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1.
Chem Biodivers ; 17(2): e1900580, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31913571

RESUMO

Developing effective and eco-friendly antimicrobials and pesticides has become a highly important issue. The repellent, insecticidal and antimicrobial activity of essential oils (EOs) isolated by hydrodistillation from dried leaves of the three Eucalyptus species (E. cloeziana, E. umbellata and E. benthamii) were investigated. During GC/MS analysis, α-pinene (47.36 %), 1,8-cineol (38.53 %) and α-pinene (35.31 %) were identified as major components of E. cloeziana, E. umbellata and E. benthamii, respectively. The EOs from E. cloeziana exhibited the longest effective protection time (465 min, at 50.0 % w/w) for humans among the EOs studied. The effective protection time was 30 min and 300 min at concentrations of 12.5 % (w/w) and 25.0 % (w/w), respectively. Fumigating insecticidal activity of EOs from three Eucalyptus species was tested by airtight fumigation in conical flask, which indicated that essential oils had a highly and rapidly insecticidal activity on Culex pipiens quinquefasciatus. The antimicrobial activity of EOs was evaluated by using disc diffusion and agar dilution methods. There was no significant difference in the antibacterial activity of EOs from E. cloeziana and E. umbellate and they had the same MICs (20 mL/L) on Staphylococcus aureus, Salmonella typhi, Bacillus subtilis and Escherichia coli. E. benthamii had the worst microbial inhibitory effect among the three Eucalyptus essential oils and the MIC value for the test species is 40 mL/L except for Rhodotorula Harrison (10 mL/L).


Assuntos
Anti-Infecciosos/química , Eucalyptus/química , Repelentes de Insetos/química , Inseticidas/química , Óleos Voláteis/química , Folhas de Planta/metabolismo , Animais , Anti-Infecciosos/farmacologia , Aspergillus/efeitos dos fármacos , Candida/efeitos dos fármacos , Culex/efeitos dos fármacos , Eucalyptus/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Repelentes de Insetos/farmacologia , Testes de Sensibilidade Microbiana , Óleos Voláteis/análise , Óleos Voláteis/farmacologia , Folhas de Planta/química
2.
Med Chem ; 16(1): 128-139, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30501601

RESUMO

BACKGROUND: It is assumed that the unfavorable selective toxicity of an antifungal drug Amphotericin B (AmB) can be improved upon chemical modification of the antibiotic molecule. OBJECTIVE: The aim of this study was verification of the hypothesis that introduction of bulky substituents at the amino sugar moiety of the antibiotic may result in diminishment of mammalian in vitro toxicity of thus prepared AmB derivatives. METHODS: Twenty-eight derivatives of AmB were obtained upon chemical modification of the amino group of mycosamine residue. This set comprised 10 N-succinimidyl-, 4 N-benzyl-, 5 Nthioureidyl- and 9 N-aminoacyl derivatives. Parameters characterizing biological in vitro activity of novel compounds were determined. RESULTS: All the novel compounds demonstrated lower than AmB antifungal in vitro activity but most of them exhibited negligible cytotoxicity against human erythrocytes and three mammalian cell lines. In consequence, the selective toxicity of majority of novel antifungals, reflected by the selective toxicity index (STI = EH50/IC50) was improved in comparison with that of AmB, especially in the case of 5 compounds. The novel AmB derivatives with the highest STI, induced substantial potassium efflux from Candida albicans cells at concentrations slightly lower than IC50s but did not trigger potassium release from human erythrocytes at concentrations lower than 100 µg/mL. CONCLUSION: Some of the novel AmB derivatives can be considered promising antifungal drug candidates.


Assuntos
Anfotericina B/farmacologia , Antifúngicos/farmacologia , Hexosaminas/farmacologia , Anfotericina B/síntese química , Anfotericina B/química , Antifúngicos/síntese química , Antifúngicos/química , Aspergillus/efeitos dos fármacos , Candida/efeitos dos fármacos , Cryptococcus/efeitos dos fármacos , Relação Dose-Resposta a Droga , Fusarium/efeitos dos fármacos , Hexosaminas/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Mucor/efeitos dos fármacos , Rhizopus/efeitos dos fármacos , Relação Estrutura-Atividade
3.
Chem Biodivers ; 17(2): e1900624, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31863703

RESUMO

In search for new fungicidal and free radical scavenging agents, we synthesized a focused library of 2-chloroquinoline based monocarbonyl analogs of curcumin (MACs). The synthesized MACs were evaluated for in vitro antifungal and antioxidant activity. The antifungal activity was evaluated against five different fungal strains such as Candida albicans, Fusarium oxysporum, Aspergillus flavus, Aspergillus niger, and Cryptococcus neoformans, respectively. Most of the synthesized MACs displayed promising antifungal activity compared to the standard drug Miconazole. Furthermore, molecular docking study on a crucial fungal enzyme sterol 14α-demethylase (CYP51) could provide insight into the plausible mechanism of antifungal activity. MACs were also screened for in vitro radical scavenging activity using butylated hydroxytoluene (BHT) as a standard. Almost all MACs exhibited better antioxidant activity compared to BHT.


Assuntos
Antifúngicos/síntese química , Antioxidantes/química , Curcumina/análogos & derivados , Proteínas Fúngicas/metabolismo , Simulação de Acoplamento Molecular , Quinolinas/química , Antifúngicos/metabolismo , Antifúngicos/farmacologia , Aspergillus/efeitos dos fármacos , Sítios de Ligação , Candida albicans/efeitos dos fármacos , Domínio Catalítico , Cryptococcus neoformans/efeitos dos fármacos , Curcumina/metabolismo , Curcumina/farmacologia , Proteínas Fúngicas/química , Testes de Sensibilidade Microbiana , Esterol 14-Desmetilase/química , Esterol 14-Desmetilase/metabolismo
5.
Pak J Pharm Sci ; 32(4): 1679-1686, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31608890

RESUMO

Four fungal isolates were identified in this study of which three were Aspergillus species with Aspergillus flavus having the highest frequency followed by A. parasiticus. The result of high frequency of Aspergillus flavus and Aspergillus parasiticus in the Zea mays sample revealed production of aflatoxins. Maize sample in Awka was found to contain aflatoxin B1 (9.60ppb) and B2 (13.3ppb). Inhibition of A. flavus and A. parasiticus with Azadirachta indica and Garcinia kola seed extracts showed that the test plant extracts were effective for reducing mycelial growth on the test organism. Methanolic extract of G. kola showed antifungal inhibitory activity on the test organisms and the highest at 10% concentration. With ethanol extracts of G. kola, the antifungal activity was effective i.e. for inhibition of A. flavus and A. parasiticus, with A. parasiticus having the higher percentage inhibition at 10%. Inhibiting growth of Aspergillus flavus and Aspergillus parasiticus using methanolic and ethanolic extracts of neem seeds was effective in the inhibition of the test organism at 10%. The methanolic and ethanolic extracts of combined Garcinia kola and neem seeds revealed effective inhibition of A. flavus and A. parasiticus with ethanolic extracts of the combined test plants exerting the highest inhibition against A. flavus (80.43±3.62). The extracts from this plant show the ability to suppress growth of toxigenic A. flavus and A. parasiticus. Phytochemical analysis showed that the methanolic and ethanolic extracts of G. kola and neem seeds showed the presence of secondary metabolites and this may be a reason for the inhibitory activity on A. flavus and A. parasiticus. Results from this study will be important in planning a management strategy against aflatoxin-producing fungi and other fungi associated with spoilage of stored food products.


Assuntos
Aflatoxinas/metabolismo , Antifúngicos/farmacologia , Aspergillus/metabolismo , Azadirachta/química , Garcinia kola/química , Zea mays/microbiologia , Aflatoxinas/análise , Antifúngicos/química , Aspergillus/efeitos dos fármacos , Aspergillus/isolamento & purificação , Aspergillus/patogenicidade , Etanol/química , Microbiologia de Alimentos , Armazenamento de Alimentos , Metanol/química , Testes de Sensibilidade Microbiana , Nigéria , Compostos Fitoquímicos/análise , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Sementes/microbiologia
6.
Artigo em Inglês | MEDLINE | ID: mdl-31599694

RESUMO

Ochratoxin A (OTA) is a secondary metabolite produced by filamentous fungi species belonging to the genera Penicillium and Aspergillus. The contamination of grapes by ochratoxigenic species occurs worldwide in regions of tropical and temperate climates. Better control of fungal growth is achieved through good cultural practice and proper selection of fungicides. Kresoxim-methyl and famoxadone are the most common fungicides used in vineyards. This study aimed at analysing the OTA production and toxigenic potential of Aspergillus carbonarius under fungicide treatment with famoxadone and kresoxim-methyl. The growth rate of A. carbonarius was evaluated by measuring the glucosamine content and the diameter of the fungal colonies. OTA production was quantified by HPLC analysis. The treatment with fungicides, kresoxim-methyl and famoxadone, significantly reduced the fungal growth, by 76% and 60%, respectively. However, the mycotoxin production was greater in the fungicide-treated groups than the control group, showing that even though the fungicides were effective in controlling fungal growth, they were ineffective against mycotoxin production.


Assuntos
Aspergillus/efeitos dos fármacos , Fungicidas Industriais/toxicidade , Estrobilurinas/toxicidade , Aspergillus/crescimento & desenvolvimento , Contaminação de Alimentos/análise , Fungicidas Industriais/análise , Estrobilurinas/análise
7.
Mycoses ; 62(11): 1049-1055, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31479538

RESUMO

Antifungal treatment options for allergic bronchopulmonary aspergillosis (ABPA) and severe asthma with fungal sensitisation (SAFS) are largely limited to itraconazole based on the outcome of randomised controlled trials. It is unclear if nebulised amphotericin B deoxycholate (Fungizone® ) is a viable therapeutic option. We evaluated the safety and efficacy of nebulised Fungizone® in the long-term treatment of various forms of pulmonary aspergillosis. We assessed the records of 177 patients with various forms of pulmonary aspergillosis attending the National Aspergillosis Centre in Manchester who had received Fungizone® . Patients first received a challenge test with nebulised Fungizone® in hospital with spirometry pre/post-Fungizone® and nebulised salbutamol given pre-Fungizone® . Tolerability and changes in Aspergillus IgE, Aspergillus IgG and total IgE were evaluated. Sixty-six per cent (117/177) were able to tolerate the test dose of Fungizone® and in all cases, the reason for discontinuation of the first test dose was worsening breathlessness. Twenty six (21%) stopped therapy within 4-6 weeks, and the commonest reason cited for discontinuation of therapy was increased breathlessness, hoarseness and cough. Eighteen (10.2%) patients continued the Fungizone® for >3 months of which 5 (27.8%) recorded an improvement in total IgE, Aspergillus-specific IgE and Aspergillus IgG. Eleven had ABPA, four had SAFS, two had Aspergillus bronchitis and one had Aspergillus sensitisation with cavitating nodules. Among these 18 patients, sputum fungal culture results went from positive to negative in five patients, became positive in one patient, remained positive in three patients, and remained negative in seven patients. Nebulised Fungizone® appears to be a poorly tolerated treatment for pulmonary Aspergillosis with high dropout rates. There appears to be both clinical and serological benefits following sustained treatment with nebulised Fungizone® in some patients.


Assuntos
Anfotericina B/uso terapêutico , Antifúngicos/uso terapêutico , Ácido Desoxicólico/uso terapêutico , Adesão à Medicação/estatística & dados numéricos , Nebulizadores e Vaporizadores , Aspergilose Pulmonar/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Anfotericina B/efeitos adversos , Anticorpos Antifúngicos/sangue , Antifúngicos/efeitos adversos , Aspergillus/efeitos dos fármacos , Ácido Desoxicólico/efeitos adversos , Vias de Administração de Medicamentos , Combinação de Medicamentos , Avaliação de Medicamentos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Reino Unido , Adulto Jovem
8.
Mycoses ; 62(11): 1064-1068, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31368588

RESUMO

To analyse and discuss the clinical features and pathogenic characteristics, diagnosis and treatment of patients with otomycosis in southern China. Two hundred fifty-six patients from southern China diagnosed with otomycosis were randomly separated into two groups: the drug filling group and drug smearing group. Patients in the drug filling group were first examined and then had the pathogenic secretions in their external auditory canals cleared by otoendoscopy. Then, the local antifungal cream triamcinolone acetonide clotrimazole was injected into the external auditory canal. The same treatment was undertaken 1 week later and repeated once or twice more. Patients in the drug smearing group were also treated by otoendoscopy. Then, they were told to smear their external auditory canals once per day with the antifungal cream. All cases were followed for more than 6 months after the 3- to 4-week treatment. The main symptoms and otoendoscopic examination were used to evaluate the prognosis. Aspergillus was the commonest fungus. The cure rate was 93% in the drug filling group and 81% in the drug smearing group. Otomycosis is very common in southern China, but it lacks characteristic features in its early stages. Once diagnosed, the local lesions in the external auditory canal should be cleared thoroughly using otoendoscopy, and then, the local antifungal cream is injected into external auditory canal. The cure rate can be significantly improved with the foregoing treatment.


Assuntos
Antifúngicos/uso terapêutico , Meato Acústico Externo/microbiologia , Otomicose/diagnóstico , Otomicose/tratamento farmacológico , Adolescente , Adulto , Idoso , Aspergilose/complicações , Aspergilose/diagnóstico , Aspergillus/efeitos dos fármacos , Criança , Pré-Escolar , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
9.
Artigo em Inglês | MEDLINE | ID: mdl-31437087

RESUMO

Food decay by spoilage fungi leads to significant economic losses and hazards to consumers' health due to the potential of mycotoxin occurrence. Ochratoxin A (OTA) is a mycotoxin known as nephrotoxic and carcinogenic to humans. Natural capsaicin was evaluated for its effectiveness against the growth of five Aspergillus section Nigri strains and accumulation of OTA in inoculated black grapes. Results showed that capsaicin was effective in inhibiting fungal growth and OTA production by new four Aspergillus section Nigri strains (ATHUM 6997, 6998, 6999, 7000) and by Aspergillus carbonarius as well. Moreover, capsaicin addition exhibited maximum inhibition of OTA produced by ATHUM 6997, 6998, 6999, and 7000 in black grapes at 28.9%, 8.6%, 68.4%, and 78.1%, respectively. Inhibition percentage of OTA production by A. carbonarius in grapes treated with capsaicin was estimated at 61.5%. These results suggest that capsaicin influences the OTA biosynthesis pathway of all Aspergillus section Nigri strains and therefore could be used as an effective natural preservative against OTA contamination of vineyards. Risk assessment revealed that when grapes are treated with capsaicin, consumers are less exposed to OTA.


Assuntos
Antifúngicos/farmacologia , Aspergillus/efeitos dos fármacos , Capsaicina/farmacologia , Ocratoxinas/antagonistas & inibidores , Vitis/microbiologia , Antifúngicos/química , Antifúngicos/metabolismo , Aspergillus/química , Aspergillus/crescimento & desenvolvimento , Capsaicina/química , Capsaicina/metabolismo , Testes de Sensibilidade Microbiana , Ocratoxinas/metabolismo
10.
Artigo em Inglês | MEDLINE | ID: mdl-31294650

RESUMO

The present study examines the influence of the natural preservatives carvacrol, eugenol, trans-cinnamaldehyde and the essential oil (EO) Origanum vulgare on ochratoxin A (OTA) production and the mycelial growth of two food-related moulds, Penicillium verrucosum and Aspergillus westerdijkiae, by broth macro-dilution assay for 21 days. With the addition of ½ minimum inhibitory concentration (MIC) carvacrol, eugenol and O. vulgare EO, the mycelial dry weight of both moulds decreased significantly over the whole incubation period of 7, 14 and 21 days. Trans-cinnamaldehyde slightly stimulated the growth of A. westerdijkiae and P. verrucosum at 14 and 21 days of incubation. Growth inhibition did not accompany inhibition of OTA production. Although the growth of both moulds was inhibited after the addition of ½ MIC carvacrol, eugenol and O. vulgare EO, the OTA production of the strong mycotoxin producer A. westerdijkiae was stimulated. Only trans-cinnamaldehyde inhibited the production of OTA with the addition of ½ MIC. P. verrucosum produced significantly less OTA than A. westerdijkiae, and its mycotoxin production was almost completely inhibited by the addition of ½ MIC of the natural preservatives.


Assuntos
Aspergillus/efeitos dos fármacos , Microbiologia de Alimentos , Conservantes de Alimentos/farmacologia , Micélio/efeitos dos fármacos , Ocratoxinas/biossíntese , Penicillium/efeitos dos fármacos , Acroleína/análogos & derivados , Acroleína/química , Acroleína/farmacologia , Aspergillus/química , Eugenol/química , Eugenol/farmacologia , Conservantes de Alimentos/química , Monoterpenos/química , Monoterpenos/farmacologia , Micélio/crescimento & desenvolvimento , Ocratoxinas/química , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Penicillium/química
11.
Food Chem ; 298: 125080, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31260985

RESUMO

Propolis extract was investigated as potential substitute for sorbate in orangeade. Extract was prepared by using aqueous solution of hydroxypropyl-beta-cyclodextrins. Propolis extract was incorporated in non-carbonated orange soft drinks and its antioxidant activity, microbiological stability and color changes were estimated and compared to those of orangeade containing potassium sorbate. l-Ascorbic acid (AsA) degradation at concentrations 0.13 and 1.3% w/w was investigated in the presence of propolis during storage using High Performance Liquid Chromatography-Ion Exclusion Column (HPLC-IEC). The results indicate that the rate of degradation decreased with an increase in ascorbic acid concentration, while addition of propolis affected the degradation rate of samples containing a high AsA concentration. The antifungal effect of propolis extract, potassium sorbate and their combination was assayed. Results showed the inhibition of Aspergillus spp. and B. bruxellensis inhibited in low combined concentrations antimicrobials, while Aspergillus spp. and T. macrosporus were inhibited at 450 mg/g propolis extract.


Assuntos
Bebidas , Conservação de Alimentos/métodos , Conservantes de Alimentos/química , Própole/química , Anti-Infecciosos , Antifúngicos/farmacologia , Antioxidantes/química , Ácido Ascórbico/análise , Ácido Ascórbico/química , Aspergillus/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão/métodos , Cor , Microbiologia de Alimentos , Extratos Vegetais/química , Própole/farmacologia , Ácido Sórbico/farmacologia
12.
Int J Food Microbiol ; 306: 108258, 2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31362161

RESUMO

Propionic acid is widely used as a preservative in (poultry) feed. In this study we have isolated and identified fungal strains from nine samples poultry feed originating from different countries. The majority of the strains were Aspergilli with a eurotium-morph, such as Aspergillus proliferans and A. chevalieri. These and three other species were selected and tested for their sensitivity towards the feed preservative propionic acid, among them Penicillium lanosocoeruleum. The determined MIC values of 6.1-31 mM of these poultry feed specific fungi were well in the range as described in literature. Propionic acid (at 31 mM) damages conidia (spores) in a species dependent fashion after a 24-hour-treatment. The majority of the conidia (over 70%) of P. lanosocoeruleum germinated within 60 h on agar medium, while 50 and 80% of the A. chevalieri and A. proliferans conidia did not, respectively. Dependent on the species, cell damage was visible after incubation with propionic acid. Germ tubes of P. lanosocoeruleum in a biofilm showed extensive (85%) cell death after a 30 min treatment with propionic acid and slightly lower sensitivity was observed with A. proliferans (62% cell death). Microscopic analysis of these fungal biofilms revealed extensive damage to the cell membrane and showed distorted intracellular structures. Fluorescent life-dead staining of the germ tubes showed a clear dose response of propionic acid indicating a fungicidal effect on these growing cells. These results show that conidia can be inactivated by propionic acid, but that germ tubes show a much higher sensitivity. These observations shed new light on the mode of action of this important preservative to prevent fungal contamination of feed.


Assuntos
Ração Animal/microbiologia , Aspergillus/efeitos dos fármacos , Fungicidas Industriais/farmacologia , Penicillium/efeitos dos fármacos , Propionatos/farmacologia , Esporos Fúngicos/efeitos dos fármacos , Animais , Aspergillus/classificação , Aspergillus/isolamento & purificação , Biofilmes/efeitos dos fármacos , Meios de Cultura/farmacologia , Eurotium , Microbiologia de Alimentos/métodos , Testes de Sensibilidade Microbiana , Penicillium/classificação , Penicillium/isolamento & purificação , Aves Domésticas
13.
J Pept Sci ; 25(7): e3175, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31264322

RESUMO

Due to the increasing incidence of fungal opportunistic infections and emergence of antibiotic-resistant fungal strains, antimicrobial peptides (AMPs) are considered as ideal candidates for antifungal compounds. In silico methods can reduce the limitations of natural AMPs such as toxicity and instability and improve their antimicrobial properties and selectivity. In this study, we designed AurH1, a new truncated peptide, based on the six-amino acid sequence of Aurein1.2. Further, the antimicrobial activities and toxicity effects of AurH1 on human skin fibroblast cells and red blood cells were investigated. Finally, field emission scanning electron microscopy (FE-SEM) and flow cytometry were performed in order to study the mechanism of action of AurH1. The results indicated that AurH1 had only antifungal activity (at a minimal inhibitory concentration (MIC) of 7.3-125 µg/mL) without any antibacterial effects on the selected bacteria, while Aurein1.2 had both antifungal and antibacterial activities as positive control. Furthermore, AurH1 did not show any toxicity on Hu02 cells and human red blood cells at its MIC range. In conclusion, it became clear that AurH1 is a selective peptide against fungi with no toxic effects on the selected bacteria and human cells.


Assuntos
Anti-Infecciosos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Anti-Infecciosos/síntese química , Anti-Infecciosos/química , Peptídeos Catiônicos Antimicrobianos/síntese química , Peptídeos Catiônicos Antimicrobianos/química , Aspergillus/efeitos dos fármacos , Candida/efeitos dos fármacos , Cryptococcus neoformans/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Microsporum/efeitos dos fármacos , Penicillium/efeitos dos fármacos , Saccharomyces cerevisiae/efeitos dos fármacos , Trichophyton/efeitos dos fármacos
14.
Molecules ; 24(14)2019 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-31337014

RESUMO

Ochratoxin A (OTA) is a mycotoxin with a serious impact on human health. In Mediterranean countries, the black Aspergilli group, in particular Aspergillus carbonarius, causes the highest OTA contamination. Here we describe the synthesis of three polyphenolic flavonoids: 5-hydroxy-6,7-dimethoxy-flavone (MOS), 5,6-dihydroxy-7-methoxy-flavone (NEG), and 5,6 dihydroxy-flavone (DHF), as well as their effect on the prevention of OTA biosynthesis and lipoxygenase (LOX) activity in A. carbonarius cultured in a conducive liquid medium. The best control effect on OTA biosynthesis was achieved using NEG and DHF. In fungal cultures treated with these compounds at 5, 25, and 50 µg/mL, OTA biosynthesis significantly decreased throughout the 8-day experiment. NEG and DHF appear to have an inhibiting effect also on the activity of LOX, whereas MOS, which did not significantly inhibit OTA production, had no effect on LOX activity. The presence of free hydroxyls in catecholic position in the molecule appears to be a determining factor for significantly inhibiting OTA biosynthesis. However, the presence of a methoxy group in C-7 in NEG could slightly lower the molecule's reactivity increasing OTA inhibition by this molecule at 5 µg/mL. Polyphenolic flavonoids present in edible plants may be easily synthesized and used to control OTA biosynthesis.


Assuntos
Aspergillus/efeitos dos fármacos , Aspergillus/metabolismo , Flavonoides/síntese química , Flavonoides/farmacologia , Ocratoxinas/biossíntese , Vias Biossintéticas/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Flavonas/química , Flavonas/farmacologia , Flavonoides/química , Lipoxigenase/metabolismo , Micotoxinas
15.
Food Microbiol ; 83: 59-63, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31202419

RESUMO

Information on the sensitivity of spoilage fungi of bakery products to sanitizing agents is scarce in the literature. Thus, the aim of this study was to evaluate the antifungal activity of different classes of commercial sanitizers, which have permitted use in the food industry, on the main fungi involved in spoiling bakery products. The tests were carried out according to the protocol for testing the antifungal effect of chemical sanitizers of the European Committee for Standardization (CEN), with adaptations. Different strains of six isolated fungal species responsible for spoiling bakery products (Penicillium roqueforti, Penicillium paneum, Hyphopichia burtonii, and Aspergillus pseudoglaucus) were tested against five sanitizers at three concentrations: benzalkonium chloride (0.3%, 2.5%, 5%), biguanide (2%, 3.5%, 5%), peracetic acid (0.15%, 1.5%, 3%), quaternary ammonium (0.3%, 2.5%, 5%), and sodium hypochlorite (0.01%, 0.1%, 0.2%). Peracetic acid was the most effective sanitizes considering the genera, species, and concentrations evaluated, generally being capable of reductions between 2 and 4 logs of initial control tested. Biguanide should not be the compound of choice when the main goal of the bakery industry is fungal control.


Assuntos
Aspergillus/efeitos dos fármacos , Pão/microbiologia , Desinfetantes/farmacologia , Microbiologia de Alimentos , Fungicidas Industriais/farmacologia , Penicillium/efeitos dos fármacos , Biguanidas/farmacologia , Conservação de Alimentos , Testes de Sensibilidade Microbiana , Ácido Peracético/farmacologia
16.
Clin Microbiol Infect ; 25(9): 1096-1113, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31158517

RESUMO

SCOPE: Presenting symptoms, distributions and patterns of diseases and vulnerability to invasive aspergillosis (IA) are similar between children and adults. However, differences exist in the epidemiology and underlying conditions, the usefulness of newer diagnostic tools, the pharmacology of antifungal agents and in the evidence from interventional phase 3 clinical trials. Therefore, the European Society for Clinical Microbiology and Infectious Diseases (ESCMID) and the European Confederation of Medical Mycology (ECMM) have developed a paediatric-specific guideline for the diagnosis and management of IA in neonates and children. METHODS: Review and discussion of the scientific literature and grading of the available quality of evidence was performed by the paediatric subgroup of the ESCMID-ECMM-European Respiratory Society (ERS) Aspergillus disease guideline working group, which was assigned the mandate for the development of neonatal- and paediatric-specific recommendations. QUESTIONS: Questions addressed by the guideline included the epidemiology of IA in neonates and children; which paediatric patients may benefit from antifungal prophylaxis; how to diagnose IA in neonates and children; which antifungal agents are available for use in neonates and children; which antifungal agents are suitable for prophylaxis and treatment of IA in neonates and children; what is the role of therapeutic drug monitoring of azole antifungals; and which management strategies are suitable to be used in paediatric patients. This guideline provides recommendations for the diagnosis, prevention and treatment of IA in the paediatric population, including neonates. The aim of this guideline is to facilitate optimal management of neonates and children at risk for or diagnosed with IA.


Assuntos
Antifúngicos/uso terapêutico , Aspergilose/diagnóstico , Aspergilose/tratamento farmacológico , Infecções Fúngicas Invasivas/diagnóstico , Infecções Fúngicas Invasivas/tratamento farmacológico , Antibioticoprofilaxia/métodos , Antibioticoprofilaxia/normas , Aspergillus/efeitos dos fármacos , Criança , Gerenciamento Clínico , Monitoramento de Medicamentos , Humanos , Recém-Nascido
17.
Diagn Microbiol Infect Dis ; 95(2): 166-170, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31174994

RESUMO

The present study was to determine the in vitro activity of posaconazole (POS) against 385 Candida and 268 Aspergillus clinical isolates from China. We found that POS was active against 85.5% Candida and 94.4% Aspergillus isolates. Non-wild-type (non-WT) phenotype was found in a subset of Candida albicans (15.4%), Candida tropicalis (11.9%), Aspergillus fumigatus (4.1%), and Aspergillus flavus (17.4%) isolates. Cross-resistance to POS and other triazoles was seen. Gene sequencing showed that 4 C. albicans, 1 C. tropicalis, and 9 A. fumigatus isolates with cross-resistance to POS and other triazoles had mutations in ERG11 or CYP51A. In conclusion, POS has potent in vitro activity against most of Candida and Aspergillus isolates from China. Non-WT phenotype and those with cross-resistance to POS and other triazoles exist, frequently driven by mutations of ERG11 in Candida spp. and CYP51A in Aspergillus spp.


Assuntos
Aspergillus/efeitos dos fármacos , Candida/efeitos dos fármacos , Sistema Enzimático do Citocromo P-450/genética , Farmacorresistência Fúngica Múltipla/genética , Proteínas Fúngicas/genética , Micoses/microbiologia , Triazóis/farmacologia , Antifúngicos/farmacologia , Aspergillus/genética , Aspergillus/isolamento & purificação , Candida/genética , Candida/isolamento & purificação , China , Farmacorresistência Fúngica Múltipla/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Mutação
19.
Int. microbiol ; 22(2): 239-246, jun. 2019. ilus, graf, tab
Artigo em Inglês | IBECS | ID: ibc-184830

RESUMO

Silver nanoparticles (SN) have been recently developed as a new class of antimicrobial agents against numerous pathogenic microorganisms. SN have also been used as efficient drug delivery systems and have been linked with increasing drug potency. Here, we demonstrated the enhanced antifungal efficacy of nystatin (NYT) and fluconazole (FLU) after conjugation with SN. The antifungal bioactivity of NYT- and FLU-coated SN was evaluated against Candida albicans ATCC 10231 and Aspergillus brasiliensis ATCC 16404 by the agar tube dilution method. The aim of this study was to determine and compare the antifungal efficacy of NYT and FLU with their SN and, finally, the combination of both nanoparticles as NYT-SN + FLU-SN against pathogenic fungi. The results indicated that all test samples showed a dose-dependent response against tested fungi. SN significantly enhanced the antifungal effects of NYT and FLU as compared to drugs alone. We observed a remarkable increase in the percent inhibition of both fungi (90-100%) when treated with a combination of both nanoparticles NYT-SN + FLU-SN at 200 μg/mL only. Furthermore, the morphological modifications occurred at the surface of fungal species were also analyzed by atomic force microscopy (AFM) and scanning electron microscopy (SEM). While tested against primary human cell line, all SN showed negligible cytotoxicity. Hence, these results suggest that the combination of SN with NYT and FLU may have clinical implications in the treatment of fungal infections. However, in vivo studies are needed before recommending the use of these nanoparticles safely in clinical situations


No disponible


Assuntos
Antifúngicos/farmacologia , Aspergillus/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Sinergismo Farmacológico , Nanopartículas Metálicas , Prata/farmacologia , Fluconazol/farmacologia , Nistatina/farmacologia , Aspergillus/ultraestrutura , Candida albicans/ultraestrutura , Testes de Sensibilidade Microbiana , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Propriedades de Superfície/efeitos dos fármacos
20.
J Agric Food Chem ; 67(22): 6212-6221, 2019 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-31099566

RESUMO

Common soil fungi, Aspergillus flavus and Aspergillus parasiticus, are opportunistic pathogens that invade preharvest peanut seeds. These fungi often produce carcinogenic aflatoxins that pose a threat to human and animal health through food chains and cause significant economic losses worldwide. Detection of aflatoxins and further processing of crops are mandated to ensure that contaminated agricultural products do not enter food channels. Under favorable conditions, the fungus-challenged peanut seeds produce phytoalexins, structurally related stilbenoids, capable of retarding fungal development. The purpose of the present study was to evaluate the potential influence of peanut phytoalexins on fungal development and aflatoxin formation in the course of peanut-fungus interaction. The present research revealed that during such interaction, aflatoxin formation was completely suppressed in A. flavus and A. parasiticus strains tested, when low concentrations of spores were introduced to wounded preincubated peanuts. In most of the experiments, when fungal spore concentrations were 2 orders of magnitude higher, the spores germinated and produced aflatoxins. Of all experimental seeds that showed fungal growth, 57.7% were aflatoxin-free after 72 h of incubation. The research provided new knowledge on the aflatoxin/phytoalexin formation in the course of peanut-fungus interaction.


Assuntos
Aflatoxinas/biossíntese , Arachis/microbiologia , Aspergillus/metabolismo , Sementes/química , Estilbenos/farmacologia , Arachis/química , Arachis/metabolismo , Aspergillus/efeitos dos fármacos , Aspergillus/crescimento & desenvolvimento , Interações Hospedeiro-Parasita , Doenças das Plantas/microbiologia , Sementes/metabolismo , Sementes/microbiologia , Sesquiterpenos/metabolismo , Sesquiterpenos/farmacologia , Esporos Fúngicos/efeitos dos fármacos , Esporos Fúngicos/crescimento & desenvolvimento , Esporos Fúngicos/metabolismo , Estilbenos/metabolismo
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