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1.
Mycotoxin Res ; 36(1): 103-114, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31512221

RESUMO

Canadian oat harvest samples, deliveries to processors, and train shipments from primary elevators were collected from mid-2014 through mid-2017 and analyzed for 26 mycotoxins and the fungal biomarker ergosterol. Of the 26 mycotoxins, 7 were not detected in any sample. The most frequently measured mycotoxins were beauvericin (in over 95% of samples analyzed), followed by tentoxin, culmorin, alternariol, alternariol methyl ether, and deoxynivalenol. Median concentrations of the Fusarium-produced mycotoxins ranged from 68 to 1142 µg/kg for deoxynivalenol, 39 to 188 µg/kg for HT-2 and T-2 toxins, 66 to 232 µg/kg for nivalenol, and less than 35 µg/kg for beauvericin. Median concentrations of the sum of Alternaria-produced mycotoxins were all less than 250 µg/kg. Concentrations of analytes varied among years, as well as among growing areas, for the harvest samples. Ergosterol, Fusarium, and Alternaria mycotoxin concentrations appeared to increase from the west toward the eastern Prairies and the province of Quebec; the differences were not statistically significant though. Ochratoxin A in deliveries and train shipments showed annual cyclic increases in the late summer. The results of the survey demonstrate the general compliance of Canadian oats with existing maximum levels for mycotoxins and indicate that in late summer and in years with increased Fusarium infection, there can be a need for monitoring of ochratoxin A and deoxynivalenol, respectively, to mitigate risks of noncompliant grain.


Assuntos
Avena/química , Grão Comestível/química , Ergosterol/análise , Micotoxinas/análise , Alternaria/metabolismo , Aspergillus/metabolismo , Avena/microbiologia , Canadá , Depsipeptídeos/análise , Contaminação de Alimentos/análise , Fusarium/metabolismo , Penicillium/metabolismo , Peptídeos Cíclicos/análise , Medição de Risco , Estações do Ano , Sesquiterpenos/análise
2.
Future Microbiol ; 14: 1221-1233, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31625442

RESUMO

Aim: This study investigated the effect of terpinen-4-ol against Sporothrix schenckii complex and its interactions with antifungals. Materials & methods: The antifungal activity of terpinen-4-ol was evaluated by broth microdilution. The potential effect on cellular ergosterol concentration was evaluated by spectrophotometry. The antibiofilm activity was evaluated by violet crystal staining and XTT reduction assay. The potential pharmacological interactions with antifungals were evaluated by the checkerboard assay. Results: terpinen-4-ol (T-OH) showed minimal inhibitory concentrations ranging from 4 to 32 mg/l decreasing cellular ergosterol content and presented a SMIC ranging from 64 to 1024 mg/l for Sporothrix spp. The combinations of T-OH with itraconazole or terbinafine were synergistic. Conclusion: T-OH has antifungal activity against Sporothrix spp. and acts synergistically with standard antifungals.


Assuntos
Antifúngicos/farmacologia , Biofilmes/efeitos dos fármacos , Sporothrix/efeitos dos fármacos , Sporothrix/crescimento & desenvolvimento , Terpenos/farmacologia , Sinergismo Farmacológico , Ergosterol/análise , Testes de Sensibilidade Microbiana
3.
Food Funct ; 10(10): 6633-6643, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31555775

RESUMO

In this study, we investigated the potential bioactivities of an ethanol extract of Hericium novae-zealandiae and four of its constituents, namely hericenone C, hericene B, ergosterol and ergosterol peroxide. The proliferation of three prostate cancer cell lines, namely DU145, LNCaP and PC3, was evaluated after treatment with the extract and constituents. It was found that both the ethanol extract and ergosterol peroxide possess anti-proliferative activities to the three prostate cancer cell lines. Ergosterol peroxide was considered likely to be one of the major compounds responsible for the anti-proliferative effect of the ethanol extract. Subsequently, the results of RT-qPCR assay showed two possible mechanisms for these anti-proliferative activities. One is apoptosis, supported by the up-regulation of CASP3, CASP8, CASP9, and an increase in the ratio of Bax/Bcl2. The other is anti-inflammation, indicated by the down-regulation of IL6 and up-regulation of IL24. The ethanol extract also exhibited antioxidant and AChE inhibitory (though weak) activities. However, none of the four compounds were found to account for these latter two activities. This is the first report of the bioactivities, and the corresponding active ingredients of lipophilic constituents from H. novae-zealandiae.


Assuntos
Agaricales/química , Extratos Vegetais/análise , Extratos Vegetais/farmacologia , Apoptose/efeitos dos fármacos , Caspases/genética , Caspases/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ergosterol/análise , Ergosterol/isolamento & purificação , Ergosterol/farmacologia , Humanos , Interleucina-6/genética , Interleucina-6/metabolismo , Interleucinas/genética , Interleucinas/metabolismo , Nova Zelândia , Fenóis/análise , Fenóis/isolamento & purificação , Fenóis/farmacologia , Extratos Vegetais/isolamento & purificação
4.
J Mycol Med ; 29(3): 210-218, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31400863

RESUMO

OBJECTIVE: The rise in fungal infections is alarming due to emergence of multidrug drug resistance (MDR). Hence elucidating novel drug targets to circumvent the problem of MDR warrants immediate attention. This study analyzes the effect of retrograde (RTG) signaling disruption on major MDR mechanisms and virulence of the human pathogenic fungal species Candida albicans. MATERIAL AND METHODS: Drug transporter activity was measured by rhodamine 6G (R6G) efflux. Membrane damage was studied by propidium iodide intake and ergosterol level determination. Cell wall effect was estimated by quantifying chitin levels and cell sedimentation rate. Biofilm formation was visualized by calcoflour white and crystal violet staining and measured by dry mass and MTT assay. Cell adherence to buccal epithelial cell was determined by trypan blue staining and MTT assay. Virulence was studied using nematode model Caenorhabditis elegans. RESULT: We demonstrated that mutant of transcription factor CaRTG3 leads to impaired efflux activity of ATP Binding Cassette (ABC) superfamily multidrug transporters. We further uncover that rtg3 mutant exhibited a disrupted membrane, decreased ergosterol levels and increased chitin content. Furthermore, RTG signaling disruption leads to inhibited biofilm formation and cell adherence to buccal epithelial cells. Lastly, rtg3 mutant displayed a reduced infectivity in C. elegans illustrating its vulnerability as antifungal target. Interestingly, all the abrogated phenotypes could be rescued in the revertant strain of rtg3 mutant. CONCLUSION: Present study establishes a link between RTG signaling, drug efflux and biofilm formation and validates CaRTG3 as antifungal target. Intricate studies are needed to further understand and exploit this therapeutic opportunity.


Assuntos
Biofilmes/crescimento & desenvolvimento , Candida albicans/metabolismo , Quitina/análise , Ergosterol/análise , Proteínas de Membrana Transportadoras/genética , Transdução de Sinais , Animais , Transporte Biológico , Caenorhabditis elegans/microbiologia , Candida albicans/genética , Candida albicans/patogenicidade , Candidíase/microbiologia , Modelos Animais de Doenças , Proteínas de Membrana Transportadoras/metabolismo , Virulência
5.
Zhongguo Zhong Yao Za Zhi ; 44(10): 1978-1982, 2019 May.
Artigo em Chinês | MEDLINE | ID: mdl-31355550

RESUMO

Online gradient extraction-high performance liquid chromatography( HPLC) method was developed for simultaneous determination of high and low polar components in Cordyceps. The sample powder of Cordyceps was uniformly mixed with diatomaceous earth,packed into extraction tank,and installed into the HPLC system. Online gradient extraction was conducted with mobile phase at 70 ℃. The separation was performed on Zorbax SB-AQ( 4. 6 mm×150 mm,5 µm) column with 0. 1% formic acid solution-methanol as the mobile phase for gradient elution at 1. 0 mL·min~(-1). The column temperature was 30 ℃,and detection wavelength was set at 260 nm. The results showed that the high and low polar components in Cordyceps could be simultaneously extracted and separated by the developed method. Meanwhile,six high polar compounds( uracil,uridine,thymine,inosine,guanosine and adenosine) and one low polar compound( ergosterol) were identified by comparison with the reference peaks. The established method is rapid,stable and environment friendly,which is helpful to improve the quality evaluation level for Cordyceps.


Assuntos
Cromatografia Líquida de Alta Pressão , Cordyceps/química , Ergosterol/análise , Nucleosídeos/análise
6.
Food Chem ; 297: 124988, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31253285

RESUMO

Agaricus blazei, Auricularia fuscosuccinea and Pleurotus albidus mycelia were obtained in solid-state cultivation (SSC), using grains (brown rice, canjica corn and wheat) as raw material. Colonized grain flours were analysed for their nutritional, physical and physico-chemical characteristics and biological activity in vitro. Wheat flour with P. albidus showed higher values for protein (18.34 g/100 g), ergosterol (0.60 mg/g), mycelial biomass (183 mg/g) and total amino acids (58.34 mg/g). Corn flour with A. fuscosuccinea showed the highest total phenolic content (2.38 mg GAE/g), antioxidant activity in the 1,1-diphenyl-2-picrylhydrazyl (DPPH) (8.90 µmol TEAC/g) and 2,2'-Azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) (16.52 µmol TEAC/g) assay. Wheat flour with P. albidus were more effective at inhibiting of pancreatic lipase (74.5%) and of α-glucosidase (98.2%). In conclusion, grains colonized by macrofungi mycelia through SSC can enrich the nutritional value and the biological activity of the flours, which presents a potential for functional foods.


Assuntos
Agaricus/fisiologia , Farinha/análise , Valor Nutritivo , Pleurotus/fisiologia , Aminoácidos/química , Antioxidantes/química , Biomassa , Ergosterol/análise , Lipase/antagonistas & inibidores , Lipase/metabolismo , Oryza/metabolismo , Fenóis/análise , Triticum/metabolismo , Zea mays/metabolismo , alfa-Glucosidases/química , alfa-Glucosidases/metabolismo
7.
Food Microbiol ; 82: 504-514, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31027812

RESUMO

As a result of the rapidly growing human population, reducing post-harvest crop losses of cereals due to microbial pests has major importance. Plant defensins have the potential to fulfil these demands, being highly specific and efficient antimicrobial agents. Hence, this study aimed to extract and characterise a peptide from cowpea seeds and investigate its antifungal performance. After extraction and partial purification, N-terminal sequencing was used to identify the primary peptide in the extract as cowpea-thionin II. Antifungal activity in vitro was found against Fusarium culmorum (MIC = 50 µg/mL), but Aspergillus niger and Penecillium expansum showed an MIC > 500 µg/mL. The extract was resistant against heat treatment (100 °C, 15 min) but lost its antifungal activity in presence of cations (Na+, K+, Ca2+ and Mg2+, respectively). Membrane permeabilization of fungal hyphae was evident at 25 µg/mL, while induction of oxidative stress only had minor contribution to the antifungal performance. The extract did not induce haemolysis at all concentrations tested (up to 200 µg/mL). Finally, it was successfully used to protect stored wheat grains from fungal spoilage (determined via ergosterol content) when applied at 100 µg/mL. In conclusion, the defensin Cp-thionin II showed the potential for future application as food bio-preservative.


Assuntos
Antifúngicos/farmacologia , Conservantes de Alimentos/farmacologia , Fungos/efeitos dos fármacos , Proteínas de Plantas/farmacologia , Tioninas/farmacologia , Vigna/química , Antifúngicos/química , Antifúngicos/isolamento & purificação , Cátions , Permeabilidade da Membrana Celular/efeitos dos fármacos , Defensinas/química , Defensinas/isolamento & purificação , Defensinas/farmacologia , Grão Comestível/microbiologia , Ergosterol/análise , Ergosterol/metabolismo , Microbiologia de Alimentos , Conservantes de Alimentos/química , Conservantes de Alimentos/isolamento & purificação , Fungos/metabolismo , Fungos/fisiologia , Temperatura Alta , Hifas/efeitos dos fármacos , Hifas/metabolismo , Hifas/fisiologia , Testes de Sensibilidade Microbiana , Proteínas de Plantas/química , Proteínas de Plantas/isolamento & purificação , Estabilidade Proteica , Sementes/química , Tioninas/química , Tioninas/isolamento & purificação
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 217: 113-121, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-30928836

RESUMO

A new withanolide named as withacoagulin J (1) along with a known withanolide H (2) from Withania coagulans Dunal are reported in this paper. The isolated compounds were elucidated by using 1D-NMR (1H NMR, 13C NMR) and 2D-NMR including homonuclear (COSY, NOESY) and heteronuclear (HSQC, HMBC); along with Mass spectrometry, UV-Visible and IR spectroscopic techniques. The molecular formula based on Fast-Atom Bombardment Mass Spectrometry [FAB-MS (M + 1)] for 1 and 2 were deduced as C28H37O5 and C28H39O6 with m/z values 453.2624 and 471.6041, respectively. The quantum mechanical studies of both compounds are based on DFT calculations. The DFT studies show band gaps of 4.86 and 4.83 eV for 1 and 2, respectively. The band gaps of 1 and 2 reflect high stability and resistivity towards oxidation-reduction reactions. The energies of HOMO and LUMO for compound 1 are -6.11 and -1.25 eV and for compound 2: -6.47 and -1.64 eV respectively. Theoretical and experimental FTIR data closely match for both the compounds which support the high accuracy of the computational protocol selection. Other parameters such as bond lengths, bond angles and dihedral angles for both compounds are also studied.


Assuntos
Ergosterol/análise , Modelos Teóricos , Extratos Vegetais/química , Withania/química , Vitanolídeos/análise , Vitanolídeos/isolamento & purificação , Ergosterol/análogos & derivados , Ergosterol/química , Ergosterol/isolamento & purificação , Teoria Quântica , Vitanolídeos/química
9.
Food Chem ; 278: 760-766, 2019 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-30583439

RESUMO

Mushroom production and consumption is increasing, but high perishability still represents a major commercial drawback. Besides increasing the product shelf-life, conservation processes should be innocuous to consumers. Therefore, the effects of gamma and electron beam radiation on chemical and nutritional composition of fresh samples of Agaricus bisporus Portobello (a highly commercialized species) were assessed. Mushrooms were irradiated at 1, 2 or 5 kGy, and analyzed at different times (0, 4 and 8 days). In general, irradiation type had higher effect than irradiation dose. Gamma irradiation was associated with higher contents in sugars and ergosterol, while the 5 kGy dose, independently of irradiation source, was linked with higher protein levels. Nonetheless, irradiation might represent an effective preservation methodology for Portobello mushrooms, as it was effective in maintaining their chemical profiles (except for minor organic acids and saturated fatty acids) throughout the assayed time intervals.


Assuntos
Agaricus , Irradiação de Alimentos/métodos , Agaricus/química , Agaricus/efeitos da radiação , Relação Dose-Resposta à Radiação , Elétrons , Ergosterol/análise , Armazenamento de Alimentos/métodos , Raios gama , Proteínas de Plantas/análise , Fatores de Tempo
10.
Molecules ; 23(12)2018 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-30501053

RESUMO

With the goal of obtaining a novel bioactive compound with significant antifungal activity, a series of 1,3,4-thiadiazole derivatives (3a⁻3l) were synthesized and characterized. Due to thione-thiol tautomerism in the intermediate compound 2, type of substitution reaction in the final step was determined by two-dimensional (2D) NMR. In vitro antifungal activity of the synthesized compounds was evaluated against eight Candida species. The active compounds 3k and 3l displayed very notable antifungal effects. The probable mechanisms of action of active compounds were investigated using an ergosterol quantification assay. Docking studies on 14-α-sterol demethylase enzyme were also performed to investigate the inhibition potency of compounds on ergosterol biosynthesis. Theoretical absorption, distribution, metabolism, and excretion (ADME) predictions were calculated to seek their drug likeness of final compounds. The results of the antifungal activity test, ergosterol biosynthesis assay, docking study, and ADME predictions indicated that the synthesized compounds are potential antifungal agents, which inhibit ergosterol biosynthesis probably interacting with the fungal 14-α-sterol demethylase.


Assuntos
Antifúngicos/síntese química , Antifúngicos/farmacologia , Tiadiazóis/síntese química , Tiadiazóis/farmacologia , Antifúngicos/química , Candida/efeitos dos fármacos , Ergosterol/análise , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Tiadiazóis/química
11.
Mycologia ; 110(6): 1017-1032, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30481136

RESUMO

Mineral weathering plays an important role in poor-nutrient environments such as mine spoils and tailings. Ectomycorrhizal (ECM) fungi are able to enhance mineral weathering through different mechanisms, thereby increasing the availability of minerals and nutrients to plants. Six ECM fungi (Cadophora finlandia, Cenococcum geophilum, Hebeloma crustuliniforme, Lactarius aurantiosordidus, Paxillus involutes, and Tricholoma scalpturatum) were tested here for their tolerance to biotite-quartz-rich mine tailings. Either solid- or liquid-medium methods were used for in vitro selection of ECM fungi for their ability to grow on mine tailings. ECM fungi were selected based on their mycelial radial growth and metabolite production (ergosterol and low-molecular-mass organic acids, LMMOAs). We found a strong correlation between fungal ergosterol content and mycelial radial growth using the solid-medium method. However, the liquid-medium method was more appropriate for ergosterol synthesis and permitted direct measurement of organic acid production. We found that LMMOAs were exuded by ECM fungi, which solubilized mine tailings for their own growth and nutrition. Finally, we concluded that the ECM fungi C. finlandia and T. scalpturatum are the species most tolerant to tailings and could potentially improve the survival rate, growth, and health of white spruce seedlings planted on biotite mine spoils and tailings.


Assuntos
Silicatos de Alumínio/metabolismo , Biodegradação Ambiental , Biomassa , Meios de Cultura/química , Compostos Ferrosos/metabolismo , Micorrizas/crescimento & desenvolvimento , Micorrizas/metabolismo , Adaptação Fisiológica , Ergosterol/análise , Mineração , Micélio/crescimento & desenvolvimento , Micélio/metabolismo , Filogenia , Picea/microbiologia , Raízes de Plantas/microbiologia , Plântula/microbiologia
12.
J Agric Food Chem ; 66(24): 5971-5983, 2018 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-29869500

RESUMO

Pleurotus ostreatus, P. eryngii, and P. nebrodensis were cultivated on nonconventional substrates containing grape marc (GMC) or olive mill byproducts (OMB); wheat straw (WHS) served as control. GMC-based media demonstrated equal/better mushroom productivity than WHS for P. eryngii and P. nebrodensis, while the cultivation performance of P. eryngii was improved in OMB-based media. Both GMC and OMB substrates led to large increase of fruit-bodies content in phenolic acids, resveratrol, triterpenic compounds, and ergosterol; in particular, P. eryngii mushrooms presented significantly more total phenolics and exhibited much higher antioxidant activity (2- to 8-fold increase). Furthermore, substrates containing GMC or OMB presented up to 27% increase in mushroom ß-glucans. Overall, Pleurotus species responded in a different and mostly substrate-specific manner by selectively absorbing organic compounds. Phenolics and squalene content of substrates correlated very well with mushrooms antioxidant activity and ergosterol, respectively; the same was observed for triterpenics' content of substrates and mushrooms.


Assuntos
Olea/química , Pleurotus/crescimento & desenvolvimento , Vitis/química , Resíduos/análise , Meios de Cultura/química , Meios de Cultura/metabolismo , Ergosterol/análise , Hidroxibenzoatos/análise , Olea/metabolismo , Pleurotus/química , Pleurotus/metabolismo , Resveratrol , Estilbenos/análise , Vitis/metabolismo , beta-Glucanas/análise
13.
Molecules ; 23(5)2018 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-29747400

RESUMO

The rise in the number of fungal infections is requiring the rapid development of novel antifungal agents. A new polyoxovanadate functionalized by Zn-fluconazole coordination complexes, Zn3(FLC)6V10O28·10H2O (ZnFLC) (FLC = fluconazole) has been synthesized and evaluated for in vitro antifungal against Candida species. The identity of ZnFLC were confirmed by elemental analysis, IR spectrum, and single-crystal X-ray diffraction. The antifungal activities of ZnFLC was screened in 19 Candida species strains using the microdilution checkerboard technique. The minimum inhibitory concentration (MIC80) value of ZnFLC is 4 µg/mL on the azole-resistant clinical isolates of C. albicans HL973, which is lower than the positive control, FLC. The mechanism of ZnFLC against C. albicans HL973 showed that ZnFLC damaged the fungal cell membrane and reduced the ergosterol content. The expression of ERG1, ERG7, ERG11 ERG27, and ERG28, which have effects on the synthesis of ergosterol, were all significantly upregulated by ZnFLC.


Assuntos
Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Complexos de Coordenação/farmacologia , Fluconazol/farmacologia , Viabilidade Microbiana/efeitos dos fármacos , Vanadatos/farmacologia , Zinco/química , Antifúngicos/química , Vias Biossintéticas/genética , Candida/genética , Candida/crescimento & desenvolvimento , Candida/isolamento & purificação , Complexos de Coordenação/química , Ergosterol/análise , Ergosterol/biossíntese , Fluconazol/química , Genes Fúngicos , Testes de Sensibilidade Microbiana , Microscopia de Fluorescência , Vanadatos/química
14.
Food Funct ; 9(3): 1465-1474, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29488518

RESUMO

In recent years, mycosterols have emerged as potential functional ingredients for the development of sterol-enriched food products and dietary supplements. Agaricus blazei is a mushroom rich in bioactive compounds. For commercial purposes, their fruiting bodies must obey rigid morphological criteria. Those not conforming to these criteria are usually discarded, although this does not mean impairment of their content in bioactives. The aim of the present work was to propose the use of commercially discarded A. blazei fruiting bodies for obtaining an extract rich in ergosterol as a fortifier ingredient for yogurts. For extraction, the Soxhlet technology was used and the highest ergosterol yield (around 12%) was achieved in the 5th cycle, yielding 58.53 ± 1.72 µg of ergosterol per 100 g of mushroom (dry weight). The ergosterol rich extract presented notable antioxidant and antimicrobial properties, besides showing no hepatotoxicity. When added to the yogurts it significantly enhanced their antioxidant properties. Furthermore, it did not significantly alter the nutritional or the individual fatty acid profiles of the final dairy products. Thus, A. blazei fruiting bodies that do not conform to the commercial requirements of the market and are normally discarded could be exploited for obtaining a natural high added-value food additive, following the circular bioeconomy concept.


Assuntos
Agaricus/química , Ergosterol/isolamento & purificação , Ingredientes de Alimentos/análise , Conservação de Alimentos/métodos , Conservantes de Alimentos/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Verduras/química , Iogurte/análise , Antioxidantes/análise , Ergosterol/análise , Ácidos Graxos/análise , Conservantes de Alimentos/análise , Valor Nutritivo , Extratos Vegetais/análise , Ultrassom
15.
J Microbiol Methods ; 148: 49-54, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29580983

RESUMO

Ergosterol, total phospholipid fatty acid (PLFA) and linoleic acid (18:2n-6) have all been used to determine fungal growth. This paper compares these methods to assess the growth of four different saprotrophic fungal species during solid state cultivation using a wheat straw substrate that have not been compared or measured previously. Ergosterol production appeared to track the mycelia growth well but its production differed considerably between fungi. This means that a specific conversion factor needs to be determined and applied for any given fungus. In comparison, measurements of total PLFA and linoleic acid only showed promise for determining the growth of Postia placenta due to the positive correlation with ergosterol measurements. In contrast, the other fungi tested (Phanerochaete chrysosporium, Serpula lacrymans and Schizophyllum commune) showed either no correlation or in some cases a negative correlation using this assay. The novel findings highlight the variation in fungal fatty acid between species, culture conditions and durations of incubation; suggesting that measurement of linoleic acid is only usable in specific cases. These findings provide important consideration for the study of fungi growing in solid substrates and suggest that the use of PLFA might bias diversity indices.


Assuntos
Ergosterol/análise , Fungos/química , Fungos/crescimento & desenvolvimento , Técnicas Microbiológicas/métodos , Fosfolipídeos/análise , Caules de Planta/microbiologia , Triticum/microbiologia , Ácido Linoleico/análise , Phanerochaete , Schizophyllum
16.
Antonie Van Leeuwenhoek ; 111(5): 691-704, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29350358

RESUMO

The necrotrophic fungus Heterobasidion spp. is the causal agent of 'annosum root rot' of Norway spruce. In the presence of the rhizosphere bacterium Streptomyces AcH 505, enhanced colonization of Norway spruce roots with Heterobasidion abietinum 331 has previously been observed. By analyzing dual cultures of H. abietinum 331 and Streptomyces AcH 505 with HPLC, a fungal metabolite was identified that was increased in the presence of Streptomyces AcH 505. Likewise, challenge of H. abietum 331 with common antifungals produced by soil streptomycetes rendered the same effect. The structure of the compound, 5-formylsalicylic acid (5-FSA), was elucidated by HPLC-HR-ESI-Orbitrap-mass spectrometry and NMR spectroscopy. Based on in vivo measurements of maximum photosystem II efficiency of Norway spruce seedlings, 5-FSA did not influence plant vitality. However, when challenged with H. abietinum 331, ergosterol amounts in infected roots increased significantly for 5-FSA pre-treated seedlings. The severity of the infection was comparable to that observed in the presence of Streptomyces AcH 505. 5-FSA is a structural analogue of salicylic acid, an important signalling molecule active in plant defence. Thus, the expression of two defence-response related marker genes (PR1, Hel) was analysed in 5-FSA treated Arabidopsis thaliana seedlings by Northern blot analysis. The transcription of both marker genes was altered, indicating that 5-FSA is perceived by Arabidopsis in a similar manner to salicylic acid and is able to interfere with Arabidopsis defence signalling. The role of 5-FSA as a potential virulence factor of H. abietinum 331 in the presence of Streptomyces AcH 505 is discussed.


Assuntos
Basidiomycota/metabolismo , Picea , Doenças das Plantas/microbiologia , Salicilatos/metabolismo , Ácido Salicílico/metabolismo , Plântula/microbiologia , Streptomyces/metabolismo , Antifúngicos/metabolismo , Proteínas de Arabidopsis/genética , Basidiomycota/patogenicidade , Biotransformação , Técnicas de Cocultura , Ergosterol/análise , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Interações Microbianas , Proteínas de Plantas/genética , Salicilatos/química , Salicilatos/farmacologia , Transdução de Sinais/efeitos dos fármacos
17.
J Occup Environ Hyg ; 15(3): 182-193, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29157144

RESUMO

Dairy workers experience a high degree of bioaerosol exposure, composed of an array of biological and chemical constituents, which have been tied to adverse health effects. A better understanding of the variation in the magnitude and composition of exposures by task is needed to inform worker protection strategies. To characterize the levels and types of exposures, 115 dairy workers grouped into three task categories on nine farms in the high plains Western United States underwent personal monitoring for inhalable dust, endotoxin, 3-hydroxy fatty acids (3-OHFA), muramic acid, ergosterol, and ammonia through one work shift. Eighty-nine percent of dairy workers were exposed to endotoxin at concentrations exceeding the recommended exposure guidelines (adjusted for a long work shift). The proportion of workers with exposures exceeding recommended guidelines was lower for inhalable dust (12%), and ammonia (1%). Ergosterol exposures were only measurable on 28% of samples, primarily among medical workers and feed handlers. Milking parlor workers were exposed to significantly higher inhalable dust, endotoxin, 3-OHFA, ammonia, and muramic acid concentrations compared to workers performing other tasks. Development of large modern dairies has successfully made progress in reducing worker exposures and lung disease prevalence. However, exposure to endotoxin, dust, and ammonia continues to present a significant risk to worker health on North American dairies, especially for workers in milking parlors. This study was among the first to concurrently evaluate occupational exposure to assayable endotoxin (lipid A), 3-hydroxy fatty acids or 3-OHFA (a chemical measure of cell bound and noncell-bound endotoxins), muramic acid, ergosterol, and ammonia among workers on Western U.S. dairies. There remains a need for cost-effective, culturally acceptable intervention strategies integrated in OHS Risk Management and production systems to further optimize worker health and farm productivity.


Assuntos
Poluentes Ocupacionais do Ar/análise , Indústria de Laticínios , Exposição Ocupacional/análise , Adolescente , Adulto , Idoso , Amônia/análise , Colorado/epidemiologia , Poeira/análise , Endotoxinas/análise , Ergosterol/análise , Ácidos Graxos/análise , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ácidos Murâmicos/análise , Material Particulado/análise , Wyoming/epidemiologia
18.
Environ Sci Pollut Res Int ; 25(3): 2932-2941, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29147983

RESUMO

Paddy soil experiences repeated anaerobic and aerobic changes during rice growth, the dramatic dynamics of soil water status accompanied by changes in redox condition and O2 availability. However, the effect of rapid water status change on soil microbial biomass and community composition is not well explored. Here, we present a comprehensive study focusing on the short-term water status change in 13 Chinese paddy soils. In order to gain a reliable way to determine soil microbial biomass carbon (MBC) in flooded or water-saturated soils, we also evaluated two different procedures (nitrogen bubbled and 100 °C water bath) to remove chloroform in extracts during the fumigation process. Compared to non-flooded paddy soils, the flooded paddy soils tended to have a lower microbial biomass, and this was much clearer using adenosine 5'-triphosphate (ATP) and phospholipid fatty acid (PLFA) analysis compared to biomass measured by the fumigation method. Fungal biomass, which was indicated by both ergosterol and the PLFA 18:2ω6,9c, also decreased after short-term flooding. Changes in soil microbial community composition (determined by PLFA biomarkers) were observed after short-term flooding, but the extent varied between soils. This study indicates that the dynamics of short-term water status altered the soil microbial biomass (ATP, MBC, and total PLFA) and community composition. Finally, our results suggested that liquid fumigation combined with the nitrogen-bubbled method is the best choice for analyzing MBC concentrations in water-saturated soils.


Assuntos
Oryza/crescimento & desenvolvimento , Microbiologia do Solo , Solo/química , Água/análise , Bactérias/crescimento & desenvolvimento , Biomassa , China , Ergosterol/análise , Ácidos Graxos/análise , Fungos/crescimento & desenvolvimento , Consórcios Microbianos
19.
Sci Rep ; 7(1): 16942, 2017 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-29209074

RESUMO

The antifungal activities of heteropolytungstates, α-1,2,3-K6H[SiW9V3O40] (SiW-3), K13[Ce(SiW11O39)2]·17H2O (SiW-5), K13[Eu(SiW11O39)2]·25H2O (SiW-10), K6PV3W9O40 (PW-6), α-K4PVW11O40 (PW-8), were screened in 29 Candida albicans, 8 Candida glabrata, 3 Candida krusei, 2 Candida parapsilosis, 1 Candida tropicalis, and 1 Cryptococcus neoformans strains using the CLSI M27-A3 method. SiW-5 had the highest efficacy with a minimum inhibitory concentration (MIC) values of <0.2-10.2 µM in vitro. The antifungal mechanism, acute toxicity and in vivo antifungal activity of SiW-5 were then evaluated in C. albicans. The results showed that SiW-5 damaged the fungal cell membrane, reduce the ergosterol content and its main mode of action was through inhibition of ergosterol biosynthesis. Real-time PCR showed that ERG1, ERG7, ERG11 and ERG28 were all significantly upregulated by SiW-5. An acute toxicity study showed the 50% lethal dose (LD50) of SiW-5 for ICR mice was 1651.5 mg/kg. And in vivo antifungal studies demonstrated that SiW-5 reduced both the morbidity and fungal burden of mice infected with C. albicans. This study demonstrates that SiW-5 is a potential antifungal candidate against the Candida species.


Assuntos
Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Compostos de Tungstênio/química , Compostos de Tungstênio/farmacologia , Animais , Antifúngicos/efeitos adversos , Antifúngicos/química , Candida/genética , Candida/metabolismo , Candida albicans/efeitos dos fármacos , Candida albicans/patogenicidade , Candida albicans/ultraestrutura , Candidíase/tratamento farmacológico , Cromatografia Líquida de Alta Pressão , Avaliação Pré-Clínica de Medicamentos , Ergosterol/análise , Ergosterol/biossíntese , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos ICR , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Transmissão , Reação em Cadeia da Polimerase em Tempo Real , Testes de Toxicidade Aguda
20.
Int J Med Mushrooms ; 19(10): 925-935, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29256846

RESUMO

The incidence of vitamin D deficiency has increased in recent years, mainly in Europe. The consumption of processed mushrooms may play an important role in preventing diseases associated with vitamin D deficiency. We determined the effects of 2 kinds of freezing (blast, cryogenic), canning (mild and strong brine), and drying (air-drying, freeze-drying) on the retention of vitamin D2 and ergosterol in Agaricus bisporus. Fresh and processed A. bisporus mushrooms can be a good dietary source of vitamin D2. After 12 months of storage, canned mushrooms retained the largest amount of vitamin D2 and ergosterol, whereas the smallest amount was retained in dried mushrooms. Cryogenic freezing resulted in higher levels of vitamin D2, whereas ergosterol levels were higher using air-blast freezing. The drying method had a significant effect only on ergosterol levels, which were higher in the case of freeze-drying. Room temperature gave the best results for storing dried mushrooms. In canned mushrooms, the type of brine had an effect only on levels of vitamin D2; retention was higher using the strong brine. Retention of vitamin D2 was higher at cool temperatures, whereas room temperature resulted in higher retention of ergosterol in the canned products.


Assuntos
Agaricus/química , Ergocalciferóis/análise , Análise de Alimentos , Armazenamento de Alimentos/métodos , Cromatografia Líquida de Alta Pressão , Dessecação , Ergosterol/análise , Qualidade dos Alimentos , Congelamento , Humanos , Temperatura
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