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1.
Artigo em Inglês | MEDLINE | ID: mdl-35219088

RESUMO

Luliconazole (LCZ) is a novel antifungal imidazole with broad-spectrum and high susceptibility of Aspergillus and Fusarium are the dominant species of fungal keratitis, may potentially be a new medical treatment option for ocular fungal infection. To evaluate LCZ distribution in ocular tissues after topical application for the development of ophthalmic delivery system, it is important to have a bioanalytical method for measuring the drug concentrations in different ocular tissues and aqueous humor (AH). A selective and sensitive ultrahigh performance liquid chromatography coupled with tandem mass spectrometry (UPLC-MS/MS) method was developed for the quantification of LCZ in rabbit ocular tissues, including conjunctiva, cornea, AH, iris, lens, vitreous humor (VH), retinal choroid and sclera, using lanoconazole as internal standard (IS). Chromatographic separation was achieved on a Xterra MS, C18 column (2.1 × 50 mm, 3.5 µm) using mobile phase with formic acid solution (0.2%, v/v): acetonitrile (50:50, v/v) at a flow rate of 0.2 ml/min, and the run time was 2.5 min. Detection was performed using the transitions 354.1 → 150.3 m/z for LCZ and 320.1 → 150.3 m/z for IS by positive ion electrospray ionization in multiple reaction monitoring (MRM) mode. Method validation was conducted in accordance with U.S. Food and Drug Administration's regulatory guidelines for bioanalytical method validation. The calibration curves were linear over the concentration range from 2.80 ng/ml to 2038 ng/ml for conjunctiva, cornea and sclera, 2.09 ng/ml to 1019 ng/ml for AH, 2.09 ng/ml to 509.5 ng/ml for iris, 2.09 ng/ml to 203.8 ng/ml for retinal choroid and VH, 2.04 ng/ml to 101.9 ng/ml for lens, with all the squared correlation coefficients (r2) more than 0.99. The accuracy of the method was within the acceptable limit of 89.34%∼112.78% at the lower limit of quantification and other concentrations, Inter-day and intra-day precision values, expressed in terms of RSD (%), in all tissues were within 15% at all concentrations. The mean recoveries of LCZ in rabbit ocular tissues was 84.85%∼100.52%. No interference was found due to matrix components. Luliconazole was stable during the stability studies, including autosampler stability, benchtop stability, freeze/thaw stability and long-term stability. The method was successfully applied to the ocular pharmacokinetic and tissues distribution studies of LCZ in rabbit after topical administration of LCZ ophthalmic drug delivery system.


Assuntos
Antifúngicos/análise , Cromatografia Líquida de Alta Pressão/métodos , Oftalmopatias/tratamento farmacológico , Olho/química , Imidazóis/análise , Espectrometria de Massas em Tandem/métodos , Administração Tópica , Animais , Antifúngicos/administração & dosagem , Aspergillus/efeitos dos fármacos , Aspergillus/crescimento & desenvolvimento , Oftalmopatias/microbiologia , Fusarium/efeitos dos fármacos , Fusarium/crescimento & desenvolvimento , Humanos , Imidazóis/administração & dosagem , Coelhos , Sensibilidade e Especificidade
2.
BMC Plant Biol ; 22(1): 73, 2022 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-35183130

RESUMO

BACKGROUND: Chitosan has shown potential for the control of Fusarium head blight (FHB) disease caused by Fusarium graminearum. The objective of this study was to compare the effect of chitosan hydrochloride applied pre- or post-fungal inoculation on FHB and to better understand its' mode of action via an untargeted metabolomics study. RESULTS: Chitosan inhibited fungal growth in vitro and, when sprayed on the susceptible wheat cultivar Remus 24 hours pre-inoculation with F. graminearum, it significantly reduced the number of infected spikelets at 7, 14 and 21 days post-inoculation. Chitosan pre-treatment also increased the average grain weight per head, the number of grains per head and the 1000-grain weight compared to the controls sprayed with water. No significant impact of chitosan on grain yield was observed when the plants were sprayed 24 hours post-inoculation with F. graminearum, even if it did result in a reduced number of infected spikelets at every time point. An untargeted metabolomic study using UHPLC-QTOF-MS on wheat spikes revealed that spraying the spikes with both chitosan and F. graminearum activated known FHB resistance pathways (e.g. jasmonic acid). Additionally, more metabolites were up- or down-regulated when both chitosan and F. graminearum spores were sprayed on the spikes (117), as compared with chitosan (51) or F. graminearum on their own (32). This included a terpene, a terpenoid and a liminoid previously associated with FHB resistance. CONCLUSIONS: In this study we showed that chitosan hydrochloride inhibited the spore germination and hyphal development of F. graminearum in vitro, triggered wheat resistance against infection by F. graminearum when used as a pre-inoculant, and highlighted metabolites and pathways commonly and differentially affected by chitosan, the pathogen and both agents. This study provides insights into how chitosan might provide protection or stimulate wheat resistance to infection by F. graminearum. It also unveiled new putatively identified metabolites that had not been listed in previous FHB or chitosan-related metabolomic studies.


Assuntos
Quitosana/farmacologia , Fusarium/efeitos dos fármacos , Doenças das Plantas/microbiologia , Triticum/efeitos dos fármacos , Triticum/microbiologia , Cromatografia Líquida de Alta Pressão , Ciclopentanos/metabolismo , Fungicidas Industriais/farmacologia , Fusarium/crescimento & desenvolvimento , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Espectrometria de Massas , Metaboloma , Oxilipinas/metabolismo , Triticum/metabolismo
3.
Carbohydr Polym ; 282: 119111, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35123746

RESUMO

Novel bio-based nanocomposites were developed as carriers for loading and sustained-release of vanillin (Van.) and cinnamaldehyde (Cinn.) antioxidants. The composites were obtained by intercalation of chitosan (CS) into sodium montmorillonite (CS/Mt), incorporation of chitosan with polyaniline (CS/PANI) and chitosan/polyaniline/exfoliated montmorillonite (CS/PANI/Mt). The structure and morphology of composites were characterized by FTIR, XRD, SEM and TEM. The release data of Van. and Cinn. from CS and CS/Mt obeyed well zero-order equation. However, Higuchi and Korsmeyer-Peppas models fitted well the release data from CS/PANI and CS/Mt composites. Their antifungal activity was examined towards Fusarium oxysporum and Pythium debaryanum. In vitro assay, CS, Cinn., Van., CS/PANI and CS/PANI/Cinn., have a strong inhibitory effect on the linear growth of the target pathogens, even at lower concentrations. Greenhouse assay indicated that seedling treatment by the loaded CS/PANI/Cinn and CS/Mt/Cinn. reduced both disease index and disease incidence parameters of both pathogens and possessed seedlings growth promoting potential of tomato compared to untreated-infected controls.


Assuntos
Acroleína/análogos & derivados , Antioxidantes/administração & dosagem , Benzaldeídos/administração & dosagem , Agentes de Controle Biológico/administração & dosagem , Quitosana/administração & dosagem , Fusarium/efeitos dos fármacos , Nanocompostos/administração & dosagem , Doenças das Plantas/prevenção & controle , Pythium/efeitos dos fármacos , /microbiologia , Acroleína/administração & dosagem , Acroleína/química , Adsorção , Compostos de Anilina/administração & dosagem , Compostos de Anilina/química , Antioxidantes/química , Bentonita/administração & dosagem , Bentonita/química , Benzaldeídos/química , Agentes de Controle Biológico/química , Quitosana/química , Liberação Controlada de Fármacos , Fusarium/crescimento & desenvolvimento , Nanocompostos/química , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/microbiologia , Pythium/crescimento & desenvolvimento
4.
Toxins (Basel) ; 14(2)2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-35202169

RESUMO

Fusarium graminearum is a harmful pathogen causing head blight in cereals such as wheat and barley, and thymol has been proven to inhibit the growth of many pathogens. This study aims to explore the fungistatic effect of thymol on F. graminearum and its mechanism. Different concentrations of thymol were used to treat F. graminearum. The results showed that the EC50 concentration of thymol against F. graminearum was 40 µg/mL. Compared with the control group, 40 µg/mL of thymol reduced the production of Deoxynivalenol (DON) and 3-Ac-DON by 70.1% and 78.2%, respectively. Our results indicate that thymol can effectively inhibit the growth and toxin production of F. graminearum and cause an extensive transcriptome response. Transcriptome identified 16,727 non-redundant unigenes and 1653 unigenes that COG did not annotate. The correlation coefficients between samples were all >0.941. When FC was 2.0 times, a total of 3230 differential unigenes were identified, of which 1223 were up-regulated, and 2007 were down-regulated. Through the transcriptome, we confirmed that the expression of many genes involved in F. graminearum growth and synthesis of DON and other secondary metabolites were also changed. The gluconeogenesis/glycolysis pathway may be a potential and important way for thymol to affect the growth of F. graminearum hyphae and the production of DON simultaneously.


Assuntos
Antifúngicos/química , Fusarium/crescimento & desenvolvimento , Fusarium/metabolismo , Micélio/efeitos dos fármacos , Micélio/crescimento & desenvolvimento , Micotoxinas/biossíntese , Micotoxinas/química , Timol/química , Transcriptoma
5.
Plant Dis ; 106(1): 34-38, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34282928

RESUMO

Fusarium graminearum is an important fungus causing a variety of maize diseases, including stalk rot, ear rot, and sheath rot. However, conidia of F. graminearum are not easily obtained under normal culture conditions, which seriously affects the identification and pathogenicity assessment of the isolates and screening of resistance sources. This study was undertaken to develop and utilize a rapid sporulation technique of F. graminearum using liquid cultivation, which could meet the needs of various tests. The results show that the optimum conditions for sporulation of F. graminearum were as follows: culture medium, 0.154 mol/liter of saline; temperature, 28 to 30°C; incubation time, 96 h; initial pH, 9 to 10; illumination, continuous ultraviolet light; and shaking speed, 150 rpm. Using this culture method, conidial concentration of tested F. graminearum strains can reach >1.5 × 105 conidia/ml. Compared with the existing methods using mung bean and carboxylmethyl cellulose as matrix, saline is relatively inexpensive, and the culture process, relatively quick. Overall, this study provided a systematic, rapid, and simple method to obtain a large number of conidia of F. graminearum.


Assuntos
Fusarium , Técnicas Microbiológicas/métodos , Esporos Fúngicos , Fusarium/crescimento & desenvolvimento , Doenças das Plantas , Esporos Fúngicos/crescimento & desenvolvimento , Zea mays
6.
J Microbiol Methods ; 192: 106379, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34808145

RESUMO

This work addresses the mathematical model building to detect the diameter of the inhibition zone of gilaburu (Viburnum opulus L.) extract against eight different Fusarium strains isolated from diseased potato tubers. Gilaburu extracts were obtained with acetone, ethanol or methanol. The isolated Fusarium strains were: F. solani, F. oxysporum, F. sambucinum, F. graminearum, F. coeruleum, F. sulphureum, F. auneaceum and F. culmorum. In general, it was observed that ethanolic extracts showed highest antifungal activity. The antifungal activity of extracts was evaluated with machine learning (ML) methods. Several ML methods (classification and regression trees (CART), support vector machines (SVM), k-Nearest Neighbors (k-NN), artificial neural network (ANN), ensemble algorithms (EA), AdaBoost (AB) algorithm, gradient boosting (GBM) algorithm, random forests (RF) bagging algorithm and extra trees (ET)) were applied and compared for modeling fungal growth. From this research, it is clear that ML methods have the lowest error level. As a result, ML methods are reliable, fast, and cheap tools for predicting the antifungal activity of gilaburu extracts. These encouraging results will attract more research efforts to implement ML into the field of food microbiology instead of traditional methods.


Assuntos
Antifúngicos/farmacologia , Fusarium/crescimento & desenvolvimento , Aprendizado de Máquina , Extratos Vegetais/farmacologia , Solanum tuberosum/microbiologia , Viburnum/química , Algoritmos , Antioxidantes/farmacologia , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão/métodos , Microbiologia de Alimentos , Fusarium/efeitos dos fármacos , Fusarium/isolamento & purificação
7.
Elife ; 102021 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-34927582

RESUMO

Fusarium oxysporum is one of the most important pathogenic fungi with a broad range of plant and animal hosts. The first key step of its infection cycle is conidial germination, but there is limited information available on the molecular events supporting this process. We show here that germination is accompanied by a sharp decrease in expression of FoSir5, an ortholog of the human lysine deacetylase SIRT5. We observe that FoSir5 decrotonylates a subunit of the fungal pyruvate dehydrogenase complex (FoDLAT) at K148, resulting in inhibition of the activity of the complex in mitochondria. Moreover, FoSir5 decrotonylates histone H3K18, leading to a downregulation of transcripts encoding enzymes of aerobic respiration pathways. Thus, the activity of FoSir5 coordinates regulation in different organelles to steer metabolic flux through respiration. As ATP content is positively related to fungal germination, we propose that FoSir5 negatively modulates conidial germination in F. oxysporum through its metabolic impact. These findings provide insights into the multifaceted roles of decrotonylation, catalyzed by FoSir5, that support conidial germination in F. oxysporum.


Assuntos
Fusarium/crescimento & desenvolvimento , Fusarium/genética , Fusarium/metabolismo , Mitocôndrias/metabolismo , Esporos Fúngicos/crescimento & desenvolvimento , Esporos Fúngicos/genética , Esporos Fúngicos/metabolismo , Regulação Fúngica da Expressão Gênica , Mitocôndrias/genética , Doenças das Plantas/microbiologia
8.
mBio ; 12(6): e0232421, 2021 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-34933449

RESUMO

The Phox homology (PX) domain is a membrane recruitment module that binds to phosphoinositides (PI) mediating the selective sorting and transport of transmembrane proteins, lipids, and other critical cargo molecules via membrane trafficking processes. However, the mechanism of vesicular trafficking mediated by PX domain-containing proteins in phytopathogenic fungi and how this relates to the fungal development and pathogenicity remain unclear. Here, we systematically identified and characterized the functions of PX domain-containing proteins in the plant fungal pathogen Fusarium graminearum. Our data identified 14 PX domain-containing proteins in F. graminearum, all of which were required for plant infection and deoxynivalenol (DON) production, with the exception of FgMvp1 and FgYkr078. Furthermore, all the PX domain-containing proteins showed distinct localization patterns that were limited to the endosomes, vacuolar membrane, endoplasmic reticulum, cytoplasm, and hyphal septa/tips. Remarkably, among these proteins, FgBem1 targeted to surface crescent and septal pores and was retained at the septum pores even after actin constriction during septum development. Further analyses demonstrated that the surface crescent targeting of FgBem1 solely depended on its SH3 domains, while its septum and apex anchoring localization relied on its PX domain, which was also indispensable for reactive oxygen species (ROS) production, sexual development, and pathogenicity in F. graminearum. In summary, our study is the first detailed and comprehensive functional analysis of PX domain-containing proteins in filamentous fungi, and it provides new insight into the mechanism of FgBem1 involved in septum and apex anchorage mediated by its PX domain, which is necessary for sexual development and pathogenicity of F. graminearum. IMPORTANCE Fusarium head blight (FHB), caused predominantly by Fusarium graminearum, is an economically devastating disease of a wide range of cereal crops. Our previous study identified F. graminearum Vps17, Vps5, Snx41, and Snx4 as PX domain-containing proteins that were involved in membrane trafficking mediating the fungal development and pathogenicity, but the identity and biological roles of the remaining members of this protein family remain unknown in this model phytopathogen. In this study, we first unveiled all the PX domain-containing proteins in F. graminearum and then established their subcellular localizations and biological functions in relation to the fungal development and pathogenesis. We found 14 PX domain-containing proteins that localized to distinct subcellular organelles, including the endosomes, vacuolar membrane, endoplasmic reticulum, cytoplasm, and hyphal septa/tips. Of these proteins, FgBem1 was found to be essential for sexual development and virulence of F. graminearum. Further analyses showed that the PX domain of FgBem1 was indispensable for its functions in septum and apex anchorage, which, in turn, was necessary for ROS production and pathogenicity of F. graminearum. Our findings are important because it not only served as the first comprehensive characterization of the PX domain family proteins in a plant-pathogenic fungus but also uncovered the novel roles of the PX domain involved in septation and apex targeting, which could provide new fungicidal targets for controlling the devastating FHB disease.


Assuntos
Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Fusarium/genética , Genoma Fúngico , Membranas Intracelulares/microbiologia , Retículo Endoplasmático/microbiologia , Proteínas Fúngicas/genética , Fusarium/crescimento & desenvolvimento , Fusarium/metabolismo , Fusarium/patogenicidade , Regulação Fúngica da Expressão Gênica , Doenças das Plantas/microbiologia , Domínios Proteicos , Transporte Proteico , Tricotecenos/metabolismo , Vacúolos/microbiologia , Virulência
9.
Sci Rep ; 11(1): 22895, 2021 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-34819575

RESUMO

Biocontrol agents serve as a sustainable means of controlling wilt caused by the widespread plant pathogen, Fusarium oxysporum f. sp. lycopersici. The present study aimed to develop water dispersible granules (WDG) using response surface methodology (RSM) for Bacillus subtilis MTCC 2274 and Trichoderma harzianum MTCC 3928, and to compare their antifungal efficacy with other formulations. Further, characterization of the bioactive metabolites responsible for biocontrol was performed. A new microbial formulation, WDG, was developed in the present study with talcum powder (substrate), alginic acid (dispersing agent) and acacia gum (wetting agent) (suspensibility 82.23%; wetting time 2.5 min; dispersion time 10.08 min) that fulfilled the guidelines of Collaborative International Pesticides Analytical Council (CIPAC). In planta study demonstrated that WDG of B. subtilis showed maximum reduction in disease incidence (48%) followed by talc formulation of B. subtilis (44%) and WDG of T. harzianum (42%) with profound effect on plant growth promotion. B. subtilis and T. harzianum demonstrated protease (929 and 846 U ml-1 min-1), chitinase (33.69 and 154 U ml-1 min-1), and ß-1,3-glucanase (12.69 and 21.47 U ml-1 min-1) activities. Culture filtrates of B. subtilis and T. harzianum exhibited significant inhibition against mycelial growth of pathogen. The compounds present in the culture filtrates were identified with GC-MS as fatty acids, alkanes, phenols, benzene, pyran derivatives etc. The major non-volatile compounds in bioactive antifungal fraction were identified as derivatives of morpholine and piperdine for T. harzianum and B. subtilis, respectively. The findings propose a multivariate biocontrol mechanism against phytopathogen by production of hydrolytic enzymes, volatile and non-volatile compounds, together with development of an efficient next-generation formulation.


Assuntos
Bacillus subtilis/fisiologia , Agentes de Controle Biológico , Fusarium/patogenicidade , Hypocreales/fisiologia , Controle Biológico de Vetores , Doenças das Plantas/prevenção & controle , /microbiologia , Bacillus subtilis/metabolismo , Proteínas de Bactérias/metabolismo , Fusarium/crescimento & desenvolvimento , Fusarium/metabolismo , Hidrolases/metabolismo , Hidrólise , Hypocreales/metabolismo , Doenças das Plantas/microbiologia , Compostos Orgânicos Voláteis/metabolismo
10.
Toxins (Basel) ; 13(11)2021 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-34822575

RESUMO

Fusarium graminearum and Fusarium verticillioides are fungal pathogens that cause diseases in cereal crops, such as Fusarium head blight (FHB), seedling blight, and stalk rot. They also produce a variety of mycotoxins that reduce crop yields and threaten human and animal health. Several strategies for controlling these diseases have been developed. However, due to a lack of resistant cultivars and the hazards of chemical fungicides, efforts are now focused on the biocontrol of plant diseases, which is a more sustainable and environmentally friendly approach. In the present study, the lipopeptide mycosubtilin purified from Bacillus subtilis ATCC6633 significantly suppressed the growth of F. graminearum PH-1 and F. verticillioides 7600 in vitro. Mycosubtilin caused the destruction and deformation of plasma membranes and cell walls in F. graminearum hyphae. Additionally, mycosubtilin inhibited conidial spore formation and germination of both fungi in a dose-dependent manner. In planta experiments demonstrated the ability of mycosubtilin to control the adverse effects caused by F. graminearum and F. verticillioides on wheat heads and maize kernels, respectively. Mycosubtilin significantly decreased the production of deoxynivalenol (DON) and B-series fumonisins (FB1, FB2 and FB3) in infected grains, with inhibition rates of 48.92, 48.48, 52.42, and 59.44%, respectively. The qRT-PCR analysis showed that mycosubtilin significantly downregulated genes involved in mycotoxin biosynthesis. In conclusion, mycosubtilin produced by B. subtilis ATCC6633 was shown to have potential as a biological agent to control plant diseases and Fusarium toxin contamination caused by F. graminearum and F. verticillioides.


Assuntos
Bacillus subtilis/química , Fungicidas Industriais/farmacologia , Fusarium/efeitos dos fármacos , Micotoxinas/biossíntese , Fungicidas Industriais/química , Fusarium/crescimento & desenvolvimento , Fusarium/metabolismo , Lipoproteínas/química , Lipoproteínas/farmacologia
11.
Sci Rep ; 11(1): 22319, 2021 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-34785701

RESUMO

Vascular wilt caused by Fusarium udum Butler is the most important disease of pigeonpea throughout the world. F. udum isolate MTCC 2204 (M1) inoculated pigeonpea plants of susceptible (ICP 2376) and resistant (ICP 8863) cultivars were taken at invasion stage of pathogenesis process for transcriptomic profiling to understand defense signaling reactions that interplay at early stage of this plant-pathogen encounter. Differential transcriptomic profiles were generated through cDNA-AFLP from M1 inoculated resistant and susceptible pigeonpea root tissues. Twenty five percent of transcript derived fragments (TDFs) were found to be pathogen induced. Among them 73 TDFs were re-amplified and sequenced. Homology search of the TDFs in available databases and thorough study of scientific literature identified several pathways, which could play crucial role in defense responses of the F. udum inoculated resistant plants. Some of the defense responsive pathways identified to be active during this interaction are, jasmonic acid and salicylic acid mediated defense responses, cell wall remodeling, vascular development and pattering, abscisic acid mediated responses, effector triggered immunity, and reactive oxygen species mediated signaling. This study identified important wilt responsive regulatory pathways in pigeonpea which will be helpful for further exploration of these resistant components for pigeonpea improvement.


Assuntos
Cajanus , Resistência à Doença/genética , Fusarium/crescimento & desenvolvimento , Perfilação da Expressão Gênica , Doenças das Plantas , Cajanus/genética , Cajanus/microbiologia , Doenças das Plantas/genética , Doenças das Plantas/microbiologia
12.
Molecules ; 26(22)2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34834000

RESUMO

Enniatins are mycotoxins produced by Fusarium species contaminating cereals and various agricultural commodities. The co-occurrence of these mycotoxins in large quantities with other mycotoxins such as trichothecenes and the possible synergies in toxicity could lead to serious food safety problems. Using the agar dilution method, Ammoides pusilla was selected among eight Tunisian plants for the antifungal potential of its essential oil (EO) on Fusarium avenaceum mycelial growth and its production of enniatins. Two EO batches were produced and analyzed by GC/MS-MS. Their activities were measured using both contact assays and fumigant tests (estimated IC50 were 0.1 µL·mL-1 and 7.6 µL·L-1, respectively). The A. pusilla EOs and their volatiles inhibited the germination of spores and the mycelial growth, showing a fungistatic but not fungicidal activity. The accumulation of enniatins was also significantly reduced (estimated IC50 were 0.05 µL·mL-1 for the contact assays and 4.2 µL·L-1 for the fumigation assays). The most active batch of EO was richer in thymol, the main volatile compound found. Thymol used as fumigant showed a potent fungistatic activity but not a significant antimycotoxigenic activity. Overall, our data demonstrated the bioactivity of A. pusilla EO and its high potential to control F. avenaceum and its enniatins production in agricultural commodities.


Assuntos
Apiaceae/química , Depsipeptídeos/biossíntese , Fusarium/crescimento & desenvolvimento , Micélio/crescimento & desenvolvimento , Micotoxinas/biossíntese , Óleos Voláteis , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Timol/química , Timol/farmacologia
13.
Molecules ; 26(22)2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34834038

RESUMO

A series of novel menthol derivatives containing 1,2,4-triazole-thioether moiety were designed, synthesized, characterized structurally, and evaluated biologically to explore more potent natural product-based antifungal agents. The bioassay results revealed that at 50 µg/mL, some of the target compounds exhibited good inhibitory activity against the tested fungi, especially against Physalospora piricola. Compounds 5b (R = o-CH3 Ph), 5i (R = o-Cl Ph), 5v (R = m,p-OCH3 Ph) and 5x (R = α-furyl) had inhibition rates of 93.3%, 79.4%, and 79.4%, respectively, against P. piricola, much better than that of the positive control chlorothalonil. Compounds 5v (R = m,p-OCH3 Ph) and 5g (R = o-Cl Ph) held inhibition rates of 82.4% and 86.5% against Cercospora arachidicola and Gibberella zeae, respectively, much better than that of the commercial fungicide chlorothalonil. Compound 5b (R = o-CH3 Ph) displayed antifungal activity of 90.5% and 83.8%, respectively, against Colleterichum orbicalare and Fusarium oxysporum f. sp. cucumerinum. Compounds 5m (R = o-I Ph) had inhibition rates of 88.6%, 80.0%, and 88.0%, respectively, against F. oxysporum f. sp. cucumerinu, Bipolaris maydis and C. orbiculare. Furthermore, compound 5b (R = o-CH3 Ph) showed the best and broad-spectrum antifungal activity against all the tested fungi. To design more effective antifungal compounds against P. piricola, 3D-QSAR analysis was performed using the CoMFA method, and a reasonable 3D-QSAR model (r2 = 0.991, q2 = 0.514) was established. The simulative binding pattern of the target compounds with cytochrome P450 14α-sterol demethylase (CYP51) was investigated by molecular docking.


Assuntos
Fungicidas Industriais , Fusarium/crescimento & desenvolvimento , Simulação de Acoplamento Molecular , Fungicidas Industriais/síntese química , Fungicidas Industriais/química , Fungicidas Industriais/farmacologia , Mentol/química , Testes de Sensibilidade Microbiana , Relação Estrutura-Atividade , Sulfetos/síntese química , Sulfetos/química , Sulfetos/farmacologia , Triazóis/química
14.
Sci Rep ; 11(1): 21057, 2021 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-34702930

RESUMO

Nutrient disorder and presence of disease-causing agents in soilless media negatively influence the growth of muskmelon. To combat these issues, use of environmentally-friendly sanitation techniques is crucial for increased crop productivity. The study was conducted under greenhouse and field conditions to investigate the effect of two different sanitation techniques: steaming and formalin fumigation on various media's characteristics and their impact on muskmelon yield. Media: jantar, guar, wheat straw and rice hull and peat moss of 10% air-filled porosity and sanitized with formalin and steaming. Steaming of guar, jantar, and wheat straw increased the phosphorus (P) and potassium (K) concentrations by 13.80-14.86% and 6.22-8.45% over formalin fumigation. Likewise, P and K concentrations in muskmelon were higher under steaming. Steaming significantly inhibited the survival of Fusarium wilt sp. melonis, root knot nematode sp. meloidogyne and nitrifying bacteria in media than formalin fumigation. In conclusion, steaming decreased the prevalence of nitrifying bacteria and pathogens which thus improved the NO3--N:NH4+-N ratios, P and K nutritional balance both in the media and muskmelon transplants. Hence, steaming as an environment-friendly approach is recommended for soilless media. Further, optimization of steaming for various composts with different crops needs to be investigated with steaming teachnique.


Assuntos
Produção Agrícola , Cucumis melo , Formaldeído/farmacologia , Fumigação , Fusarium/crescimento & desenvolvimento , Doenças das Plantas/microbiologia , Cucumis melo/crescimento & desenvolvimento , Cucumis melo/microbiologia
15.
Molecules ; 26(20)2021 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-34684700

RESUMO

Background: The present study investigated the antifungal activity and mode of action of four Olea europaea leaf extracts, Thymus vulgaris essential oil (EO), and Boswellia carteri EO against Fusarium oxysporum. Methods:Fusarium oxysporum Lactucae was detected with the internal transcribed spacer (ITS) region. The chemical compositions of chloroform and dichloromethane extracts of O. europaea leaves and T. vulgaris EO were analyzed using GC-MS analysis. In addition, a molecular docking analysis was used to identify the expected ligands of these extracts against eleven F. oxysporum proteins. Results: The nucleotide sequence of the F. oxysporum Lactucae isolate was deposited in GenBank with Accession No. MT249304.1. The T. vulgaris EO, chloroform, dichloromethane and ethanol efficiently inhibited the growth at concentrations of 75.5 and 37.75 mg/mL, whereas ethyl acetate, and B. carteri EO did not exhibit antifungal activity. The GC-MS analysis revealed that the major and most vital compounds of the T. vulgaris EO, chloroform, and dichloromethane were thymol, carvacrol, tetratriacontane, and palmitic acid. Moreover, molecular modeling revealed the activity of these compounds against F. oxysporum. Conclusions: Chloroform, dichloromethane and ethanol, olive leaf extract, and T. vulgaris EO showed a strong effect against F. oxysporum. Consequently, this represents an appropriate natural source of biological compounds for use in healthcare. In addition, homology modeling and docking analysis are the best analyses for clarifying the mechanisms of antifungal activity.


Assuntos
Antifúngicos/farmacologia , Boswellia/química , Fusarium/efeitos dos fármacos , Óleos Voláteis/farmacologia , Olea/química , Extratos Vegetais/farmacologia , Thymus (Planta)/química , Fusarium/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana/métodos
16.
Toxins (Basel) ; 13(10)2021 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-34678972

RESUMO

Climate change will increase the co-occurrence of Fusarium verticillioides and Aspergillus flavus, along with their mycotoxins, in European maize. In this study, the expression profiles of two pathogenesis-related (PR) genes and four mycotoxin biosynthetic genes, FUM1 and FUM13, fumonisin pathway, and aflR and aflD, aflatoxin pathway, as well as mycotoxin production, were examined in kernels and in artificial medium after a single inoculation with F. verticillioides or A. flavus or with the two fungi in combination. Different temperature regimes (20, 25 and 30 °C) over a time-course of 21 days were also considered. In maize kernels, PR genes showed the strongest induction at 25 °C in the earlier days post inoculation (dpi)with both fungi inoculated singularly. A similar behaviour was maintained with fungi co-occurrence, but with enhanced defence response at 9 dpi under 20 °C. Regarding FUM genes, in the kernels inoculated with F. verticillioides the maximal transcript levels occurred at 6 dpi at 25 °C. At this temperature regime, expression values decreased with the co-occurrence of A. flavus, where the highest gene induction was detected at 20 °C. Similar results were observed in fungi grown in vitro, whilst A. flavus presence determined lower levels of expression along the entire time-course. As concerns afl genes, considering both A. flavus alone and in combination, the most elevated transcript accumulation occurred at 30 °C during all time-course both in infected kernels and in fungi grown in vitro. Regarding mycotoxin production, no significant differences were found among temperatures for kernel contamination, whereas in vitro the highest production was registered at 25 °C for aflatoxin B1 and at 20 °C for fumonisins in the case of single inoculation. In fungal co-occurrence, both mycotoxins resulted reduced at all the temperatures considered compared to the amount produced with single inoculation.


Assuntos
Aspergillus flavus/metabolismo , Fumonisinas/metabolismo , Fusarium/metabolismo , Zea mays/microbiologia , Aflatoxinas/genética , Aflatoxinas/metabolismo , Aspergillus flavus/genética , Aspergillus flavus/crescimento & desenvolvimento , Aspergillus flavus/patogenicidade , Fusarium/genética , Fusarium/crescimento & desenvolvimento , Fusarium/patogenicidade , Perfilação da Expressão Gênica , Micotoxinas/metabolismo , Temperatura
17.
Toxins (Basel) ; 13(10)2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-34679021

RESUMO

Fusarium head blight (FHB) is a devastating wheat disease, mainly caused by Fusarium graminearum (FG)-a deoxynivalenol (DON)-producing species. However, Fusarium avenaceum (FA), able to biosynthesize enniatins (ENNs), has recently increased its relevance worldwide, often in co-occurrence with FG. While DON is a well-known mycotoxin, ENN activity, also in association with DON, is poorly understood. This study aims to explore enniatin B (ENB) activity, alone or combined with DON, on bread wheat and on Fusarium development. Pure ENB, DON, and ENB+DON (10 mg kg-1) were used to assess the impacts on seed germination, seedling growth, cell death induction (trypan blue staining), chlorophyll content, and oxidative stress induction (malondialdehyde quantification). The effect on FG and FA growth was tested using ENB, DON, and ENB+DON (10, 50, and 100 mg kg-1). Synergistic activity in the reduction of seed germination, growth, and chlorophyll degradation was observed. Conversely, antagonistic interaction in cell death and oxidative stress induction was found, with DON counteracting cellular stress produced by ENB. Fusarium species responded to mycotoxins in opposite directions. ENB inhibited FG development, while DON promoted FA growth. These results highlight the potential role of ENB in cell death control, as well as in fungal competition.


Assuntos
Depsipeptídeos/toxicidade , Fusarium/efeitos dos fármacos , Doenças das Plantas/microbiologia , Tricotecenos/toxicidade , Triticum/efeitos dos fármacos , Clorofila/análise , Fusarium/crescimento & desenvolvimento , Germinação/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Sementes/efeitos dos fármacos , Sementes/crescimento & desenvolvimento
18.
Int J Mol Sci ; 22(20)2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34681652

RESUMO

Fusarium graminearum is a destructive fungal pathogen that threatens the production and quality of wheat, and controlling this pathogen is a significant challenge. As the cost-effective homolog of melatonin, 5-methoxyindole showed strong activity against F. graminearum. In the present study, our results showed the strong adverse activity of 5-methoxyindole against F. graminearum by inhibiting its growth, formation, and conidia germination. In addition, 5-methoxyindole could induce malformation, reactive oxygen species (ROS) accumulation, and cell death in F. graminearum hyphae and conidia. In response to 5-methoxyindole, F. graminearum genes involved in scavenging reactive oxygen species were significantly downregulated. Overall, these findings reveal the mechanism of antifungal action of melatonin-homolog 5-methoxyindole. To the best of our knowledge, this is the first report that a novel melatonin homolog confers strong antifungal activity against F. graminearum, and 5-methoxyindole is a potential compound for protecting wheat plants from F. graminearum infection.


Assuntos
Fusarium/efeitos dos fármacos , Indóis/farmacologia , Regulação para Baixo/efeitos dos fármacos , Proteínas Fúngicas/genética , Fusarium/crescimento & desenvolvimento , Fusarium/metabolismo , Melatonina/química , Melatonina/farmacologia , Testes de Sensibilidade Microbiana , Espécies Reativas de Oxigênio/metabolismo
19.
J Microbiol Biotechnol ; 31(9): 1241-1255, 2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34373438

RESUMO

This study was carried out to explore a non-chemical strategy for enhancing productivity by employing some antagonistic rhizobacteria. One hundred eighteen bacterial isolates were obtained from the rhizospheric zone of various crop fields of Gangwon-do, Korea, and screened for antifungal activity against Fusarium wilt (Fusarium oxysporum f. sp. lactucae) in lettuce crop under in vitro and in vivo conditions. In broth-based dual culture assay, fourteen bacterial isolates showed significant inhibition of mycelial growth of F. oxysporium f. sp. lactucae. All of the antagonistic isolates were further characterized for the antagonistic traits under in vitro conditions. The isolates were identified on the basis of biochemical characteristics and confirmed at their species level by 16S rRNA gene sequencing analysis. Arthrobacter sulfonivorans, Bacillus siamensis, Bacillus amyloliquefaciens, Pseudomonas proteolytica, four Paenibacillus peoriae strains, and Bacillus subtilis were identified from the biochemical characterization and 16S rRNA gene sequencing analysis. The isolates EN21 and EN23 showed significant decrease in disease severity on lettuce compared to infected control and other bacterial treatments under greenhouse conditions. Two bacterial isolates, EN4 and EN21, were evaluated to assess their disease reduction and growth promotion in lettuce in field conditions. The consortium of EN4 and EN21 showed significant enhancement of growth on lettuce by suppressing disease caused by F. oxysporum f. sp. lactucae respectively. This study clearly indicates that the promising isolates, EN4 (P. proteolytica) and EN21 (Bacillus siamensis), can be commercialized and used as biofertilizer and/or biopesticide for sustainable crop production.


Assuntos
Fenômenos Fisiológicos Bacterianos , Fusarium , Alface/crescimento & desenvolvimento , Doenças das Plantas/prevenção & controle , Inoculantes Agrícolas , Antibiose , Antifúngicos/metabolismo , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Bactérias/metabolismo , Agentes de Controle Biológico , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/microbiologia , Fusarium/crescimento & desenvolvimento , Fusarium/patogenicidade , Alface/microbiologia , Micélio/crescimento & desenvolvimento , Doenças das Plantas/microbiologia , Reguladores de Crescimento de Plantas/metabolismo , RNA Ribossômico 16S/genética , Rizosfera
20.
Molecules ; 26(16)2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34443447

RESUMO

Okara is a soybean transformation agri-food by-product, the massive production of which currently poses severe disposal issues. However, its composition is rich in seed storage proteins, which, once extracted, can represent an interesting source of bioactive peptides. Antimicrobial and antifungal proteins and peptides have been described in plant seeds; thus, okara is a valuable source of compounds, exploitable for integrated pest management. The aim of this work is to describe a rapid and economic procedure to isolate proteins from okara, and to produce an enzymatic proteolyzed product, active against fungal plant pathogens. The procedure allowed the isolation and recovery of about 30% of okara total proteins. Several proteolytic enzymes were screened to identify the proper procedure to produce antifungal compounds. Antifungal activity of the protein digested for 24 h with pancreatin against Fusarium and R. solani mycelial growth and Pseudomonas spp was assessed. A dose-response inhibitory activity was established against fungi belonging to the Fusarium genus. The exploitation of okara to produce antifungal bioactive peptides has the potential to turn this by-product into a paradigmatic example of circular economy, since a field-derived food waste is transformed into a source of valuable compounds to be used in field crops protection.


Assuntos
Antifúngicos/farmacologia , Enzimas/metabolismo , Proteínas de Plantas/metabolismo , Plantas/microbiologia , Polissacarídeos/metabolismo , Liofilização , Fusarium/efeitos dos fármacos , Fusarium/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Peso Molecular , Proteólise/efeitos dos fármacos , Alimentos de Soja , Espectrofotometria Ultravioleta , Tripsina/metabolismo , Inibidores da Tripsina/farmacologia
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