/farmacologia , Testes de Sensibilidade Microbiana , Xantenos
13.
Folia Microbiol (Praha) ; 65(2): 393-405, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31401762

RESUMO

Nosocomial infections are an important cause of morbi-mortality worldwide. The increase in the rate of resistance to conventional drugs in these microorganisms has stimulated the search for new therapeutic options. The nitro moiety (NO2) is an important pharmacophore of molecules with high anti-infective activity. We aimed to synthesize new nitro-derivates and to evaluate their antibacterial and anti-Candida potential in vitro. Five compounds [3-nitro-2-phenylchroman-4-ol (3); 3-nitro-2-phenyl-2H-chromene (4a); 3-nitro-2-(4-chlorophenyl)-2H-chromene (4b); 3-nitro-2-(4-fluorophenyl)-2H-chromene (4c), and 3-Nitro-2-(2,3-dichlorophenyl)-2H-chromene (4d)] were efficiently synthesized by Michael-aldol reaction of 2-hydroxybenzaldehyde with nitrostyrene, resulting in one ß-nitro-alcohol (3) and four nitro-olefins (4a-4d). The antibacterial and anti-Candida potentials were evaluated by assaying minimal inhibitory concentration (MIC), minimum fungicidal concentration (MFC), and minimum bactericidal concentration (MBC). Mono-halogenated nitro-compounds (4b and 4c) showed anti-staphylococcal activity with MIC values of 15.6-62.5 µg/mL and MBC of 62.5 µg/mL. However, the activity against Gram-negative strains was showed to be considerably lower and our data suggests that this effect was associated with the outer membrane. Furthermore, nitro-compounds 4c and 4d presented activity against Candida spp. with MIC values ranging from 7.8-31.25 µg/mL and MFC of 15.6-500 µg/mL. In addition, these compounds were able to induce damage in fungal cells increasing the release of intracellular material, which was associated with actions on the cell wall independent of quantitative changes in chitin and ß-glucan. Together, these findings show that nitro-compounds can be exploited as anti-staphylococcal and anti-Candida prototypes.


Assuntos
Anti-Infecciosos/farmacologia , Nitrocompostos/farmacologia , Anti-Infecciosos/síntese química , Anti-Infecciosos/química , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Candida/efeitos dos fármacos , Candida/crescimento & desenvolvimento , Infecção Hospitalar/tratamento farmacológico , Infecção Hospitalar/microbiologia , Desenho de Fármacos , Humanos , Testes de Sensibilidade Microbiana , Nitrocompostos/síntese química , Nitrocompostos/química
14.
Dis Mon ; 66(7): 100920, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31796204

RESUMO

BACKGROUND: Leprosy represents a chronic progressive debilitating disease. The severe morbidity associated with leprosy predisposes the patients to opportunistic infections. To assess the oral candida prevalence and species specificity in lepromatous leprosy patients. METHODS: The cross-sectional study included 70 lepromatous leprosy patients under a multi-drug regimen for less than 1 year (group 1) and 70 healthy volunteers (group 2). Both group 1 and 2 were matched for potential confounding factors including age, gender, ethnicity, absence of HIV co-infection. Oral swab samples obtained from both groups were subjected to a series of conventional and molecular diagnostic modalities. RESULTS: Yeast growth was statistically higher (0.0006) in group 1 (45.7%) than in group 2 (18.5%). 28 of the 32 yeast growth in group 1 and all 13 yeast growth in group 2 were identified as candida. Among the 28 candida species in group 1, 23 (71.88%) were Candida albicans, 3 (9.37%) were Candida parapsilosis, 1 (3.13%) was Candida lusitaniae and 1 (3.13%) was Candida nivariensis. Among group 2, 11 (84.6%) were Candida albicans, 1 (7.7%) was Candida parapsilosis and 1 was Candida tropicalis. CONCLUSION: Oral candida prevalence is higher in leprosy patients than in healthy individuals, indicating a predisposition towards opportunistic infections. The increasing prevalence of the non-candida albicans species in leprosy is a major concern as they have shown to possess inherent resistant towards common anti-fungal agents.


Assuntos
Candida/crescimento & desenvolvimento , Candidíase Bucal/epidemiologia , Hanseníase/tratamento farmacológico , Infecções Oportunistas/epidemiologia , Adulto , Candida/genética , Candida/ultraestrutura , Candida albicans/genética , Candida albicans/crescimento & desenvolvimento , Candida albicans/ultraestrutura , Candida parapsilosis/genética , Candida parapsilosis/crescimento & desenvolvimento , Candida parapsilosis/ultraestrutura , Candida tropicalis/genética , Candida tropicalis/crescimento & desenvolvimento , Candida tropicalis/ultraestrutura , Estudos de Casos e Controles , Estudos Transversais , Feminino , Humanos , Índia/epidemiologia , Hanseníase/complicações , Hanseníase/microbiologia , Hanseníase/patologia , Masculino , Pessoa de Meia-Idade , Prevalência , Especificidade da Espécie
15.
Microbiol Res ; 230: 126330, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31541842

RESUMO

Glycoconjugates found on cell walls of Candida species are fundamental for their pathogenicity. Laborious techniques have been employed to investigate the sugar composition of these microorganisms. Herein, we prepared a nanotool, based on the fluorescence of quantum dots (QDs) combined with the specificity of Cramoll lectin, to evaluate glucose/mannose profiles on three Candida species. The QDs-Cramoll conjugates presented specificity and bright fluorescence emission. The lectin preserved its biological activity after the conjugation process mediated by adsorption interactions. The labeling of Candida species was analyzed by fluorescence microscopy and quantified by flow cytometry. Morphological analyses of yeasts labeled with QDs-Cramoll conjugates indicated that C. glabrata (2.7 µm) was smaller when compared to C. albicans (4.0 µm) and C. parapsilosis sensu stricto (3.8 µm). Also, C. parapsilosis population was heterogeneous, presenting rod-shaped blastoconidia. More than 90% of cells of the three species were labeled by conjugates. Inhibition and saturation assays indicated that C. parapsilosis had a higher content of exposed glucose/mannose than the other two species. Therefore, QDs-Cramoll conjugates demonstrated to be effective fluorescent nanoprobes for evaluation of glucose/mannose constitution on the cell walls of fungal species frequently involved in candidiasis.


Assuntos
Candida/química , Corantes Fluorescentes/química , Glucose/análise , Lectinas/química , Manose/análise , Microscopia de Fluorescência/métodos , Candida/crescimento & desenvolvimento , Candida/isolamento & purificação , Candida/metabolismo , Candidíase/diagnóstico , Candidíase/microbiologia , Parede Celular/química , Parede Celular/metabolismo , Glucose/metabolismo , Humanos , Manose/metabolismo , Microscopia de Fluorescência/instrumentação , Nanopartículas/química , Pontos Quânticos/química
16.
J Appl Microbiol ; 128(1): 88-101, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31509623

RESUMO

AIMS: Staphylococcus aureus (a bacterial pathogen) and Candida sp. (opportunistic fungi) are two clinically relevant biofilm-forming microbes responsible for a majority of community- and nosocomial-acquired infections. Dual species biofilm formation between S. aureus and Candida sp. extremely enhances the antimicrobial resistance of the micro-organisms and is difficult to treat with antibiotic therapy. Hence, it is crucial to explore new antimicrobial agents. Auranofin (AF) is a mixed ligand gold compound and has recently been repurposed as an antibacterial and antifungal agent. However, the effects of AF against dual species biofilm have remained largely untested. METHODS AND RESULTS: In the present study, by constructing biofilms on microplates and urinary catheter surfaces, AF showed strong planktonic cells and biofilm inhibitory effects against mono- and dual culture models of S. aureus and Candida albicans but only exhibited moderate antibiofilm effects on Candida parapsilosis. Auranofin could be synergistic with subminimal inhibitory concentrations of amphotericin B against S. aureus + C. albicans/C. parapsilosis dual biofilms. Auranofin also showed effective antimicrobial effects on vancomycin-resistant strains. However, the antimicrobial effects of AF were decreased in the presence of heat-inactivated foetal bovine serum. CONCLUSIONS: In summary, AF could effectively inhibit S. aureus and C. albicans mono- and dual biofilm formation in vitro. SIGNIFICANCE AND IMPACT OF THE STUDY: Coexistence between Staphylococcus aureus and Candida sp. in dual biofilms leads to increased resistance to some conventionally used antimicrobials, indicating a need for alternative treatments. This study demonstrates the potential for the Au-containing compound AF in the treatment of dual biofilm infections and encourages further investigation of this treatment for clinical use.


Assuntos
Anti-Infecciosos/farmacologia , Auranofina/farmacologia , Biofilmes/efeitos dos fármacos , Candida/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Anfotericina B/farmacologia , Biofilmes/crescimento & desenvolvimento , Candida/crescimento & desenvolvimento , Técnicas de Cocultura , Sinergismo Farmacológico , Testes de Sensibilidade Microbiana , Especificidade da Espécie , Staphylococcus aureus/crescimento & desenvolvimento , Cateteres Urinários/microbiologia
17.
PLoS One ; 14(12): e0218360, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31887112

RESUMO

Microbial ingredients such as Candida utilis yeast are known to be functional protein sources with immunomodulating effects whereas soybean meal causes soybean meal-induced enteritis in the distal intestine of Atlantic salmon (Salmo salar L.). Inflammatory or immunomodulatory stimuli at the local level in the intestine may alter the plasma proteome profile of Atlantic salmon. These deviations can be helpful indicators for fish health and, therefore potential tools in the diagnosis of fish diseases. The present work aimed to identify local intestinal tissue responses and changes in plasma protein profiles of Atlantic salmon fed inactive dry Candida utilis yeast biomass, soybean meal, or combination of soybean meal based diet with various inclusion levels of Candida utilis. A fishmeal based diet was used as control diet. Inclusion of Candida utilis yeast to a fishmeal based diet did not alter the morphology, immune cell population or gene expression of the distal intestine. Lower levels of Candida utilis combined with soybean meal modulated immune cell populations in the distal intestine and reduced the severity of soybean meal-induced enteritis, while higher inclusion levels of Candida utilis were less effective. Changes in the plasma proteomic profile revealed differences between the diets but did not indicate any specific proteins that could be a marker for health or disease. The results suggest that Candida utilis does not alter intestinal morphology or induce major changes in plasma proteome, and thus could be a high-quality alternative protein source with potential functional properties in diets for Atlantic salmon.


Assuntos
Ração Animal/microbiologia , Candida/crescimento & desenvolvimento , Salmo salar/crescimento & desenvolvimento , Ração Animal/análise , Criação de Animais Domésticos/métodos , Animais , Aquicultura/métodos , Dieta , Expressão Gênica , Intestinos/fisiologia , Proteínas , Proteoma/metabolismo , Proteômica , Soja
18.
Biofouling ; 35(9): 997-1006, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31710252

RESUMO

Surface pre-reacted glass-ionomer (S-PRG) is a bioactive filler produced by PRG technology, which is applied to various dental materials. The inhibitory effects of S-PRG eluate against Candida, the most common fungal oral pathogen, were investigated. Minimum inhibitory concentrations (MIC) and anti-biofilm activities were tested against Candida albicans, Candida glabrata, Candida krusei, and Candida tropicalis. For the in vivo study, Galleria mellonella was used as a model to evaluate the effects of S-PRG on toxicity, hemocyte counts and candidiasis. The MIC of S-PRG ranged from 5 to 40% (v/v). S-PRG eluate exhibited anti-biofilm activity for all the Candida species tested. Furthermore, injection of S-PRG eluate into G. mellonella was not toxic to the larvae and protected G. mellonella against experimental candidiasis. In addition, S-PRG eluate inhibited biofilm formation by C. albicans, C. glabrata, C. krusei, and C. tropicalis and exerted protective effects on G. mellonella against experimental candidiasis in vivo.


Assuntos
Antifúngicos/farmacologia , Biofilmes/efeitos dos fármacos , Candida/efeitos dos fármacos , Candidíase Bucal/prevenção & controle , Cimentos de Ionômeros de Vidro/farmacologia , Mariposas/efeitos dos fármacos , Resinas Acrílicas/farmacologia , Animais , Antifúngicos/toxicidade , Biofilmes/crescimento & desenvolvimento , Candida/crescimento & desenvolvimento , Cimentos de Ionômeros de Vidro/toxicidade , Larva/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Mariposas/microbiologia , Dióxido de Silício/farmacologia
19.
Medicine (Baltimore) ; 98(44): e17704, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31689800

RESUMO

For early diagnosis and treatment of invasive candidiasis (IC), the well-known risk factors may not apply in the intensive care unit (ICU). This retrospective study identified the risk factors predicting IC and candidemia in cancer patients under intensive care after gastrointestinal surgery.Enrolled were 229 cancer patients admitted to our oncology surgical ICU after gastrointestinal surgery between January 1, 2010 and October 31, 2014.The most common types of solid gastrointestinal cancers were gastric (49.8%), colon (20.1%), and esophageal (18.3%). The percentage of patients with corrected Candida colonization index (CCI) ≥0.4 was 31.9%. IC was confirmed in 19 patients (8.3%), and the ICU mortality was 15.8%. Candida albicans accounted for 52.6% of the total number of pathogenic Candida isolates. Among patients with CCI ≥0.4, the cancers with the highest prevalence were cardiac (45%) and gastric (36%), with ICU mortalities of 20% and 4.9%, respectively. For the diagnosis of candidemia, (1-3)-ß-D-glucan (BDG) ≥80 pg/mL showed a sensitivity and specificity of 25% and 82.7%, respectively, positive and negative predictive values 6.7% and 95.7%, and area under the receiver operating characteristic curve 0.512. CCI ≥0.4 was the only significant predictor of IC, and number of organ failures was the only predictor of candidemia (P = .000 and .026).CCI ≥0.4 was the only significant risk factor predicting IC, with greater prediction of intra-abdominal candidiasis but failure to predict candidemia. Blood culture and BDG detection are recommended to supplement diagnosis. Patients may have multifocal and high-grade Candida colonization after cardiac surgery, and; therefore, are at high risk of IC, which should be taken seriously.


Assuntos
Candidemia/epidemiologia , Candidíase Invasiva/epidemiologia , Neoplasias Gastrointestinais/epidemiologia , Neoplasias Gastrointestinais/cirurgia , APACHE , Fatores Etários , Idoso , Candida/crescimento & desenvolvimento , Estado Terminal , Feminino , Hospitais Universitários , Humanos , Unidades de Terapia Intensiva , Tempo de Internação , Masculino , Técnicas Microbiológicas , Pessoa de Meia-Idade , Escores de Disfunção Orgânica , Estudos Retrospectivos , Fatores de Risco , Sepse/epidemiologia
20.
Mycopathologia ; 184(6): 775-786, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31679132

RESUMO

Candida can adhere and form biofilm on biomaterials commonly used in medical devices which is a key attribute that enhances its ability to cause infections in humans. Furthermore, biomaterial-related infections represent a major therapeutic challenge since Candida biofilms are implicated in antifungal therapies failure. The goals of the present work were to investigate the effect of three 5-aminoimidazole-4-carbohydrazonamides, namely (Z)-5-amino-1-methyl-N'-aryl-1H-imidazole-4-carbohydrazonamides [aryl = phenyl (1a), 4-fluorophenyl (1b), 3-fluorophenyl (1c)], on Candida albicans and Candida krusei biofilm on nanohydroxyapatite substrate, a well-known bioactive ceramic material. To address these goals, both quantitative methods (by cultivable cell numbers) and qualitative evaluation (by scanning electron microscopy) were used. Compounds cytocompatibility towards osteoblast-like cells was also evaluated after 24 h of exposure, through resazurin assay. The three tested compounds displayed a strong inhibitory effect on biofilm development of both Candida species as potent in vitro activity against C. albicans sessile cells. Regarding cytocompatibility, a concentration-dependent effect was observed. Together, these findings indicated that the potent activity of imidazole derivatives on Candida spp. biofilms on nanohydroxyapatite substrate, in particular compound 1c, is worth further investigating.


Assuntos
Antifúngicos/farmacologia , Biofilmes/efeitos dos fármacos , Candida , Próteses e Implantes/microbiologia , Infecções Relacionadas à Prótese/tratamento farmacológico , Materiais Biocompatíveis , Biofilmes/crescimento & desenvolvimento , Candida/efeitos dos fármacos , Candida/crescimento & desenvolvimento , Candida albicans/efeitos dos fármacos , Candida albicans/crescimento & desenvolvimento , Linhagem Celular/efeitos dos fármacos , Humanos , Imidazóis/farmacologia , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , Osteoblastos/efeitos dos fármacos , Infecções Relacionadas à Prótese/microbiologia
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