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1.
PLoS One ; 16(10): e0255502, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34714855

RESUMO

We evaluated phytochemical composition, antibacterial, antifungal, anti-oxidant and cytotoxic properties of aqueous (water) and organic extracts (methanol, ethyl acetate and n-hexane) of Chenopodium glaucum. Highest phenolic content 45 mg gallic acid equivalents (GAE)/g d.w was found in aqueous extract followed by ethyl acetate (41mg GAE/g d.w) and methanol extract (34.46 mg GAE/g d.w). Antibacterial potential of aqueous and organic extracts of C. glaucum was examined against Acinetobacter baumannii, Klebsiella pneumoniae, Escherichia coli and Staphylococcus epidermidis. The aqueous, methanolic, ethyl acetate, and n-hexane extract showed antibacterial activity against A. baumannii, K. pneumoniae, E. coli and S. epidermidis. However, against A. baumannii significantly higher inhibition zone (19 mm and 18.96 mm respectively) was shown by ethyl acetate and methanol extracts. Aqueous extract possessed highest growth inhibition (11 mm) against E. coli. Aqueous, ethyl acetate and methanol extracts showed 9 mm, 10 mm, and 10.33 mm zone of inhibition against the K. pneumoniae. For antifungal activity, the extracts were less effective against Aspergillus niger but showed strong antifungal activity against Aspergillus flavus (A. flavus). The antioxidant activity was measured as DPPH (2, 2-diphenyl-1-picrylhydrazyl), H2O2 and ABTS (2, 2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) scavenging activity of free radicals. All the organic extracts of C. glaucum possessed ABTS, DPPH and H2O2 scavenging properties. The highest cytotoxic activity measured as half maximal inhibitory concentration (IC50) against human lungs carcinoma cells was recorded for methanolic (IC50 = 16 µg/mL) and n-hexane (IC50 = 25 µg/mL) extracts, respectively. The Gas chromatography-mass spectrometry (GC-MS) analysis showed 4 major and 26 minor compounds in n-hexane extract and 4 major and 7 minor compounds in methanol extract of the C. glaucum. It is concluded that aqueous and organic extracts of C. glaucum would be potential therapeutic agents and could be exploited on a pilot scale to treat human pathogenic diseases.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Antineoplásicos/farmacologia , Chenopodium/química , Neoplasias Pulmonares/tratamento farmacológico , Extratos Vegetais/farmacologia , Acinetobacter baumannii/efeitos dos fármacos , Acinetobacter baumannii/crescimento & desenvolvimento , Antioxidantes/farmacologia , Aspergillus/efeitos dos fármacos , Aspergillus/crescimento & desenvolvimento , Linhagem Celular Tumoral , Citotoxinas/farmacologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Humanos , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Compostos Fitoquímicos/farmacologia , Staphylococcus epidermidis/efeitos dos fármacos , Staphylococcus epidermidis/crescimento & desenvolvimento
2.
Molecules ; 26(11)2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34199488

RESUMO

In December 2020, the U.K. authorities reported to the World Health Organization (WHO) that a new COVID-19 variant, considered to be a variant under investigation from December 2020 (VUI-202012/01), was identified through viral genomic sequencing. Although several other mutants were previously reported, VUI-202012/01 proved to be about 70% more transmissible. Hence, the usefulness and effectiveness of the newly U.S. Food and Drug Administration (FDA)-approved COVID-19 vaccines against these new variants are doubtfully questioned. As a result of these unexpected mutants from COVID-19 and due to lack of time, much research interest is directed toward assessing secondary metabolites as potential candidates for developing lead pharmaceuticals. In this study, a marine-derived fungus Aspergillus terreus was investigated, affording two butenolide derivatives, butyrolactones I (1) and III (2), a meroterpenoid, terretonin (3), and 4-hydroxy-3-(3-methylbut-2-enyl)benzaldehyde (4). Chemical structures were unambiguously determined based on mass spectrometry and extensive 1D/2D NMR analyses experiments. Compounds (1-4) were assessed for their in vitro anti-inflammatory, antiallergic, and in silico COVID-19 main protease (Mpro) and elastase inhibitory activities. Among the tested compounds, only 1 revealed significant activities comparable to or even more potent than respective standard drugs, which makes butyrolactone I (1) a potential lead entity for developing a new remedy to treat and/or control the currently devastating and deadly effects of COVID-19 pandemic and elastase-related inflammatory complications.


Assuntos
4-Butirolactona/análogos & derivados , Antialérgicos/química , Anti-Inflamatórios/química , Aspergillus/química , SARS-CoV-2/enzimologia , Proteínas da Matriz Viral/antagonistas & inibidores , 4-Butirolactona/química , 4-Butirolactona/isolamento & purificação , 4-Butirolactona/metabolismo , Antialérgicos/metabolismo , Anti-Inflamatórios/metabolismo , Aspergillus/crescimento & desenvolvimento , Aspergillus/metabolismo , Sítios de Ligação , COVID-19/patologia , COVID-19/virologia , Domínio Catalítico , Humanos , Elastase de Leucócito/antagonistas & inibidores , Elastase de Leucócito/metabolismo , Espectroscopia de Ressonância Magnética , Conformação Molecular , Simulação de Acoplamento Molecular , Neutrófilos/enzimologia , SARS-CoV-2/isolamento & purificação , Água do Mar/microbiologia , Proteínas da Matriz Viral/metabolismo
3.
Sci Rep ; 11(1): 9347, 2021 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-33931710

RESUMO

A deep-sea fungus Aspergillus sydowii BOBA1 isolated from marine sediment at a depth of 3000 m was capable of degrading spent engine (SE) oil. The response of immobilized fungi towards degradation at elevated pressure was studied in customized high pressure reactors without any deviation in simulating in situ deep-sea conditions. The growth rate of A. sydowii BOBA1 in 0.1 MPa was significantly different from the growth at 10 MPa pressure. The degradation percentage reached 71.2 and 82.5% at atmospheric and high pressure conditions, respectively, within a retention period of 21 days. The complete genome sequence of BOBA1 consists of 38,795,664 bp in size, comprises 2582 scaffolds with predicted total coding genes of 18,932. A total of 16,247 genes were assigned with known functions and many families found to have a potential role in PAHs and xenobiotic compound metabolism. Functional genes controlling the pathways of hydrocarbon and xenobiotics compound degrading enzymes such as dioxygenase, decarboxylase, hydrolase, reductase and peroxidase were identified. The spectroscopic and genomic analysis revealed the presence of combined catechol, gentisate and phthalic acid degradation pathway. These results of degradation and genomic studies evidenced that this deep-sea fungus could be employed to develop an eco-friendly mycoremediation technology to combat the oil polluted marine environment. This study expands our knowledge on piezophilic fungi and offer insight into possibilities about the fate of SE oil in deep-sea.


Assuntos
Aspergillus/genética , Aspergillus/metabolismo , Biodegradação Ambiental , Genoma Fúngico , Sedimentos Geológicos/microbiologia , Peroxidases/metabolismo , Petróleo/metabolismo , Aspergillus/crescimento & desenvolvimento , Petróleo/microbiologia , Hidrocarbonetos Policíclicos Aromáticos/metabolismo
4.
Toxins (Basel) ; 13(4)2021 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-33807312

RESUMO

Ochratoxin A (OTA) usually contaminates agricultural products such as grapes, oatmeal, coffee and spices. Light was reported as an effective strategy to control spoilage fungi and mycotoxins. This research investigated the effects of light with different wavelengths on the growth and the production of OTA in Aspergillus ochraceus and Aspergillus carbonarius. The results showed that the growth of both fungi were extremely inhibited by UV-B. Short-wavelength (blue, violet) significantly inhibited the production of OTA in both fungi, while the inhibitory effect of white was only demonstrated on A. ochraceus. These results were supported by the expression profiles of OTA biosynthetic genes of A. ochraceus and A. carbonarius. To clarify, the decrease in OTA production is induced by inhibition or degradation; therefore, the degradation of OTA under different wavelengths of light was tested. Under UV-B, the degradation rate of 10 µg/mL OTA standard pure-solution samples could reach 96.50% in 15 days, and the degradation effect of blue light was relatively weak. Furthermore, infection experiments of pears showed that the pathogenicity of both fungi was significantly decreased under UV-B radiation. Thus, these results suggested that light could be used as a potential target for strategies in the prevention and control of ochratoxigenic fungi.


Assuntos
Aspergillus ochraceus/efeitos da radiação , Aspergillus/efeitos dos fármacos , Frutas/microbiologia , Ocratoxinas/biossíntese , Pyrus/microbiologia , Raios Ultravioleta , Aspergillus/genética , Aspergillus/crescimento & desenvolvimento , Aspergillus/metabolismo , Aspergillus ochraceus/genética , Aspergillus ochraceus/crescimento & desenvolvimento , Aspergillus ochraceus/metabolismo , Microbiologia de Alimentos , Regulação Fúngica da Expressão Gênica , Fatores de Tempo
5.
mBio ; 12(2)2021 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-33727355

RESUMO

Tip-growing fungal cells maintain cell polarity at the apical regions and elongate by de novo synthesis of the cell wall. Cell polarity and tip growth rate affect mycelial morphology. However, it remains unclear how both features act cooperatively to determine cell shape. Here, we investigated this relationship by analyzing hyphal tip growth of filamentous fungi growing inside extremely narrow 1 µm-width channels of microfluidic devices. Since the channels are much narrower than the diameter of hyphae, any hypha growing through the channel must adapt its morphology. Live-cell imaging analyses revealed that hyphae of some species continued growing through the channels, whereas hyphae of other species often ceased growing when passing through the channels, or had lost apical polarity after emerging from the other end of the channel. Fluorescence live-cell imaging analyses of the Spitzenkörper, a collection of secretory vesicles and polarity-related proteins at the hyphal tip, in Neurospora crassa indicates that hyphal tip growth requires a very delicate balance of ordered exocytosis to maintain polarity in spatially confined environments. We analyzed the mycelial growth of seven fungal species from different lineages, including phytopathogenic fungi. This comparative approach revealed that the growth defects induced by the channels were not correlated with their taxonomic classification or with the width of hyphae, but, rather, correlated with the hyphal elongation rate. This report indicates a trade-off between morphological plasticity and velocity in mycelial growth and serves to help understand fungal invasive growth into substrates or plant/animal cells, with direct impact on fungal biotechnology, ecology, and pathogenicity.IMPORTANCE Cell morphology, which is controlled by polarity and growth, is fundamental for all cellular functions. However how polarity and growth act cooperatively to control cell shape remains unclear. Here we investigated their relationship by analyzing hyphal tip growth of filamentous fungi growing inside extremely narrow 1 µm-width channels of microfluidic devices. We found that most fast growing hyphae often lost the cell polarity after emerging from the channels, whereas slow growing hyphae retained polarity and continued growing, indicating a trade-off between plasticity and velocity in mycelial growth. These results serve to understand fungal invasive growth into substrates or plant/animal cells, with direct impact on fungal biotechnology, ecology and pathogenicity.


Assuntos
Polaridade Celular , Fungos/crescimento & desenvolvimento , Hifas/citologia , Hifas/crescimento & desenvolvimento , Aspergillus/crescimento & desenvolvimento , Aspergillus/metabolismo , Citoplasma/metabolismo , Proteínas Fúngicas/metabolismo , Fungos/metabolismo , Microtúbulos , Neurospora crassa/crescimento & desenvolvimento , Neurospora crassa/metabolismo , Vesículas Secretórias/metabolismo
6.
J Microbiol ; 59(6): 563-572, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33779956

RESUMO

Fungi of the genus Aspergillus are ubiquitously distributed in nature, and some cause invasive aspergillosis (IA) infections in immunosuppressed individuals and contamination in agricultural products. Because microscopic observation and molecular detection of Aspergillus species represent the most operator-dependent and time-intensive activities, automated and cost-effective approaches are needed. To address this challenge, a deep convolutional neural network (CNN) was used to investigate the ability to classify various Aspergillus species. Using a dissecting microscopy (DM)/stereomicroscopy platform, colonies on plates were scanned with a 35× objective, generating images of sufficient resolution for classification. A total of 8,995 original colony images from seven Aspergillus species cultured in enrichment medium were gathered and autocut to generate 17,142 image crops as training and test datasets containing the typical representative morphology of conidiophores or colonies of each strain. Encouragingly, the Xception model exhibited a classification accuracy of 99.8% on the training image set. After training, our CNN model achieved a classification accuracy of 99.7% on the test image set. Based on the Xception performance during training and testing, this classification algorithm was further applied to recognize and validate a new set of raw images of these strains, showing a detection accuracy of 98.2%. Thus, our study demonstrated a novel concept for an artificial-intelligence-based and cost-effective detection methodology for Aspergillus organisms, which also has the potential to improve the public's understanding of the fungal kingdom.


Assuntos
Aspergilose/microbiologia , Aspergillus/química , Microscopia/métodos , Técnicas de Tipagem Micológica/métodos , Redes Neurais de Computação , Aspergillus/crescimento & desenvolvimento , Aspergillus/isolamento & purificação , Humanos , Técnicas de Tipagem Micológica/instrumentação
7.
Int J Food Microbiol ; 344: 109111, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33676331

RESUMO

Currants are prone to contamination by ochratoxin during cultivation, processing and storage conditions. Saccharomyces cerevisiae is considered to be among the main species of grape yeast flora able to control antagonistic fungi. In this study, the potential of S. cerevisiae Y33 was investigated to inhibit the growth of several fungal species indigenous to the microbiota of grapes. Moreover, the efficacy of this yeast species was investigated to inhibit OTA by toxin producing fungi both in vitro and in situ. For this purpose thirty-five different fungal species, belonging to the genera Aspergillus, Penicillium, Cladosporium, Fusarium and Alternaria interacted in vitro with S. cerevisiae on Malt Extract agar plates, stored at 25 °C for 14 days. Results showed that the highest OTA producer A. carbonarius F71 was inhibited more than 99% from day 7, in contrast to A. niger strains that presented enhanced OTA production at day 14 due to interaction with S. cerevisiae Y33. Additionally, the antifungal potential of the selected yeast was also studied in situ on currants subjected to different treatments and stored at 25 °C for 28 days. Microbiological analysis was undertaken for the enumeration of the bacterial and fungal flora, together with OTA determination at 7 and 21 days. To quantify A. carbonarius on all treated currant samples, molecular analysis with Real Time PCR was employed. A standard curve was prepared with A. carbonarius DNA. The efficiency of the curve was estimated to 10.416, the slope to -3.312 and the range of haploid genome that could be estimated was from 1.05 to 105∙105. The amount of A. carbonarius DNA in all treated currants samples, where the fungus was positively detected, ranged from as low as 0.08 to 562 ng DNA/g currants. The antifungal activity of S. cerevisiae Y33 was observed in all studied cases, causing inhibition of fungal growth and OTA production.


Assuntos
Antibiose/fisiologia , Ocratoxinas/biossíntese , Ribes/microbiologia , Saccharomyces cerevisiae/patogenicidade , Alternaria/crescimento & desenvolvimento , Alternaria/metabolismo , Antifúngicos/metabolismo , Aspergillus/crescimento & desenvolvimento , Aspergillus/metabolismo , Cladosporium/crescimento & desenvolvimento , Cladosporium/metabolismo , Frutas/microbiologia , Fusarium/crescimento & desenvolvimento , Fusarium/metabolismo , Penicillium/crescimento & desenvolvimento , Penicillium/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Saccharomyces cerevisiae/genética , Fermento Seco
8.
Food Microbiol ; 97: 103740, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33653519

RESUMO

Parameters such as type and concentration of the active compound, exposure time, application temperature, and organic load presence influence the antimicrobial action of sanitizers, although there is little data in the literature. Thus, this study aimed to evaluate the antifungal efficacy of different chemical sanitizers under different conditions according to the European Committee for Standardization (CEN). Aspergillus brasiliensis (ATCC 16404) was exposed to four compounds (benzalkonium chloride, iodine, peracetic acid, and sodium hypochlorite) at two different concentrations (minimum and maximum described on the product label), different exposure times (5, 10, and 15 min), temperatures (10, 20, 30, and 40 °C), and the presence or absence of an organic load. All parameters, including the type of sanitizer, influenced the antifungal efficacy of the tested compounds. Peracetic acid and benzalkonium chloride were the best antifungal sanitizers. The efficacy of peracetic acid increased as temperatures rose, although the opposite effect was observed for benzalkonium chloride. Sodium hypochlorite was ineffective under all tested conditions. In general, 5 min of sanitizer exposure is not enough and >10 min are necessary for effective fungal inactivation. The presence of organic load reduced sanitizer efficacy in most of the tested situations, and when comparing the efficacy of each compound in the presence and absence of an organic load, a difference of up to 1.5 log CFU was observed. The lowest concentration recommended on the sanitizer label is ineffective for 99.9% fungal inactivation, even at the highest exposure time (15 min) or under the best conditions of temperature and organic load absence. Knowledge of the influence exerted by these parameters contributes to successful hygiene since the person responsible for the sanitization process in the food facility can select and apply a certain compound in the most favorable conditions for maximum antifungal efficacy.


Assuntos
Antifúngicos/farmacologia , Aspergillus/efeitos dos fármacos , Compostos de Benzalcônio/farmacologia , Desinfetantes/farmacologia , Ácido Peracético/farmacologia , Hipoclorito de Sódio/farmacologia , Aspergillus/crescimento & desenvolvimento , Compostos de Benzalcônio/química , Contagem de Colônia Microbiana , Desinfetantes/análise , Ácido Peracético/análise , Hipoclorito de Sódio/análise , Temperatura , Fatores de Tempo
9.
Toxins (Basel) ; 13(2)2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33540740

RESUMO

Aspergillus carbonarius is the principal fungal species responsible for ochratoxin A (OTA) contamination of grapes and derived products in the main viticultural regions worldwide. In recent years, co-expressed genes representing a putative-OTA gene cluster were identified, and the deletion of a few of them allowed the partial elucidation of the biosynthetic pathway in the fungus. In the putative OTA-gene cluster is additionally present a bZIP transcription factor (AcOTAbZIP), and with this work, A. carbonarius ΔAcOTAbZIP strains were generated to study its functional role. According to phylogenetic analysis, the gene is conserved in the OTA-producing fungi. A Saccharomyces cerevisiae transcription factor binding motif (TFBM) homolog, associated with bZIP transcription factors was present in the A. carbonarius OTA-gene cluster no-coding regions. AcOTAbZIP deletion results in the loss of OTA and the intermediates OTB and OTß. Additionally, in ΔAcOTAbZIP strains, a down-regulation of AcOTApks, AcOTAnrps, AcOTAp450, and AcOTAhal genes was observed compared to wild type (WT). These results provide evidence of the direct involvement of the AcOTAbZIP gene in the OTA biosynthetic pathway by regulating the involved genes. The loss of OTA biosynthesis ability does not affect fungal development as demonstrated by the comparison of ΔAcOTAbZIP strains and WT strains in terms of vegetative growth and asexual sporulation on three different media. Finally, no statistically significant differences in virulence were observed among ΔAcOTAbZIP strains and WT strains on artificially inoculated grape berries, demonstrating that OTA is not required by A. carbonarius for the pathogenicity process.


Assuntos
Aspergillus/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Ocratoxinas/biossíntese , Aspergillus/genética , Aspergillus/crescimento & desenvolvimento , Aspergillus/patogenicidade , Fatores de Transcrição de Zíper de Leucina Básica/genética , Frutas/microbiologia , Deleção de Genes , Regulação Fúngica da Expressão Gênica , Família Multigênica , Mutação , Reprodução Assexuada , Metabolismo Secundário , Fatores de Tempo , Virulência , Vitis/microbiologia
10.
Microb Cell Fact ; 20(1): 42, 2021 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-33579268

RESUMO

BACKGROUND: The co-culture strategy which mimics natural ecology by constructing an artificial microbial community is a useful tool to activate the biosynthetic gene clusters to generate new metabolites. However, the conventional method to study the co-culture is to isolate and purify compounds separated by HPLC, which is inefficient and time-consuming. Furthermore, the overall changes in the metabolite profile cannot be well characterized. RESULTS: A new approach which integrates computational programs, MS-DIAL, MS-FINDER and web-based tools including GNPS and MetaboAnalyst, was developed to analyze and identify the metabolites of the co-culture of Aspergillus sydowii and Bacillus subtilis. A total of 25 newly biosynthesized metabolites were detected only in co-culture. The structures of the newly synthesized metabolites were elucidated, four of which were identified as novel compounds by the new approach. The accuracy of the new approach was confirmed by purification and NMR data analysis of 7 newly biosynthesized metabolites. The bioassay of newly synthesized metabolites showed that four of the compounds exhibited different degrees of PTP1b inhibitory activity, and compound N2 had the strongest inhibition activity with an IC50 value of 7.967 µM. CONCLUSIONS: Co-culture led to global changes of the metabolite profile and is an effective way to induce the biosynthesis of novel natural products. The new approach in this study is one of the effective and relatively accurate methods to characterize the changes of metabolite profiles and to identify novel compounds in co-culture systems.


Assuntos
Aspergillus/crescimento & desenvolvimento , Bacillus subtilis/crescimento & desenvolvimento , Metabolismo Secundário , Técnicas de Cocultura
11.
Fungal Biol ; 125(2): 115-122, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33518201

RESUMO

Little is known on the impact that climate change (CC) may have on Aspergillus carbonarius and Ochratoxin A (OTA) contamination of grapes, especially in the Mediterranean region where in CC scenarios temperature are expected to increase by +2-5 °C and CO2 from 400 to 800/1200 ppm. This study examined the effect of (i) current and increased temperature in the alternating 11.5 h dark/12.5 h light cycle (15-28 °C vs 18-34 °C), representative of the North Apulia area, South Italy and (ii) existing and predicted CO2 concentrations (400 vs 1000 ppm), on growth, expression of biosynthetic genes (AcOTApks, AcOTAnrps, AcOTAhal, AcOTAp450, AcOTAbZIP) and regulatory genes of Velvet complex (laeA/veA/velB, "velvet complex") involved in OTA biosynthesis and OTA phenotypic production by three strains of A. carbonarius. The experiments made on a grape-based matrix showed that elevated CO2 resulted in a general stimulation of growth and OTA production. These results were also supported by the up-regulation of both structural and regulatory genes involved in the OTA biosynthesis. Our work has shown for the first time that elevated CO2 concentration in the Mediterranean region may result in an increased risk of OTA contamination in the wine production chain.


Assuntos
Aspergillus , Mudança Climática , Expressão Gênica , Ocratoxinas , Vitis , Aspergillus/genética , Aspergillus/crescimento & desenvolvimento , Aspergillus/metabolismo , Dióxido de Carbono , Itália , Ocratoxinas/metabolismo , Temperatura , Vitis/química
12.
Bioorg Chem ; 107: 104623, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33444984

RESUMO

Three new alkaloids (1-3) together with four previously reported compounds (4-7) were identified from the extracts and the diversity-enhanced extracts of the fermentation broth of the endophytic fungus, Aspergillus flavus GZWMJZ-288 associated with Garcinia multiflora. The structures of new compounds were respectively determined as 19-amino-19-dehydroxy 5-epi-α-cyclopiazonic acid (1), 2-hydroxymethyl-5-(3-oxobutan-2-yl)aminopyran-4(4H)-one (2) and 4-amino-2-hydroxymethylpyridin-5-ol (3) by spectroscopic analysis, ECD calculation and X-ray single crystal diffraction. Compounds 1 and 4 with 19-enamine were dynamic equilibrium of Z- and E- isomers in the solution but favored in Z- isomers in the solid state, while compound 7 with 19-enol was favored in Z- isomer in the solution but a mixture of Z- and E- isomers in solid state. This phenomenon could be explained by the quantum-mechanical energies calculations. Among the isolated compounds 1-7, compounds 1, 4 and 7 with a rare 1,3,4,5-tetrahydro-1-azaacenaphtho[3,4-c]pyrrolizidine skeleton showed α-glucosidase inhibitory activity with the IC50 values of 41.97 ± 0.97, 232.57 ± 11.45 and 243.95 ± 3.36 µM, respectively, and the binding modes were performed by silico docking studies.


Assuntos
Alcaloides/química , Aspergillus/química , Alcaloides/isolamento & purificação , Alcaloides/metabolismo , Aspergillus/crescimento & desenvolvimento , Aspergillus/metabolismo , Sítios de Ligação , Cristalografia por Raios X , Garcinia/microbiologia , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Inibidores de Glicosídeo Hidrolases/metabolismo , Humanos , Espectroscopia de Ressonância Magnética , Conformação Molecular , Simulação de Acoplamento Molecular , Estrutura Terciária de Proteína , Teoria Quântica , Estereoisomerismo , alfa-Glucosidases/química , alfa-Glucosidases/metabolismo
13.
J Sci Food Agric ; 101(6): 2414-2421, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33012097

RESUMO

BACKGROUND: Aspergillus carbonarius has been identified as one of the main fungi that produce ochratoxin A (OTA) in grapes. This nephrotoxic mycotoxin has been legislated against in several countries and is a major concern for viticulture. Knowledge of resistance to, or susceptibility to, colonization by A. carbonarius may be useful in selecting the most promising cultivars for organic agriculture and could help in preventing fungal contamination in vineyards. This study aimed to evaluate the colonization potential and the capacity to produce OTA by A. carbonarius in Vitis vinifera, V. labrusca, and hybrid grapes. The correlation between OTA levels and grape berry characteristics was also analyzed. RESULTS: The OTA content was only strongly correlated with the thickness and hardness of the grape skins. The correlation between OTA levels and these parameters was negative (grapes with the least thickness and hardness had the highest OTA levels). Vitis vinifera grapes were more susceptible to A. carbonarius than V. labrusca and hybrid grapes at both 25 and 4 °C. Chardonnay (V. vinifera) grapes showed the highest levels of OTA, followed by Merlot, Cabernet Sauvignon, Tannat, and Moscato Branco. Italia grapes were the exceptions among V. vinifera cultivars, since they showed similar thickness, hardness, and fungal resistance as the V. labrusca and hybrid grapes. CONCLUSION: The highest resistance to A. carbonarius was observed in the following grapes: hybrids (BRS Lorena and BRS Violeta), V. labrusca (Isabel and Bordo), and V. vinifera (Italia). These cultivars can be prioritized in the implementation of organic viticulture. © 2020 Society of Chemical Industry.


Assuntos
Aspergillus/crescimento & desenvolvimento , Frutas/química , Ocratoxinas/análise , Vitis/crescimento & desenvolvimento , Aspergillus/metabolismo , Resistência à Doença , Contaminação de Alimentos/análise , Frutas/classificação , Frutas/crescimento & desenvolvimento , Frutas/microbiologia , Ocratoxinas/metabolismo , Agricultura Orgânica , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Vitis/química , Vitis/classificação , Vitis/microbiologia
14.
Prep Biochem Biotechnol ; 51(8): 749-760, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33315537

RESUMO

Lipases are enzymes employed in several industrial process and their applicability can be increased if these biocatalysts are in the immobilize form. The objective of this work was to study the immobilization of lipase produced by submerged cultivation of Aspergillus sp. by hydrophobic interaction, evaluating its stability and reuse capacity. The immobilization process on octyl-sepharose (C8) and octadecyl-sepabeads (C18) carriers was possible after the removal of oil excess presented in the fermented broth. The results showed that the enzyme was isolated and concentrated in octyl-sepharose with 22% of the initial activity. To increase the amount of enzyme adsorbed on the carrier, 4 immobilization cycles were performed in a row, on the same carrier, with a final immobilization yield of 151.32% and an increase in the specific activity of 136%. The activity test with immobilized lipase showed that the immobilized enzyme maintained 75% of the initial activity after 20 cycles.


Assuntos
Aspergillus/enzimologia , Enzimas Imobilizadas/química , Proteínas Fúngicas/química , Lipase/química , Aspergillus/crescimento & desenvolvimento , Estabilidade Enzimática , Enzimas Imobilizadas/biossíntese , Proteínas Fúngicas/biossíntese , Lipase/biossíntese
15.
Pak J Biol Sci ; 23(11): 1473-1480, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33274877

RESUMO

BACKGROUND AND OBJECTIVE: In the rainy season farmers don't interest to cultivate shallot because in addition to providing a high dosage of fertilizer they are also sensitive to pathogenic attacks so they are afraid of crop failure and cause low shallot production. This study aimed to knew effect of agronomic component and quality of shallot under different concentrations of biofertilizer and Ammonium Sulphate (AS) fertilizer dose in the rainy season. MATERIALS AND METHODS: The study was conducted in Cangkring, Srandakan, Bantul, Special Region of Yogyakarta Indonesia from August to October 2019. The study was arranged in RCBD factorial with three replications. The first factor was a various dose of ammonium sulphate (100, 200 and 300 kg ha-1). The second factor was various concentrations of biofertilizer (2, 3 and 4%), and control. The observed variables were the analysis of growth yield and quality component of shallot plant. The analyzed using analysis of variance at 5% of significance then continued by DMRT at 5% of significance. RESULTS: There was the interaction between the application of AS dosage and biofertilizer concentration on all of variable observations. There was a significant difference between treatment with control on all of the observation variables. CONCLUSION: The combination of AS fertilizer 200 kg ha-1 dose and 3% biofertilizer concentration increased agronomic efficiency, growth, bulbs yields, and quality of bulbs include provitamin A, oleoresin compounds.


Assuntos
Sulfato de Amônio , Produtos Agrícolas/crescimento & desenvolvimento , Fertilizantes/microbiologia , Valor Nutritivo , Chuva , Estações do Ano , Cebolinha Branca/crescimento & desenvolvimento , Microbiologia do Solo , Aspergillus/crescimento & desenvolvimento , Azospirillum/crescimento & desenvolvimento , Produtos Agrícolas/metabolismo , Produtos Agrícolas/microbiologia , Indonésia , Extratos Vegetais/metabolismo , Provitaminas/metabolismo , Cebolinha Branca/metabolismo , Cebolinha Branca/microbiologia , Trichoderma/crescimento & desenvolvimento , Vitamina A/metabolismo
16.
Compr Rev Food Sci Food Saf ; 19(2): 643-669, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-33325175

RESUMO

In this review, we present the current information on development and applications of biological control against phytopathogenic organisms as well as mycotoxigenic fungi in Malaysia as part of the integrated pest management (IPM) programs in a collective effort to achieve food security. Although the biological control of phytopathogenic organisms of economically important crops is well established and widely practiced in Malaysia with considerable success, the same cannot be said for mycotoxigenic fungi. This is surprising because the year round hot and humid Malaysian tropical climate is very conducive for the colonization of mycotoxigenic fungi and the potential contamination with mycotoxins. This suggests that less focus has been made on the control of mycotoxigenic species in the genera Aspergillus, Fusarium, and Penicillium in Malaysia, despite the food security and health implications of exposure to the mycotoxins produced by these species. At present, there is limited research in Malaysia related to biological control of the key mycotoxins, especially aflatoxins, Fusarium-related mycotoxins, and ochratoxin A, in key food and feed chains. The expected threats of climate change, its impacts on both plant physiology and the proliferation of mycotoxigenic fungi, and the contamination of food and feed commodities with mycotoxins, including the discovery of masked mycotoxins, will pose significant new global challenges that will impact on mycotoxin management strategies in food and feed crops worldwide. Future research, especially in Malaysia, should urgently focus on these challenges to develop IPM strategies that include biological control for minimizing mycotoxins in economically important food and feed chains for the benefit of ensuring food safety and food security under climate change scenarios.


Assuntos
Contaminação de Alimentos/prevenção & controle , Fungos/crescimento & desenvolvimento , Micotoxinas , Doenças das Plantas/microbiologia , Aspergillus/crescimento & desenvolvimento , Agentes de Controle Biológico , Produtos Agrícolas/microbiologia , Inocuidade dos Alimentos , Fusarium/crescimento & desenvolvimento , Malásia , Penicillium/crescimento & desenvolvimento , Doenças das Plantas/prevenção & controle
17.
J Food Sci ; 85(11): 3920-3926, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33067797

RESUMO

The presence of mycotoxigenic fungi such as Aspergillus, Penicillium, and Fusarium genera represents a problem in food preservation and consequently, its spoilage. During the fermentation process with lactic acid bacteria, a range of secondary metabolites associated with beneficial health effects were released. In the present study, goat whey fermented by Lactobacillus plantarum (CECT 220, 221, 223, and 748) species has shown a satisfactory inhibitory effect against 28 fungi, showing for certain species of Fusarium genus and also, for Aspergillus steynii, a value of minimum inhibitory concentration until 1.95 g/L. In addition, phenyllactic acid was identified in each sample of fermented whey at a concentration ranged from 0.34 to 1.21 mg/L. These results suggest the possible use of fermented whey as a source of new preservatives of natural origin to incorporate in food matrices for the purpose of improving the shelf life. PRACTICAL APPLICATION: Whey could be a good candidate for use as a natural antifungal agent to incorporate in food matrices. Whey could be used to prevent specific fungal growth that naturally occurs in food preparations. Consequentially, whey could enhance the shelf life of edible products.


Assuntos
Antifúngicos/metabolismo , Antifúngicos/farmacologia , Lactobacillus plantarum/metabolismo , Soro do Leite/metabolismo , Animais , Aspergillus/efeitos dos fármacos , Aspergillus/crescimento & desenvolvimento , Fermentação , Fusarium/efeitos dos fármacos , Fusarium/crescimento & desenvolvimento , Cabras , Testes de Sensibilidade Microbiana , Penicillium/efeitos dos fármacos , Penicillium/crescimento & desenvolvimento , Soro do Leite/química , Soro do Leite/microbiologia , Proteínas do Soro do Leite/metabolismo , Proteínas do Soro do Leite/farmacologia
18.
J Agric Food Chem ; 68(45): 12719-12728, 2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-33124819

RESUMO

Conventional methods for detecting fungal contamination are generally time-consuming and sample-destructive, making them impossible for large-scale nondestructive detection and real-time analysis. Therefore, the potential of headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) was examined for the rapid determination of fungal infection on wheat samples in a rapid and nondestructive manner. In addition, the validation experiment of detecting the percent A. flavus infection presented in simulated field samples was carried out. Because the dual separation of HS-GC-IMS could generate massive amounts of three-dimensional data, proper chemometric processing was required. In this study, two chemometric strategies including: (i) nontargeted spectral fingerprinting and (ii) targeted specific markers were introduced to evaluate the performances of classification and prediction models. Results showed that satisfying results for the differentiation of fungal species were obtained based on both strategies (>80%) by the genetic algorithm optimized support vector machine (GA-SVM), and better values were obtained based on the first strategy (100%). Likewise, the GA-SVM model based on the first strategy achieved the best prediction performances (R2 = 0.979-0.998) of colony counts in fungal infected samples. The results of validation experiment showed that GA-SVM models based on the first strategy could still provide satisfactory classification (86.67%) and prediction (R2 = 0.889) performances for percent A. flavus infection presented in simulated field samples at day 4. This study indicated the feasibility of HS-GC-IMS-based approaches for the early detection of fungal contamination in wheat kernels.


Assuntos
Aspergillus/isolamento & purificação , Contaminação de Alimentos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Penicillium/isolamento & purificação , Triticum/microbiologia , Aspergillus/crescimento & desenvolvimento , Penicillium/crescimento & desenvolvimento , Triticum/química
19.
Molecules ; 25(19)2020 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-32987627

RESUMO

The aim of this project was to improve the Aspergillus terreus strain and pretreatment of sugarcane bagasse as carrier substrate for bulk production of lovastatin, a cholesterol-lowering drug, in solid state fermentation. Sugarcane bagasse was treated with alkali (1-3% NaOH) for the conversion of complex polysaccharides into simple sugars for better utilization of carrier substrate by microorganism for maximum lovastatin production. Ethidium bromide (time of exposure 30-180 min) was used to induce mutation in Aspergillus terreus and the best mutant was selected on the basis of inhibition zone appeared on petri plates. Fermented lovastatin was quantified by high-performance liquid chromatography. The fermented lovastatin, produced by parent and mutant Aspergillus terreus strain, was checked on body weight, blood glucose and serum cholesterol, ALT, AST, HDL-C, LDL-C, TG and TC levels of rats for their cholesterol lowering capacity. Our results indicate that selected strain along with 2% NaOH treated sugar cane bagasse was best suitable for bulk production of lovastatin by fermentation and fermented lovastatin effectively lower the cholesterol level of rats.


Assuntos
Anticolesterolemiantes , Aspergillus , Colesterol/sangue , Lovastatina , Animais , Anticolesterolemiantes/isolamento & purificação , Anticolesterolemiantes/farmacocinética , Anticolesterolemiantes/farmacologia , Aspergillus/genética , Aspergillus/crescimento & desenvolvimento , Celulose/química , Avaliação Pré-Clínica de Medicamentos , Lovastatina/biossíntese , Lovastatina/isolamento & purificação , Lovastatina/farmacocinética , Lovastatina/farmacologia , Masculino , Ratos , Saccharum/química
20.
Sci Rep ; 10(1): 14500, 2020 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-32879425

RESUMO

The impact of material chemical composition on microbial growth on building materials remains relatively poorly understood. We investigate the influence of the chemical composition of material extractives on microbial growth and community dynamics on 30 different wood species that were naturally inoculated, wetted, and held at high humidity for several weeks. Microbial growth was assessed by visual assessment and molecular sequencing. Unwetted material powders and microbial swab samples were analyzed using reverse phase liquid chromatography with tandem mass spectrometry. Different wood species demonstrated varying susceptibility to microbial growth after 3 weeks and visible coverage and fungal qPCR concentrations were correlated (R2 = 0.55). Aspergillaceae was most abundant across all samples; Meruliaceae was more prevalent on 8 materials with the highest visible microbial growth. A larger and more diverse set of compounds was detected from the wood shavings compared to the microbial swabs, indicating a complex and heterogeneous chemical composition within wood types. Several individual compounds putatively identified in wood samples showed statistically significant, near-monotonic associations with microbial growth, including C11H16O4, C18H34O4, and C6H15NO. A pilot experiment confirmed the inhibitory effects of dosing a sample of wood materials with varying concentrations of liquid C6H15NO (assuming it presented as Diethylethanolamine).


Assuntos
Materiais de Construção , Microbiologia Ambiental , Monitoramento Ambiental , Fungos/crescimento & desenvolvimento , Madeira/química , Aspergillus/crescimento & desenvolvimento , Aspergillus/isolamento & purificação , Basidiomycota/crescimento & desenvolvimento , Basidiomycota/isolamento & purificação , Cromatografia Líquida , Análise por Conglomerados , Fungos/isolamento & purificação , Umidade , Reação em Cadeia da Polimerase , Pós , RNA Ribossômico , Espectrometria de Massas em Tandem
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