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1.
Braz J Microbiol ; 55(3): 2119-2130, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38954220

RESUMO

Biosurfactants, sustainable alternatives to petrochemical surfactants, are gaining attention for their potential in medical applications. This study focuses on producing, purifying, and characterizing a glycolipid biosurfactant from Candida sp. UFSJ7A, particularly for its application in biofilm prevention on siliconized latex catheter surfaces. The glycolipid was extracted and characterized, revealing a critical micellar concentration (CMC) of 0.98 mg/mL, indicating its efficiency at low concentrations. Its composition, confirmed through Fourier transform infrared spectroscopy (FT-IR) and thin layer chromatography (TLC), identified it as an anionic biosurfactant with a significant ionic charge of -14.8 mV. This anionic nature contributes to its biofilm prevention capabilities. The glycolipid showed a high emulsification index (E24) for toluene, gasoline, and soy oil and maintained stability under various pH and temperature conditions. Notably, its anti-adhesion activity against biofilms formed by Escherichia coli, Enterococcus faecalis, and Candida albicans was substantial. When siliconized latex catheter surfaces were preconditioned with 2 mg/mL of the glycolipid, biofilm formation was reduced by up to 97% for E. coli and C. albicans and 57% for E. faecalis. These results are particularly significant when compared to the efficacy of conventional surfactants like SDS, especially for E. coli and C. albicans. This study highlights glycolipids' potential as a biotechnological tool in reducing biofilm-associated infections on medical devices, demonstrating their promising applicability in healthcare settings.


Assuntos
Biofilmes , Candida , Catéteres , Glicolipídeos , Tensoativos , Glicolipídeos/farmacologia , Glicolipídeos/química , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Tensoativos/farmacologia , Tensoativos/química , Candida/efeitos dos fármacos , Candida/fisiologia , Catéteres/microbiologia , Látex/química , Látex/farmacologia , Escherichia coli/efeitos dos fármacos , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/fisiologia , Candida albicans/efeitos dos fármacos , Candida albicans/fisiologia
2.
J Fungi (Basel) ; 10(4)2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38667939

RESUMO

Candidemia is one of the healthcare-associated infections that has high mortality. The risk factors that predispose a patient to develop this infection are mostly found in patients of greater severity and COVID-19 contributes to the risk of death. The aim of this study is to evaluate epidemiological characteristics and risk factors for mortality in patients with candidemia before and during the COVID-19 pandemic era. This is a retrospective study conducted at Instituto Central from 2016 to 2020 of patients with candidemia that were evaluated for demographic data, medical history, risk factors, microbiological data, therapeutic measures, complementary exams, device management, and outcome defined by 30-day mortality. A total of 170 episodes were included (58.2% males; mean age of 56 years). The overall incidence density of candidemia per 1000 admissions and per 1000 patient-days was 1.17 and 0.17, respectively, with an increase of 38% in the year 2020. The use of a central venous catheter was the most prevalent (93.5%) condition, followed by the previous use of antibiotics (91.1%). Corticosteroid use ranked seventh (56.4%). C. albicans was responsible for 71 (41.7%) of the isolates, followed by C. tropicalis and C. glabrata, with 34 (20%) isolates each. Echinocandin was prescribed in 60.1% of cases and fluconazole in 37%. Echocardiography resulted in six (5.08%) cases of endocarditis and fundoscopy resulting in two (2.4%) endophthalmitis. The 30-day mortality was 93/170 (54.7%). The risk factors associated with mortality were age (OR 1.03, CI 95% 1.01-1.06), heart disease (OR 7.51, CI 95% 1.48-37.9), hemodialysis (OR 3.68, CI 95% 1.28-10.57), and use of corticosteroids (OR 2.83, CI 95% 1.01-7.92). The COVID-19 pandemic had an impact on the increase incidence of candidemia. The persistently high mortality highlights the need for better management strategies, control of risk factors, and guarantee of adequate treatment.

3.
Braz. j. biol ; 84: e263364, 2024. tab
Artigo em Inglês | VETINDEX | ID: biblio-1403862

RESUMO

Soaps play an important role in our hygiene and health, as they not only have a bactericidal effect but also remove dirt from the human body. To evaluate the effectiveness of soaps with antimicrobial activity from different commercial brands sold in Brazil. Tests of the antimicrobial activity of different soaps were carried out through diffusion in agar against the microorganisms Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Enterobacter cloacae, Acinetobacter baumannii, Proteus mirabilis, and Candida albicans. All commercial soaps tested transfer antimicrobial inhibition halo formation against S. aureus and P. aeruginosa bacteria. Only two commercial soaps inhibit the species A. baumannii and C. albicans. None of the seven products studied showed inhibition of E. cloacae, P. mirabilis, and E. coli bacteria. When comparing the information contained in the packaging of the products with the results obtained during a survey, divergences were observed. The soaps that provide greater efficiency against the tested microorganisms were presented in presentations 1 and 2, which become useful against the bacteria species S. aureus, P. aeruginosa, and A. baumannii and a fungus species C. albicans. Marks 3, 4, 5, 6, and 7 parallel the same sensitivity result opposite as bacteria of the species S. aureus and P. aeruginosa, with quantitative variation only of the inhibition halo. There was a divergence between the information contained in the packaging of the seven products under study and the results of the experimental tests.


Os sabonetes têm um papel importante para a nossa higiene e saúde, pois eles além de ter efeito bactericida, também removem as sujeiras presentes no corpo humano. Avaliar a eficácia de sabonetes com atividade antimicrobiana de diferentes marcas comerciais vendidas no Brasil. Foram realizados ensaios da atividade antimicrobiana dos diferentes sabonetes através do método difusão em ágar frente aos microrganismos Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Enterobacter cloacae, Acinetobacter baumannii, Proteus mirabilis e Candida albicans. Todos os sabonetes comerciais testados apresentaram formação de halo de inibição antimicrobiana frente às bactérias S. aureus e P. aeruginosa. Apenas dois sabonetes comerciais apresentaram inibição das espécies A. baumannii e C. albicans. Nenhum dos sete produtos estudados apresentou inibição das bactérias E. cloacae, P. mirabilis e E. coli. Na comparação das informações contidas nas embalagens dos produtos com os resultados obtidos durante a pesquisa realizada foram observadas divergências. Os sabonetes que apresentaram maior eficiência contra os microrganismos testados foram aqueles das apresentações 1 e 2, que se mostraram eficazes contra as espécies de bactérias S. aureus, P. aeruginosa e A. baumannii e contra a espécie de fungo C. albicans. As marcas 3, 4, 5, 6 e 7 apresentaram o mesmo resultado de sensibilidade frente as bactérias das espécies S. aureus e P. aeruginosa, com variação quantitativa apenas do halo de inibição. Houve divergência entre as informações contidas nas embalagens dos sete produtos em estudo e os resultados dos testes experimentais.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia
4.
Antibiotics (Basel) ; 12(1)2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36671292

RESUMO

In this study, seven different silver nanoparticles (AgNPs) were obtained using the fungi species from the phylum Ascomycota, Aspergillus tubingensis, Aspergillus spp., Cladosporium pini-ponderosae, Fusarium proliferatum, Epicoccum nigrum, Exserohilum rostratum, and Bionectria ochroleuca, isolated from the Brazilian biodiversity, particularly from the mangrove and Caatinga biomes. The nanoparticles were coded as AgNP-AT, AgNP-Asp, AgNP-CPP, AgNP-FP, AgNP-EN, AgNP-ER, and AgNP-BO and characterized using spectrophotometry (UV-Vis), dynamic light scattering (DLS), zeta potential, transmission electron microcopy (TEM), and Fourier-transform infrared (FTIR) spectroscopy. All the AgNPs presented homogeneous size in the range from 43.4 to 120.6 nm (DLS) and from 21.8 to 35.8 nm (TEM), pH from 4.5 to 7.5, negative charge, and presence of protein coating on their surface. The antifungal activity of the AgNPs was evaluated on clinical strains of Candida albicans, and on the non-albicans species, Candida krusei, Candida glabrata, Candida parapsilosis, Candida tropicalis, and Candida guilliermondii, common in hospital infections, and against the phytopathogens Fusarium oxysporum, Fusarium phaseoli, Fusarium sacchari, Fusarium subglutinans, Fusarium verticillioides, and Curvularia lunata, which are species responsible for serious damage to agriculture production. The AgNPs were effective against the yeasts with MICs ranging from 1.25 to 40 µM and on the phytopathogens with MICs from 4 to 250 µM, indicating the promising possibility of application of these AgNPs as antifungal agents. The results indicated that the physicochemical parameters of the AgNPs, including the functional groups present on their surface, interfered with their antifungal activity. Overall, the results indicate that there is no specificity of the AgNPs for the yeasts or for the phytopathogens, which can be an advantage, increasing the possibility of application in different areas.

5.
Ciênc. rural (Online) ; 53(8): e20220254, 2023. ilus
Artigo em Inglês | VETINDEX | ID: biblio-1418160

RESUMO

We described a case of cerebral infarction and thrombotic meningoencephalitis due to candidiasis in a seven-month-old calf. The death occurred three days after the onset of apathy, fever, and the head's lateral deviation to the left. Macroscopic changes in the brain consisted of asymmetry of telencephalic hemispheres; the right hemisphere was enlarged, causing cerebellar herniation. A focally extensive red area was observed on the surface of the right occipital lobe. At cross-sections of the fixed brain, the lesions revealed to be extensive, red-brown, soft or cavitated areas affecting the white and grey matter from the level of the thalamus to the cerebellum and compressing subjacent structures. Histologically, there was acute, coalescent, multifocal necrosupurative meningoencephalitis, associated with vasculitis, congestion, thrombosis, edema, infarction, and intralesional fungal hyphae. The diagnosis of cerebral infarction and thrombotic meningoencephalitis due to candidiasis was made by the pathological changes, the staining and morphological characteristics of the agent, and immunohistochemistry. The cerebral infarction and thrombotic meningoencephalitis in cattle can result from vascular lesions due to infection by Candida sp.; although uncommon, this case demonstrated that candidiasis should be part of a list of differential diagnoses of severe brain injuries in cattle.


Descreve-se um caso de infarto cerebral e meningoencefalite trombótica devido a candidíase em um bezerro de sete meses de idade. A morte ocorreu três dias após o início de apatia, febre e desvio lateral da cabeça para a esquerda. As alterações macroscópicas no cérebro consistiam em assimetria dos hemisférios telencefálicos; o hemisfério direito estava aumentado, causando herniação cerebelar. Uma extensa área vermelha focal foi observada na superfície do lobo occipital direito. Nos cortes transversais do encéfalo fixado, as lesões revelaram áreas extensas, marrom-avermelhadas, moles ou cavitadas, afetando a substância branca e cinzenta desde o nível do tálamo até o cerebelo e comprimindo as estruturas subjacentes. Histologicamente, havia meningoencefalite necrossupurativa multifocal aguda, coalescente, associada a vasculite, congestão, trombose, edema, infarto e hifas fúngicas intralesionais. O diagnóstico de infarto cerebral e meningoencefalite trombótica devido a candidíase foi feito pelas alterações patológicas, coloração e características morfológicas do agente e imuno-histoquímica. O infarto cerebral e meningoencefalite trombótica em bovinos pode resultar de lesões vasculares devido à infecção por Candida sp.; embora incomum, este caso demonstra que a candidíase deve fazer parte de uma lista de diagnósticos diferenciais de lesões cerebrais graves em bovinos.


Assuntos
Animais , Bovinos , Candidíase/complicações , Doenças dos Bovinos , Infarto Cerebral/veterinária , Traumatismo Cerebrovascular/veterinária , Meningoencefalite/veterinária
6.
Antibiotics, v. 12, n. 1, 91, jan. 2023
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-4761

RESUMO

In this study, seven different silver nanoparticles (AgNPs) were obtained using the fungi species from the phylum Ascomycota, Aspergillus tubingensis, Aspergillus spp., Cladosporium pini-ponderosae, Fusarium proliferatum, Epicoccum nigrum, Exserohilum rostratum, and Bionectria ochroleuca, isolated from the Brazilian biodiversity, particularly from the mangrove and Caatinga biomes. The nanoparticles were coded as AgNP-AT, AgNP-Asp, AgNP-CPP, AgNP-FP, AgNP-EN, AgNP-ER, and AgNP-BO and characterized using spectrophotometry (UV-Vis), dynamic light scattering (DLS), zeta potential, transmission electron microcopy (TEM), and Fourier-transform infrared (FTIR) spectroscopy. All the AgNPs presented homogeneous size in the range from 43.4 to 120.6 nm (DLS) and from 21.8 to 35.8 nm (TEM), pH from 4.5 to 7.5, negative charge, and presence of protein coating on their surface. The antifungal activity of the AgNPs was evaluated on clinical strains of Candida albicans, and on the non-albicans species, Candida krusei, Candida glabrata, Candida parapsilosis, Candida tropicalis, and Candida guilliermondii, common in hospital infections, and against the phytopathogens Fusarium oxysporum, Fusarium phaseoli, Fusarium sacchari, Fusarium subglutinans, Fusarium verticillioides, and Curvularia lunata, which are species responsible for serious damage to agriculture production. The AgNPs were effective against the yeasts with MICs ranging from 1.25 to 40 µM and on the phytopathogens with MICs from 4 to 250 µM, indicating the promising possibility of application of these AgNPs as antifungal agents. The results indicated that the physicochemical parameters of the AgNPs, including the functional groups present on their surface, interfered with their antifungal activity. Overall, the results indicate that there is no specificity of the AgNPs for the yeasts or for the phytopathogens, which can be an advantage, increasing the possibility of application in different areas.

7.
Pharmaceutics ; 14(3)2022 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-35335969

RESUMO

Fungal diseases affect more than 1 billion people worldwide. The constant global changes, the advent of new pandemics, and chronic diseases favor the diffusion of fungal pathogens such as Candida, Cryptococcus, Aspergillus, Trichophyton, Histoplasma capsulatum, and Paracoccidioides brasiliensis. In this work, a series of nitrofuran derivatives were synthesized and tested against different fungal species; most of them showed inhibitory activity, fungicide, and fungistatic profile. The minimal inhibitory concentration (MIC90) values for the most potent compounds range from 0.48 µg/mL against H. capsulatum (compound 11) and P. brasiliensis (compounds 3 and 9) to 0.98 µg/mL against Trichophyton rubrum and T. mentagrophytes (compounds 8, 9, 12, 13 and 8, 12, 13, respectively), and 3.9 µg/mL against Candida and Cryptococcus neoformans strains (compounds 1 and 5, respectively). In addition, all compounds showed low toxicity when tested in vitro on lung cell lines (A549 and MRC-5) and in vivo in Caenorhabditis elegans larvae. Many of them showed high selectivity index values. Thus, these studied nitrofuran derivatives proved to be potent against different fungal species, characterized by low toxicity and high selectivity; for these reasons, they may become promising compounds for the treatment of mycoses.

8.
J Fungi (Basel) ; 8(3)2022 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-35330261

RESUMO

The study of non-Saccharomyces yeasts in wine fermentations allows the exploration of new alternatives for the reduction of ethanol in wines. The objective of this work was to evaluate the fermentation capacity of two indigenous Candida yeasts (C. oleophila and C. boidinii) in monoculture and sequential fermentations (laboratory and microvinification scale) to produce Chilean Sauvignon Blanc wine. Fermentations were monitored by the determination of ethanol, glycerol, organic acids, and residual sugars. The results indicated that at the laboratory scale for both the monoculture and sequential fermentations it was possible to reduce the ethanol concentration on 0.77% v/v (monoculture) and 1.5% v/v (sequential) for C. oleophila and 0.50% v/v (monoculture) and 0.04% v/v (sequential) for C. boidinii compared to S. cerevisiae (12.87% v/v). Higher glycerol concentrations were produced in monoculture than sequential fermentations (C. oleophila: 9.47 g/L and C. boidinii 10.97 g/L). For microvinifications, the monoculture and sequential fermentations with C. boidinii managed to reduce ethanol content by 0.17% v/v and 0.54% v/v, respectively, over the S. cerevisiae control (13.74% v/v). In the case of C. oleophila, the reduction was only observed in sequential fermentations with 0.62% v/v. Interestingly, grapes with higher sugar concentration resulted in wines with lees ethanol concentrations. This might be associated to the use of C. oleophila (13.12% v/v) and C. boidinii (13.20% v/v) in sequential fermentations microvinification scale.

9.
Braz. j. biol ; 82: e265038, 2022. ilus, tab
Artigo em Inglês | VETINDEX | ID: biblio-1403820

RESUMO

Mangrove shrub Avicennia marina (Forsk.) Vierh was used to test the antifungal and antibacterial activities of aerial fractions in vitro. Aspergillus sp, Candida sp and Gram positive bacteria have all been found to be sensitive to mangrove extracts, whereas Gram negative bacteria have been found to be resistant to them. Agar disc diffusion and well-cut diffusion were employed to conduct antifungal and antibacterial activities. The MICs (minimum inhibitory concentrations) for each assay have been established. Several extracts from Mangrove reduced fungus growth (diameters fluctuated between 11 and 41 mm). The Ethyl acetate fraction showed particularly strong inhibition of C. tropicalis, C. albicanis, and A. fumigatus. They had 41, 40, and 25 mm-diameter inhibition zones, respectively. Nesoral, a synthetic antifungal medication, showed no significant changes in its MICs compared to different extracts. Enterococcus faecalis and Bacillus subtilis were inhibited by Petroleum Ether extracts at MICs of 0.78 and 0.35 mg/mL, respectively. It is possible that A. marina extracts may be exploited as a viable natural alternative that may be employed in the management of various infections, notably nosocomial bacterial infections, as anti-candidiasis and as anti-aspergillosis agents.


Arbusto de mangue Avicennia marina (Forsk.) Vierh foi usado para testar as atividades antifúngicas e antibacterianas de frações aéreas in vitro. As bactérias Aspergillus sp, Candida sp e Gram-positivas mostraram-se sensíveis aos extratos de mangue, enquanto as bactérias Gram-negativas mostraram-se resistentes a eles. Difusão em disco de ágar e difusão bem cortada foram empregadas para realizar atividades antifúngicas e antibacterianas. Para cada ensaio foram estabelecidas as CIMs (concentrações inibitórias mínimas). Vários extratos de mangue reduziram o crescimento do fungo (os diâmetros variaram entre 11 e 41 mm). A fração acetato de etila mostrou inibição particularmente forte de C. tropicalis, C. albicanis e A. fumigatus. Eles tinham zonas de inibição de 41, 40 e 25 mm de diâmetro, respectivamente. Nesoral, um medicamento antifúngico sintético, não apresentou alterações significativas em suas CIMs em comparação com diferentes extratos Enterococcus faecalis e Bacillus subtilis foram inibidos por extratos de éter de petróleo em MICs de 0,78 e 0,35 mg/mL, respectivamente. É possível que os extratos de A. marina possam ser explorados como uma alternativa natural viável que pode ser empregada no manejo de várias infecções, notadamente infecções bacterianas nosocomiais, como agentes anti-candidíase e anti-aspergilose.


Assuntos
Extratos Vegetais , Avicennia , Antibacterianos , Antifúngicos , Arábia Saudita , Oceano Índico
10.
Biointerface Res Appl Chem, v. 11, n. 6, p. 14764-14774, mar. 2021
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-3765

RESUMO

Biological silver nanoparticles (AgNPs) were synthesized using the marine endophytic fungus Aspergillus tubingensis and inhibited Bacillus subtilis biofilm formation at low concentrations. Cotton and polyester fabrics impregnated with AgNPs were analyzed by transmission electron microscopy (TEM), and the concentration of AgNPs in both fabrics was determined using inductivelycoupled plasma atomic emission spectrometry (ICP-AES). The fabrics carrying the AgNPs inhibited the Staphylococcus aureus and Escherichia coli growth by 100%. Both fabrics impregnated one time with AgNPs inhibited yeasts' clinical species' growth, Candida albicans, Candida glabrata, and Candida parapsilosis, from 80.1% to approximately 98.0%. Besides the anti-biofilm effect, the AgNPs impregnation process on cotton and polyester fabrics was highly efficient, and both fabrics presented antimicrobial effects against clinically relevant bacteria and yeast species. The results evidence that functionalized textiles containing these biological AgNPs can play an essential role in combating pathogenic microorganisms. Thereby offering an alternative to design effective solutions, mainly for hospital garments and biomedical devices, to avoid microorganisms transmissions and hospitalacquired nosocomial infections.

11.
Future Microbiol ; 15: 1001-1013, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32811174

RESUMO

Aim: To compare the pathogenesis of vulvovaginal candidiasis by three Candida species in diabetic mice. Materials & methods: Estrogenized and diabetic mice were challenged with C. albicans, C. tropicalis and C. glabrata. Results: Diabetic animals infected with C. albicans and C. tropicalis maintained the highest fungal burden, despite of high levels of proinflammatory cytokines (IL-6 and TNF-α), respectively. For C. glabrata, the results were similar in diabetic and nondiabetic groups. Conclusion:C. tropicalis was as invasive as C. albicans, and both were more effective than C. glabrata. This ability was attributed to filamentation, which may be stimulated by glucose levels from vaginal fluid. In addition, the high burden may be attributed to the apparent immunological inefficiency of the diabetic host.


Assuntos
Candida albicans/fisiologia , Candida glabrata/fisiologia , Candida tropicalis/fisiologia , Candidíase Vulvovaginal/microbiologia , Complicações do Diabetes/microbiologia , Animais , Candida albicans/genética , Candida albicans/isolamento & purificação , Candida glabrata/genética , Candida glabrata/isolamento & purificação , Candida tropicalis/genética , Candida tropicalis/isolamento & purificação , Candidíase Vulvovaginal/etiologia , Candidíase Vulvovaginal/genética , Candidíase Vulvovaginal/metabolismo , Complicações do Diabetes/etiologia , Complicações do Diabetes/genética , Complicações do Diabetes/metabolismo , Modelos Animais de Doenças , Feminino , Humanos , Interleucina-6/genética , Interleucina-6/metabolismo , Camundongos , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
12.
Microb Pathog ; 149: 104394, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32707317

RESUMO

Candidiasis is the most common fungal infection affecting hospitalized patients, especially immunocompromised and critical patients. Limitations regarding the assertive diagnosis of both Candidemia and Candidiasis not only impairs the introduction of effective treatments but also lays a heavy financial burden over the health system. Furthermore, it is still challenging to ascertain whether diagnostic methods are accurate and whether treatment is effective for patients with Candidemia. These constraints come from the uncertainty of the pathophysiological mechanism by which the pathogen establishes the opportunistic infection. Additionally, it is the reason why some patients present positive blood culture results, and others do not, and why it is very difficult during clinical routines to prove Candidemia or invasive candidiasis. Taking into account the current situation, this contribution proposes two markers that may help to understand the mechanisms of infection by the pathogen: Leukotriene F4 and 5,6-dihydroxy-eicosatetraenoic. These two lipids putatively modulate the host's immune response, and the initial data presented in this contribution suggest that these lipids allow the opportunistic infection to be installed. The study was carried out using an omics-based platform using direct-infusion high-resolution mass spectrometry and allied with bioinformatics tools to provide accurate and reliable results for biomarker candidates screening.


Assuntos
Candidemia , Candidíase , Infecções Oportunistas , Antifúngicos/uso terapêutico , Candida , Candidemia/diagnóstico , Candidíase/diagnóstico , Candidíase/tratamento farmacológico , Humanos , Leucotrienos
13.
Future Microbiol ; 15: 521-539, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32476467

RESUMO

Aim: Elucidate the antifungal efficacy of biologically synthesized silver nanoparticles with ethanolic propolis extract (AgNPs PE) against the planktonic forms and biofilms of clinically important fungi. Materials & methods: AgNPs were synthesized, characterized and evaluated for cytotoxicity, mutagenicity and antimicrobial activity. Results: AgNPs PE displayed a colloidal appearance, good stability and size of 2.0-40.0 nm. AgNPs PE demonstrated lower cytotoxicity and nonmutagenic potential. In addition, AgNPs PE displayed antifungal properties against all tested isolates, inhibiting growth at concentrations lower than the cytotoxic effect. Mature biofilms treated for 48 h with AgNPs PE showed significant reduction of viable cells, metabolic activity and total biomass. Conclusion: This is the first time that AgNPs have been synthesized from an ethanolic extract of propolis only, proving antifungal, antibiofilm, atoxic and nonmutagenic properties.


Assuntos
Antifúngicos/toxicidade , Nanopartículas Metálicas/toxicidade , Micoses/microbiologia , Própole/química , Prata/toxicidade , Antifúngicos/química , Biofilmes/efeitos dos fármacos , Candida/efeitos dos fármacos , Candida/fisiologia , Fusarium/efeitos dos fármacos , Fusarium/fisiologia , Humanos , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Micoses/tratamento farmacológico , Prata/química
14.
Curr Pharm Des ; 26(14): 1556-1565, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32183660

RESUMO

BACKGROUND: Vaginal infections caused by non-albicans species have become common in women of all age groups. The resistance of species such as Candida parapsilosis to the various antifungal agents is a risk factor attributed to these types of infections, which instigates the search for new sources of active compounds in vulvovaginal candidiasis (VCC) therapy. OBJECTIVE: This study evaluated the antifungal activity of Syngonanthus nitens Bong. (Ruhland) derivatives and employed a lipid nanoemulsion as a delivery system.' METHODS: In this study, a lipid nanoemulsion was employed as a delivery system composed of Cholesterol (10%), soybean phosphatidylcholine: Brij 58 (1: 2) and PBS (pH 7.4) with the addition of 0.5% of a chitosan dispersion (80%), and evaluated the antifungal activity of S. nitens Bong. (Ruhland) derivatives against planktonic cells and biofilms of Candida parapsilosis. By a biomonitoring fractionation, the crude extract (EXT) and one fraction (F2) were selected and incorporated into a lipid nanoemulsion (NL) composed of cholesterol (10%), a 1:2 mixture of soybean phosphatidylcholine:polyoxyethylene -20- cetyl ether (10%), and phosphate buffer solution (pH 7.4) with a 0.5% chitosan dispersion (80%). The NL presented a diameter size between 50-200 nm, pseudoplastic behavior, and positive charge. The EXT and five fractions were active against planktonic cells. RESULTS AND DISCUSSION: The incorporation of EXT and F2 into the NL increased antifungal activity and enhanced the anti-biofilm potential. This study classified the use of an NL as an important tool for the administration of S. nitens derivatives in cases of infections caused by this C. parapsisilosis. CONCLUSION: This work concluded that S. nitens derivatives were important sources of active molecules against C. parapsilosis and the use of a lipid nanoemulsion was an important tool to promote more effective F2 release and to improve the antifungal activity aiming the control of C. parapsilosis infections.


Assuntos
Antifúngicos/farmacologia , Candidíase Vulvovaginal , Eriocaulaceae , Antifúngicos/química , Antifúngicos/uso terapêutico , Biofilmes , Candida parapsilosis , Candidíase Vulvovaginal/tratamento farmacológico , Feminino , Humanos , Lipídeos/química , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Extratos Vegetais/farmacologia
15.
Sci Total Environ ; 703: 134779, 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-31710846

RESUMO

The search for natural substances such as plant extracts with antimicrobial properties has considerably increased, given that biofilms constitute a barrier against antifungal therapy, where these can be formed on any surface, such as acrylic resin prosthesis. The objective of this study was to identify the chemical composition of the Persea americana Mill. leaf ethanol extract (EEFPa) using the UPLC-QTOF-MS/MS technique, to verify its antifungal activity through a sensitivity test according to the conditions described in the documents in M27-A3 (CLSI, 2008) and M60 (CLSI, 2017), to induce biofilm formation in acrylic resin discs and quantify their formation using tetrazolium salt reduction (MTT), as well as to treat these with the extract and fluconazole. Ten of the twelve compounds present in the extract were identified. In the sensitivity test the lowest minimum inhibitory concentration observed was 512 µg/mL, while fluconazole concentrations ranged from 64 to 1 µg/mL. During biofilm induction, all the isolates were able to form biofilms within 48 h. During biofilm treatment, the extract was less effective at biofilm reduction than Fluconazole. The EEFPa showed significant antifungal activity against some of the strains in this study, however the extract showed lower effect when compared to fluconazole against the biofilm formation.


Assuntos
Persea , Resinas Acrílicas , Antifúngicos , Biofilmes , Produtos Biológicos , Candida , Testes de Sensibilidade Microbiana , Folhas de Planta , Espectrometria de Massas em Tandem , Árvores
16.
Front Microbiol ; 10: 2642, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31803166

RESUMO

We have previously reported on the activity of different extracts from Astronium sp. against Candida albicans, with the hydroethanolic extract prepared from leaves of A. urundeuva, an arboreal species widely distributed in arid environments of South America and often used in folk medicine, displaying the highest in vitro activity. Here we have further evaluated the antifungal activity of this extract against strains of C. albicans and C. glabrata, the two most common etiological agents of candidiasis. The extract was tested alone and loaded into a nanostructured lipid system (10% oil phase, 10% surfactant and 80% aqueous phase, 0.5% Poloxamer 407®). In vitro susceptibility assays demonstrated the antifungal activity of the free extract and the microemulsion against both Candida species, with increased activity against C. glabrata, including collection strains and clinical isolates displaying different levels of resistance against the most common clinically used antifungal drugs. Checkerboard results showed synergism when the free extract was combined with amphotericin B against C. albicans. Serial passage experiments confirmed development of resistance to fluconazole but not to the free extract upon prolonged exposure. Although preformed biofilms were intrinsically resistant to treatment with the extract, it was able to inhibit biofilm formation by C. albicans at concentrations comparable to those inhibiting planktonic growth. Cytotoxicity assays in different cell lines as well as an alternative model using Artemia salina L. confirmed a good safety profile of the both free and loaded extracts, and an in vivo assay demonstrated the efficacy of the free and loaded extracts when used topically in a rat model of vaginal candidiasis. Overall, these results reveal the promise of the A. urundeuva leaves extract to be further investigated and developed as an antifungal.

17.
Antibiotics (Basel) ; 8(4)2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31817228

RESUMO

Candida sp. treatment has become a challenge due to the formation of biofilms which favor resistance to conventional antifungals, making the search for new compounds necessary. The objective of this study was to identify the composition of the Licania rigida Benth. leaf ethanolic extract and to verify its antifungal activity against Candida sp. and its biofilms. The composition identification was performed using the ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS/MS) technique. The antifungal activity of extract and fluconazole against planktonic cells and biofilms was verified through the minimum inhibitory concentration (MIC) following biofilm induction and quantification in acrylic resin discs by reducing tetrazolic salt, with all isolates forming biofilms within 48 h. Six constituents were identified in the extract, and the compounds identified are derivatives from phenolic compounds such as flavonoids (epi) gallocatechin Dimer, epigallocatechin and gallocatechin, Myricetin-O-hexoside, Myricitrin, and Quercetin-O-rhamnoside. The extract reduced biofilm formation in some of the strains analyzed, namely C. tropicalis URM5732, C. krusei INCQS40042, and C. krusei URM6352. This reduction was also observed in the treatment with fluconazole with some of the analyzed strains. The extract showed significant antifungal and anti-biofilm activities with some of the strains tested.

18.
Antibiotics (Basel) ; 8(4)2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31618883

RESUMO

Candida is a genus of yeasts and is the most common cause of fungal infections worldwide. However, only a few antifungal drugs are currently available for the treatment of Candida infections. In the last decade, terpenophenols have attracted much attention because they often possess a variety of biological activities. In the search for new antifungals, eight carveoylphenols were synthesized and characterized by spectroscopic analysis. By using the broth microdilution assay, the compounds were evaluated for antifungal activities in vitro against four human pathogenic yeast, and structure-activity relationships (SAR) were derived. Noteworthy, in this preliminary study, compounds 5 and 6, have shown a significant reduction in the growth of all Candida strains tested. Starting from these preliminary results, we have designed the second generation of analogous in this class, and further studies are in progress in our laboratories.

19.
Rev. Soc. Bras. Med. Trop ; Rev. Soc. Bras. Med. Trop;52: e20180152, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1041546

RESUMO

Abstract INTRODUCTION: Introducing new antibiotics to the clinic is critical. METHODS: We adapted a plate method described by Kawaguchi and coworkers in 20131 for detecting inhibitory airborne microorganisms. RESULTS: We obtained 51 microbial colonies antagonist to Chromobacterium violaceum, purified and retested them, and of these, 39 (76.5%) were confirmed. They comprised 24 bacteria, 13 fungi, and 2 yeasts. Among the fungi, eight (61.5%) produced active extracts. Among the bacterial, yeast, and fungal strains, 17 (44.7%) and 12 (31.6%) were active against Candida albicans and Candida parapsilosis, respectively. CONCLUSIONS: The proposed screening method is a rapid strategy for discovering potential antibiotic producers.


Assuntos
Bactérias/isolamento & purificação , Candida/efeitos dos fármacos , Chromobacterium/efeitos dos fármacos , Microbiologia do Ar , Percepção de Quorum , Fungos/isolamento & purificação , Antibacterianos/isolamento & purificação , Bactérias/metabolismo , Contagem de Colônia Microbiana , Fungos/metabolismo , Antibacterianos/metabolismo , Antibacterianos/farmacologia
20.
PeerJ ; 6: e5476, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30402343

RESUMO

Medicinal plants play a crucial role in the search for components that are capable of neutralizing the multiple mechanisms of fungal resistance. Psidium salutare (Kunth) O. Berg is a plant native to Brazil used as both food and traditional medicine to treat diseases and symptoms such as stomach ache and diarrhea, whose symptoms could be related to fungal infections from the genus Candida. The objective of this study was to investigate the influence of seasonal variability on the chemical composition of the Psidium salutare essential oil, its antifungal potential and its effect on the Candida albicans morphogenesis. The essential oils were collected in three different seasonal collection periods and isolated by the hydrodistillation process in a modified Clevenger apparatus with identification of the chemical composition determined by gas chromatography coupled to mass spectrometry (GC/MS). The antifungal assays were performed against Candida strains through the broth microdilution method to determine the minimum fungicidal concentration (MFC). Fungal growth was assessed by optical density reading and the Candida albicans dimorphic effect was evaluated by optical microscopy in microculture chambers. The chemical profile of the essential oils identified 40 substances in the different collection periods with γ-terpinene being the predominant constituent. The antifungal activity revealed an action against the C. albicans, C. krusei and C. tropicalis strains with an IC50 ranging from 345.5 to 2,754.2 µg/mL and a MFC higher than 1,024 µg/mL. When combined with essential oils at sub-inhibitory concentrations (MIC/16), fluconazole had its potentiated effect, i.e. a synergistic effect was observed in the combination of fluconazole with P.salutare oil against all Candida strains; however, for C. albicans, its effect was reinforced by the natural product in all the collection periods. The results show that the Psidium salutare oil affected the dimorphic transition capacity, significantly reducing the formation of hyphae and pseudohyphae in increasing concentrations. The results show that P. salutare oil exhibits a significant antifungal activity against three Candida species and that it can act in synergy with fluconazole. These results support the notion that this plant may have a potential use in pharmaceutical and preservative products.

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