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1.
Int J Mol Sci ; 22(5)2021 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-33673430

RESUMO

To discover new compounds with broad spectrum and high activity, we designed a series of novel benzamides containing 1,2,4-oxadiazole moiety by bioisosterism, and 28 benzamides derivatives with antifungal activity were synthesized. These compounds were evaluated against four fungi: Botrytis cinereal, FusaHum graminearum, Marssonina mali, and Thanatephorus cucumeris. The results indicated that most of the compounds displayed good fungicidal activities, especially against Botrytis cinereal. For example, 10a (84.4%), 10d (83.6%), 10e (83.3%), 10f (83.1%), 10i (83.3%), and 10l (83.6%) were better than pyraclostrobin (81.4%) at 100 mg/L. In addition, the acute toxicity of 10f to zebrafish embryo was 20.58 mg/L, which was classified as a low-toxicity compound.


Assuntos
Antifúngicos/farmacologia , Benzamidas/farmacologia , Oxidiazóis/farmacologia , Peixe-Zebra/microbiologia , Animais , Ascomicetos/efeitos dos fármacos , Basidiomycota/efeitos dos fármacos , Benzamidas/síntese química , Benzamidas/química , Benzamidas/toxicidade , Botrytis/efeitos dos fármacos , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/microbiologia , Fusarium/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Oxidiazóis/síntese química , Oxidiazóis/química , Oxidiazóis/toxicidade , Peixe-Zebra/embriologia
2.
Eur J Med Chem ; 214: 113230, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33581553

RESUMO

To continue our ongoing studies on discovery of new potent antifungal leads, 43 novel pyrazole-aromatic containing carboxamides were rationally designed and synthesized. Bioassays indicated that most target compounds displayed good in vitro antifungal activities against Botrytis cinerea, Rhizoctonia cerealis and Sclerotinia sclerotiorum and in vivo antifungal activity against R. solani. Compound 11ea exhibited the most significant in vitro activity against R. cerealis (EC50 = 0.93 µg/mL) with about 2-fold more potent than a previously reported lead compound A1 (EC50 = 2.01 µg/mL), and about 11-fold more potent than the positive control/commercial succinate dehydrogenase inhibitor thifluzamide (EC50 = 23.09 µg/mL). Structure-activity relationship analysis and molecular docking simulations indicated that the presence of difluoromethyl pyrazole-(m-benzene) carboxamide scaffold obviously increased the antifungal activity. The further enzymatic bioassay showed that both thifluzamide and compound 11ea displayed excellent SDH inhibitory effects, and fluorescence quenching analysis suggested that they may share the same target SDH.


Assuntos
Antifúngicos/farmacologia , Basidiomycota/enzimologia , Derivados de Benzeno/farmacologia , Inibidores Enzimáticos/farmacologia , Pirazóis/farmacologia , Succinato Desidrogenase/antagonistas & inibidores , Antifúngicos/síntese química , Antifúngicos/química , Ascomicetos/efeitos dos fármacos , Basidiomycota/efeitos dos fármacos , Derivados de Benzeno/síntese química , Derivados de Benzeno/química , Botrytis/efeitos dos fármacos , Relação Dose-Resposta a Droga , Desenho de Fármacos , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Humanos , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Estrutura Molecular , Pirazóis/síntese química , Pirazóis/química , Relação Estrutura-Atividade , Succinato Desidrogenase/metabolismo
3.
Eur J Med Chem ; 214: 113246, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33582385

RESUMO

Thirty-three new 2, 3-dihydroquinolin-4(1H)-one analogues were designed, synthesized and characterized by IR, 1H NMR, 13C NMR and HRMS. The crystal structures of compounds 2g and 4l were characterized by single crystal X-ray diffraction. Their antifungal activities were determined against five plant pathogenic fungi namely Rhizoctonia solani, Fusarum graminearum, Helminthosporium maydis, Sclerotinia sclerotiorum and Botrytis cinerea. The results indicated that most of them revealed significant antifungal activity at 20 mg/L. Compound 4e showed the strongest antifungal activity against Botrytis cinerea and had better effects than the commercial fungicide fluopyram. Meanwhile, the active compounds were evaluated for their inhibitory activities against succinate dehydrogenase (SDH). The results displayed that they exhibited excellent activity. Compound 4e had better inhibitory activity than fluopyram. The molecular modeling results demonstrated that compound 4e could strongly bind to and interact with the binding sites of SDH. The inhibitory activity of 2, 3-dihydroquinolin-4(1H)-one derivatives against SDH has been reported for the first time.


Assuntos
Antifúngicos/farmacologia , Desenho de Fármacos , Quinolonas/farmacologia , Succinato Desidrogenase/antagonistas & inibidores , Antifúngicos/síntese química , Antifúngicos/química , Ascomicetos/efeitos dos fármacos , Botrytis/efeitos dos fármacos , Botrytis/enzimologia , Relação Dose-Resposta a Droga , Ligantes , Testes de Sensibilidade Microbiana , Modelos Moleculares , Estrutura Molecular , Quinolonas/síntese química , Quinolonas/química , Rhizoctonia/efeitos dos fármacos , Relação Estrutura-Atividade , Succinato Desidrogenase/metabolismo , Termodinâmica
4.
Int J Biol Macromol ; 168: 242-250, 2021 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-33309667

RESUMO

The main purpose of this study was to explore the ability of a novel silica/polysaccharide polymer-based formulation, namely, chitosan/silica nanocomposites (CSNs), to directly affect Botrytis cinerea in vitro and in inoculated berries, and indirectly to induce natural host resistance via enzymatic and nonenzymatic antioxidants against gray mold of table grapes. The results indicated a positive correlation in in vitro tests in terms of radial growth, spore germination and germ tube elongation, where those parameters were completely inhibited by CSN at 1%. SEM and TEM investigations showed that morphological and internal structural damage was observed in B. cinerea-hyphae/spores treated with CSN. Additionally, most of the treated spores were affected, and cellular vacuolization and cytoplasmic disorganization were observed. The results revealed that CSN reduced gray mold incidence and severity on inoculated berries directly and indirectly. In direct activity, CSN (1%) reduced mold incidence and severity by 100% compared to the control. In indirect activity, mold incidence and severity was reduced by 51% and 64%, respectively. CSN significantly increased superoxide dismutase, ascorbate peroxidase, peroxidase, total phenol and flavonoid at 48 h post-treatment by 1.2-, 1.6-, 1.3-, 1.3- and 1.6-fold, respectively, in grape-treated tissues. It could be concluded that CSN, as a promising alternative control method against gray mold of table grapes, can directly affect the pathogen and indirectly enhance the natural host resistance of the antioxidant system.


Assuntos
Botrytis/efeitos dos fármacos , Quitosana/química , Dióxido de Silício/química , Antifúngicos/farmacologia , Antioxidantes/farmacologia , Quitosana/farmacologia , Microbiologia de Alimentos , Fungos/efeitos dos fármacos , Hifas/efeitos dos fármacos , Nanocompostos/química , Doenças das Plantas/microbiologia , Espécies Reativas de Oxigênio/farmacologia , Dióxido de Silício/farmacologia , Vitis/efeitos dos fármacos , Vitis/microbiologia
5.
J Agric Food Chem ; 69(1): 491-500, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33382606

RESUMO

Fungal infections could cause tremendous decreases in crop yield and quality. Natural products, including flavonoids and (iso)quinolines, have always been an important source for lead discovery in medicinal and agricultural chemistry. To promote the discovery and development of new fungicides, a series of 3-(iso)quinolinyl-4-chromenone derivatives was designed and synthesized by the active substructure splicing principle and evaluated for their antifungal activities. The lead optimization was guided by bioactivity. The bioassay data revealed that the 3-quinolinyl-4-chromenone 13 showed significant in vitro activities against S. sclerotiorum, V. mali, and B. cinerea with EC50 values of 3.65, 2.61, and 2.32 mg/L, respectively. The 3-isoquinolinyl-4-chromenone 25 exhibited excellent in vitro activity against S. sclerotiorum with an EC50 value of 1.94 mg/L, close to that of commercial fungicide chlorothalonil (EC50 = 1.57 mg/L) but lower than that of boscalid (EC50 = 0.67 mg/L). For V. mali and B. cinerea, 3-isoquinolinyl-4-chromenone 25 (EC50 = 1.56, 1.54 mg/L) showed significantly higher activities than chlorothalonil (EC50 = 11.24, 2.92 mg/L). In addition, in vivo experiments proved that compounds 13 and 25 have excellent protective fungicidal activities with inhibitory rates of 88.24 and 94.12%, respectively, against B. cinerea at 50 mg/L, while the positive controls chlorothalonil and boscalid showed inhibitory rates of 76.47 and 97.06%, respectively. Physiological and biochemical studies showed that the primary action of mechanism of compounds 13 and 25 on S. sclerotiorum and B. cinerea may involve changing mycelial morphology and increasing cell membrane permeability. In addition, compound 13 may also affect the respiratory metabolism of B. cinerea. This study revealed that compounds 13 and 25 could be promising candidates for the development of novel fungicides in crop protection.


Assuntos
Benzopiranos/química , Benzopiranos/farmacologia , Fungicidas Industriais/química , Fungicidas Industriais/farmacologia , Botrytis/efeitos dos fármacos , Botrytis/crescimento & desenvolvimento , Relação Estrutura-Atividade
6.
Food Chem ; 337: 127772, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32777571

RESUMO

Chitosan can function a key role in plant resistant against Botrytis cinerea infection, while its mechanism is unclear in ripened fruits. In this study, we investigated the chitosan effect on two type of ripened fruits including strawberry and grapes (Kyoho and Shine-Muscat) when were infected with B. cinerea. Results showed that chitosan inhibited B. cinerea growth, increased phenolic compounds and cell wall composition, modulated oxidative stress and induced jasmonic acid (JA) production in ripened fruits. Data-independent acquisition (DIA) showed that 224 and 171 proteins were upregulated 1.5-fold by chitosan in Kyoho and Shine-Muscat grape, respectively. Topless-related protein 3 (TPR3) were identified and interacted with histone deacetylase 19 (HDAC19) and negatively regulated by JA and chitosan. Meanwhile, overexpression of VvTPR3 and VvHDAC19 reduced the stability of cell wall against B. cinerea in strawberry. Taken together, chitosan induces defense related genes and protect the fruit quality against Botrytis infection through JA signaling.


Assuntos
Botrytis/efeitos dos fármacos , Quitosana/farmacologia , Ciclopentanos/metabolismo , Fragaria/metabolismo , Oxilipinas/metabolismo , Vitis/metabolismo , Botrytis/fisiologia , Parede Celular/metabolismo , Fragaria/microbiologia , Frutas/metabolismo , Frutas/microbiologia , Histona Desacetilases/genética , Histona Desacetilases/metabolismo , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Proteínas de Plantas/antagonistas & inibidores , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Interferência de RNA , Esporos Fúngicos/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Vitis/microbiologia
7.
J Sci Food Agric ; 101(1): 229-239, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32627181

RESUMO

BACKGROUND: Synthetic fungicides are most commonly used for controlling postharvest disease of fruit, although they can cause the emergence of drug-resistant strains, environmental pollution and fruit safety issues. Bacillomycin D (BD), a novel antifungal lipopeptide, and chitosan (CTS) are applied for the preservation of cherry tomato. RESULTS: The combination of BD and CTS showed an additive inhibition on the growth of Rhizopus stolonifer and Botrytis cinerea compared to that of its individual compound. In addition, BD + CTS reduced the incidence of soft rot and gray mold in cherry tomato caused by R. stolonifer and B. cinerea, respectively. Tomato treated with BD + CTS exhibited a lower weight loss and higher firmness and higher contents of total soluble solids, titratable acidity and ascorbic acid compared to those treated with sterile water (control). The kinetics models demonstrated that the shelf life of cherry tomato treated with BD + CTS could be extended by approximately 15 days longer than the control. CONCLUSION: The utilization of BD + CTS provided a novel strategy for reducing postharvest fungal rot and maintaining the storage quality of cherry tomato. © 2020 Society of Chemical Industry.


Assuntos
Peptídeos Catiônicos Antimicrobianos/farmacologia , Botrytis/efeitos dos fármacos , Quitosana/farmacologia , Conservação de Alimentos/métodos , Fungicidas Industriais/farmacologia , Lycopersicon esculentum/microbiologia , Rhizopus/efeitos dos fármacos , Botrytis/crescimento & desenvolvimento , Sinergismo Farmacológico , Frutas/química , Frutas/microbiologia , Lycopersicon esculentum/química , Doenças das Plantas/microbiologia , Rhizopus/crescimento & desenvolvimento
8.
J Agric Food Chem ; 68(50): 14824-14831, 2020 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-33322905

RESUMO

Soil-borne pathogens and weeds could synergistically affect vegetable growth and result in serious losses. The investigation of antagonistic metabolites from a marine-derived entomopathogenic fungus, Beauveria felina, obtained polyhydroxy steroid (1), tricyclic diterpenoid (2), isaridin (3), and destruxin cyclodepsipeptides (4-6). The structures and absolute configurations of new 1-3 were elucidated by extensive spectroscopic and X-ray crystallographic analyses, as well as electronic circular dichroism (ECD) calculations. Compounds 1 and 2 showed antifungal activities against carbendazim-resistant strains of Botrytis cinerea, with the minimum inhibitory concentration (MIC) values ranging from 16 to 32 µg/mL, which were significantly better than those of carbendazim (MIC = 256 µg/mL). Compound 5 exhibited significant antagonistic activity against the radicle growth of Amaranthus retroflexus seedlings, which was almost identical to that of the positive control (2,4-dichlorophenoxyacetic acid). The structure-activity differences of 4-6 suggested that the Cl atom in HMPA1 and ß-Me in Pro2 should be the key factors to their herbicidal activities. Besides, compounds 3-6 showed moderate nematicidal activities against Meloidogyne incognita. These antagonistic effects of 1-6 were first reported and further revealed the synergistically antagonistic potential of B. felina to be developed into the biopesticide.


Assuntos
Antifúngicos/farmacologia , Antinematódeos/farmacologia , Beauveria/química , Beauveria/metabolismo , Animais , Antifúngicos/química , Antifúngicos/metabolismo , Antinematódeos/química , Antinematódeos/metabolismo , Beauveria/isolamento & purificação , Botrytis/efeitos dos fármacos , Botrytis/crescimento & desenvolvimento , Cristalografia por Raios X , Depsipeptídeos/química , Depsipeptídeos/metabolismo , Depsipeptídeos/farmacologia , Testes de Sensibilidade Microbiana , Estrutura Molecular , Água do Mar/microbiologia , Metabolismo Secundário , Tylenchoidea/efeitos dos fármacos , Tylenchoidea/crescimento & desenvolvimento
9.
J Agric Food Chem ; 68(52): 15440-15448, 2020 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-33332117

RESUMO

Eight new trichothecene derivatives, trichodermarins G-N (1-8), and two new cuparene derivatives, trichocuparins A (9) and B (10), as well as six known trichothecenes (11-16) were isolated from the fungal strain Trichoderma brevicompactum A-DL-9-2 obtained from the inner tissue of the marine red alga Chondria tenuissima. The structures and relative configurations of 1-10 were assigned by NMR and MS data, and the absolute configurations of 1, 2, and 9 were established by X-ray diffraction. Compound 8 features an aminosugar unit bond to the trichothecene framework for the first time, while 9 and 10 represent the first occurrence of cuparene sesquiterpenes in Trichoderma. All the isolates were assayed for growth inhibition of five phytopathogenic fungi (Botrytis cinerea, Cochliobolus miyabeanus, Fusarium oxysporum f. sp. cucumerium, Fusarium oxysporum f. sp. niveum, and Phomopsis asparagi) and four marine phytoplankton species (Amphidinium carterae, Heterocapsa circularisquama, Heterosigma akashiwo, and Prorocentrum donghaiense). Several of them exhibited significant inhibitory activities against the fungi and phytoplankton tested of which trichodermin (12) showed the highest antifungal and antimicroalgal activities with MIC and IC50 values being 4.0 and 0.82 µg/mL, respectively.


Assuntos
Fungicidas Industriais/farmacologia , Herbicidas/farmacologia , Hypocreales/química , Tricotecenos/farmacologia , /efeitos dos fármacos , Botrytis/efeitos dos fármacos , Botrytis/crescimento & desenvolvimento , Fungicidas Industriais/química , Fusarium/efeitos dos fármacos , Fusarium/crescimento & desenvolvimento , Herbicidas/química , Hypocreales/genética , Hypocreales/isolamento & purificação , Hypocreales/metabolismo , Microalgas/efeitos dos fármacos , Microalgas/crescimento & desenvolvimento , Estrutura Molecular , Fitoplâncton/efeitos dos fármacos , Fitoplâncton/crescimento & desenvolvimento , Água do Mar/microbiologia , Tricotecenos/química
10.
Int J Food Microbiol ; 334: 108807, 2020 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-32835997

RESUMO

The main goal of this study was to describe impact of preharvest application of methyl salicylate (MeSA), acetyl salicylic acid (ASA) and salicylic acid (SA) on the reduction of disease caused by Botrytis cinerea in two table grape cultivars ('Crimson' and 'Magenta'). Based on previous studies, MeSA and SA were applied at 0.1 and 0.01 mM for both cultivars, while ASA was applied at 1 mM in 'Crimson' and 0.1 mM in 'Magenta'. At time of harvest, berry maturity-quality attributes, bioactive compounds and antioxidant enzymes were determined. In addition, grapes were artificially inoculated with B. cinerea spores, and the berries were ranked for visual decay incidence after 5 days of inoculation. Salicylates preharvest treatments led to higher total acidity, content of bioactive compounds and activity of antioxidant enzymes in treated than in control berries. The application of salicylate derivatives induced resistance to B. cinerea spoilage, since higher percentage of berries with no symptoms was observed and on the contrary, the highest percentages of berries were obtained in control grapes. All preharvest treatments with SA, ASA and MeSA alleviated postharvest disease caused by B. cinerea probably due to increasing levels of phenolic compounds and activity of antioxidant enzymes, although the best results were obtained with MeSA at 0.1 mM. Also, for this treatment and dose, higher quality properties, such as higher concentrations of ascorbic, succinic and fumaric acids, were observed compared with no treated-grapes.


Assuntos
Antioxidantes/metabolismo , Botrytis/efeitos dos fármacos , Doenças das Plantas/prevenção & controle , Ácido Salicílico/farmacologia , Vitis/microbiologia , Aspirina/farmacologia , Resistência à Doença/efeitos dos fármacos , Conservação de Alimentos/métodos , Fenóis/metabolismo , Doenças das Plantas/microbiologia , Salicilatos/farmacologia , Vitis/efeitos dos fármacos , Vitis/metabolismo
11.
Sci Rep ; 10(1): 8196, 2020 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-32424195

RESUMO

An increasing interest in the development of products of natural origin for crop disease and pest control has emerged in the last decade. Here we introduce a new family of strawberry acyl glycosides (SAGs) formed by a trisaccharide (GalNAc-GalNAc-Glc) and a monounsaturated fatty acid of 6 to 12 carbon atoms linked to the glucose unit. Application of SAGs to Arabidopsis thaliana (hereafter Arabidopsis) plants triggered a transient oxidative burst, callose deposition and defense gene expression, accompanied by increased protection against two phytopathogens, Pseudomonas viridiflava and Botrytis cinerea. SAGs-induced disease protection was also demonstrated in soybean infected with the causal agent of target spot, Corynespora cassiicola. SAGs were shown to exhibit important antimicrobial activity against a wide-range of bacterial and fungal phytopathogens, most probably through membrane destabilization, and the potential use of SAGs as a biofungicide for postharvest disease protection was demonstrated on lemon fruits infected with Penicillium digitatum. Plant growth promotion by application of SAGs was shown by augmented primary root elongation, secondary roots development and increased siliques formation in Arabidopsis, whereas a significant increment in number of seed pods was demonstrated in soybean. Stimulation of radicle development and the induction of an auxin-responsive reporter system (DR5::GUS) in transgenic Arabidopsis plants, suggested that SAGs-stimulated growth at least partly acts through the auxin response pathway. These results indicate that strawberry fatty acid glycosides are promising candidates for the development of environmental-friendly products for disease management in soybean and lemon.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Fragaria/química , Glicosídeos/química , Glicosídeos/farmacologia , Doenças das Plantas/prevenção & controle , Arabidopsis/efeitos dos fármacos , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/microbiologia , Bioensaio , Botrytis/efeitos dos fármacos , Botrytis/fisiologia , Doenças das Plantas/microbiologia , Pseudomonas/efeitos dos fármacos , Pseudomonas/fisiologia
12.
Food Chem ; 324: 126891, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32339790

RESUMO

We determined whether heat and chemical treatments could reduce the decay of kiwifruit caused by Botrytis cinerea during postharvest storage. Kiwifruits were treated with 5 g/L (w/v) potassium sorbate (PS), with a 48 °C hot water treatment (HT), and with a combined treatment (HT + PS). Mycelial growth of B. cinerea and the postharvest quality of 'XuXiang' kiwifruits were evaluated. HT + PS significantly inhibited mycelial growth, germ tube growth, and spore germination of B. cinerea. This treatment also reduced the incidence of gray mold in kiwifruit postharvest, and enhanced activities of defense-related enzymes in kiwifruit tissues. Compared with the control, all treatments resulted in lower malondialdehyde (MDA) contents and higher total phenolic contents in kiwifruits. HT + PS also increased the activities of chitinase and ß-1,3-glucanase and the transcript levels of their encoding genes. HT + PS can improve kiwifruit quality and reduce decay during postharvest storage.


Assuntos
Actinidia/microbiologia , Botrytis/efeitos dos fármacos , Ácido Sórbico/farmacologia , Actinidia/química , Actinidia/enzimologia , Botrytis/genética , Quitinases/genética , Quitinases/metabolismo , DNA Fúngico/metabolismo , Qualidade dos Alimentos , Frutas/química , Frutas/enzimologia , Frutas/microbiologia , Glucana 1,3-beta-Glucosidase/genética , Glucana 1,3-beta-Glucosidase/metabolismo , Temperatura Alta , Malondialdeído/metabolismo , Fenóis/metabolismo
13.
PLoS One ; 15(4): e0224643, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32348310

RESUMO

Grey mould is caused by the ascomycetes Botrytis cinerea in a range of crop hosts. As a biological control agent, the nucleoside antibiotic wuyiencin has been industrially produced and widely used as an effective fungicide. To elucidate the effects of wuyiencin on the transcriptional regulation in B. cinerea, we, for the first time, report a genome-wide transcriptomic analysis of B. cinerea treated with wuyiencin. 2067 genes were differentially expressed, of them, 886 and 1181 genes were significantly upregulated and downregulated, respectively. Functional categorization indicated that transcript levels of genes involved in amino acid metabolism and those encoding putative secreted proteins were altered in response to wuyiencin treatment. Moreover, the expression of genes involved in protein synthesis and energy metabolism (oxidative phosphorylation) and of those encoding ATP-binding cassette transporters was markedly upregulated, whereas that of genes participating in DNA replication, cell cycle, and stress response was downregulated. Furthermore, wuyiencin resulted in mycelial malformation and negatively influenced cell growth rate and conidial yield in B. cinerea. Our results suggest that this nucleoside antibiotic regulates all aspects of cell growth and differentiation in B. cinerea. To summarize, some new candidate pathways and target genes that may related to the protective and antagonistic mechanisms in B. cinerea were identified underlying the action of biological control agents.


Assuntos
Antifúngicos/farmacologia , Botrytis/genética , Farmacorresistência Fúngica , Transcriptoma , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Botrytis/efeitos dos fármacos , Botrytis/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica , Regulação para Cima
14.
Food Chem ; 321: 126701, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32283502

RESUMO

The antifungal activity of a library of twenty-four aromatic methoximes was examined against five representative postharvest phytopathogenic fungi. The panel included Penicillium digitatum, Penicillium italicum, Rhizopus stolonifer, Botrytis cinerea and Monilinia fructicola, all of which cause relevant economic losses worldwide as a result of affecting harvested fruits. The minimum inhibitory concentrations and minimum fungicidal concentrations of each compound were defined and the main structure-activity relationships were determined. Although other congeners were more potent, drug likeliness considerations pointed to the methoxime derived from 2,4-dihydroxypropiophenone as the compound with the most suitable profile. The morphology of the colonies of the fungal strains treated with the methoxime was examined microscopically and the compound was also tested in freshly harvested peaches and oranges, exhibiting promising control profiles in both fruits, similar to those of the commercial agents Imazalil and Carbendazim.


Assuntos
Antifúngicos/química , Antifúngicos/farmacologia , Frutas/microbiologia , Oximas/química , Ascomicetos/efeitos dos fármacos , Botrytis/efeitos dos fármacos , Citrus sinensis/efeitos dos fármacos , Citrus sinensis/microbiologia , Frutas/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Oximas/farmacologia , Penicillium/efeitos dos fármacos , Prunus persica/efeitos dos fármacos , Prunus persica/microbiologia , Rhizopus/efeitos dos fármacos , Relação Estrutura-Atividade
15.
Sci Rep ; 10(1): 4498, 2020 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-32161291

RESUMO

Volatile organic compounds (VOCs) produced by Aureobasidium pullulans were investigated for antagonistic actions against Alternaria alternata and Botrytis cinerea. Conidia germination and colony growth of these two phytopathogens were suppressed by A. pullulans VOCs. A novel experimental setup was devised to directly extract VOCs using solid-phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS) from antagonist-pathogen culture headspace. The proposed system is a robust method to quantify microbial VOCs using an internal standard. Multivariate curve resolution-alternating least squares deconvolution of SPME-GC-MS spectra identified fourteen A. pullulans VOCs. 3-Methyl-1-hexanol, acetone, 2-heptanone, ethyl butyrate, 3-methylbutyl acetate and 2-methylpropyl acetate were newly identified in A. pullulans headspace. Partial least squares discriminant analysis models with variable importance in projection and selectivity ratio identified four VOCs (ethanol, 2-methyl-1-propanol, 3-methyl-1-butanol and 2-phenylethanol), with high explanatory power for discrimination between A. pullulans and pathogen. The antifungal activity and synergistic interactions of the four VOCs were evaluated using a Box-Behnken design with response surface modelling. Ethanol and 2-phenylethanol are the key inhibitory A. pullulans VOCs against both B. cinerea and A. alternata. Our findings introduce a novel, robust, quantitative approach for microbial VOCs analyses and give insights into the potential use of A. pullulans VOCs to control B. cinerea and A. alternata.


Assuntos
Alternaria/efeitos dos fármacos , Ascomicetos/química , Botrytis/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Microextração em Fase Sólida , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/farmacologia , Antifúngicos/química , Antifúngicos/farmacologia , Metabolômica/métodos , Testes de Sensibilidade Microbiana
16.
Plant Physiol Biochem ; 150: 39-48, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32112998

RESUMO

Triunsaturated fatty acids are substrates for the synthesis of the defense hormone jasmonate which plays roles in resistance to numerous fungal pathogens. However, relatively little is known about other potential roles of di-unsaturated and triunsaturated fatty acids in resistance to fungal pathogens - in particular those that can attack plants at the seedling stage. We examined the roles of polyunsaturated fatty acids (PUFAs) in Arabidopsis thaliana during attack by the necrotrophic pathogen, Botrytis cinerea. We found that PUFA-deficient Arabidopsis mutants (fad2-1, fad2-3 and fad3-2 fad7-2 fad8 [fad trip]) displayed an unexpectedly strong resistance to B. cinerea at the cotyledon stage. Preliminary analyses revealed no changes in the expression of defense genes, however cuticle permeability defects were detected in both fad2-1 and fad trip mutants. Analysis of B. cinerea development on the surface of cotyledons revealed arrested hyphal growth on fad2-3 and fad trip mutants and 28% reduction in fungal adhesion on fad2-3 cotyledons. Surface metabolite analysis from the cotyledons of PUFA mutants led to the identification of 7-methylsulfonylheptyl glucosinolate (7MSOHG), which over-accumulated on the plant surface. We linked the appearance of 7MSOHG to defects in cuticle composition and permeability of mutants and show that its appearance correlates with resistance to B. cinerea.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Botrytis , Glucosinolatos , Antifúngicos/farmacologia , Arabidopsis/química , Arabidopsis/genética , Arabidopsis/microbiologia , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Botrytis/efeitos dos fármacos , Resistência à Doença/genética , Ácidos Graxos Dessaturases/genética , Ácidos Graxos Dessaturases/metabolismo , Regulação da Expressão Gênica de Plantas , Glucosinolatos/genética , Glucosinolatos/farmacologia
17.
Eur J Med Chem ; 194: 112253, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32222678

RESUMO

The prevention and control of plant diseases and insect pests is the most crucial issue facing crop protection. To discover novel pesticide candidates with diverse chemical structures from natural products, a series of luotonin A analogues were designed, synthesized and evaluated for their antifungal and insecticidal activities. Most of these compounds exhibited potent activity against Botrytis cinerea, Magnaporthe oryzae and Aphis craccivora. Among them, the antifungal activity of compound 10s against B. cinerea was comparable to azoxystrobin (EC50 = 0.09 mM) and against M. oryzae (EC50 = 0.19 mM) was slightly weaker than that of azoxystrobin (EC50 = 0.17 mM). Compounds 10k and 10o are the most active compounds against A. craccivora having identical mortality value of 42.05% at 50 µg/mL, respectively, which were slightly lower than pymetrozine (51.14%) at the same concentration. Revealed morphological changes of the fungal cell surface by scanning electron microscopy indicated that luotonin A analogues might exert their antifungal activity by destroying fungal cell membrane and cell wall. Furthermore, the results of the in vivo protective and curative activities of the compound 10s against S. sclerotiorum and B. cinerea showed that the curative effect was stronger than its protective effect and the curative effects reached 67.17% and 73.82% at 80 µg/mL respectively. The above results further demonstrated the potential of luotonin A analogues as novel fungicides and insecticides.


Assuntos
Alcaloides/farmacologia , Produtos Biológicos/farmacologia , Descoberta de Drogas , Fungicidas Industriais/farmacologia , Inseticidas/farmacologia , Pirróis/farmacologia , Quinonas/farmacologia , Alcaloides/síntese química , Alcaloides/química , Animais , Afídeos/efeitos dos fármacos , Produtos Biológicos/síntese química , Produtos Biológicos/química , Botrytis/efeitos dos fármacos , Relação Dose-Resposta a Droga , Fungicidas Industriais/síntese química , Fungicidas Industriais/química , Inseticidas/síntese química , Inseticidas/química , Magnaporthe/efeitos dos fármacos , Estrutura Molecular , Pirróis/síntese química , Pirróis/química , Quinonas/síntese química , Quinonas/química , Relação Estrutura-Atividade
18.
Appl Environ Microbiol ; 86(9)2020 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-32086310

RESUMO

Many fungal pathogens have short generation times, large population sizes, and mixed reproductive systems, providing high potential to adapt to heterogeneous environments of agroecosystems. Such adaptation complicates disease management and threatens food production. A better understanding of pathogen population biology in such environments is important to reveal key aspects of adaptive divergence processes to allow improved disease management. Here, we studied how evolutionary forces shape population structure of Botrytis cinerea, the causal agent of gray mold, in the Pacific Northwest agroecosystems. Populations of B. cinerea from adjacent fields of small fruit hosts were characterized by combining neutral markers (microsatellites) with markers that directly respond to human-induced selection pressures (fungicide resistance). Populations were diverse, without evidence for recombination and association of pathogen genotype with host. Populations were highly localized with limited migration even among adjacent fields within a farm. A fungicide resistance marker revealed strong selection on population structure due to fungicide use. We found no association of resistance allele with genetic background, suggesting de novo development of fungicide resistance and frequent extinction/recolonization events by different genotypes rather than the spread of resistance alleles among fields via migration of a dominant genotype. Overall our results showed that in agroecosystems, B. cinerea populations respond strongly to selection by fungicide use with greater effect on population structure compared to adaptation to host plant species. This knowledge will be used to improve disease management by developing strategies that limit pathogen local adaptation to fungicides and other human-induced selection pressures present in Pacific Northwest agroecosystems and elsewhere.IMPORTANCE Agroecosystems represent an efficient model for studying fungal adaptation and evolution in anthropogenic environments. In this work, we studied what evolutionary forces shape populations of one of the most important fungal plant pathogens, B. cinerea, in small fruit agroecosystems of the Pacific Northwest. We hypothesized that host, geographic, and anthropogenic factors of agroecosystems structure B. cinerea populations. By combining neutral markers with markers that directly respond to human-induced selection pressures, we show that pathogen populations are highly localized and that selection pressure caused by fungicide use can have a greater effect on population structure than adaptation to host. Our results give a better understanding of population biology and evolution of this important plant pathogen in heterogeneous environments but also provide a practical framework for the development of efficient management strategies by limiting pathogen adaptation to fungicides and other human-induced selection pressures present in agroecosystems of the Pacific Northwest and elsewhere.


Assuntos
Evolução Biológica , Botrytis/genética , Frutas/microbiologia , Interações Hospedeiro-Patógeno , Seleção Genética , Botrytis/efeitos dos fármacos , Botrytis/efeitos da radiação , Produção Agrícola , Oregon , Washington
19.
Molecules ; 25(4)2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-32069902

RESUMO

Antimicrobial resistance to conventional antibiotics and the limited alternatives to combat plant-threatening pathogens are worldwide problems. Antibiotic lipopeptides exert remarkable membrane activity, which usually is not prone to fast resistance formation, and often show organism-type selectivity. Additional modes of action commonly complement the bioactivity profiles of such compounds. The present work describes a multicomponent-based methodology for the synthesis of cyclic polycationic lipopeptides with stabilized helical structures. The protocol comprises an on solid support Ugi-4-component macrocyclization in the presence of a lipidic isocyanide. Circular dichroism was employed to study the influence of both macrocyclization and lipidation on the amphiphilic helical structure in water and micellar media. First bioactivity studies against model phytopathogens demonstrated a positive effect of the lipidation on the antimicrobial activity.


Assuntos
Antifúngicos/química , Lactamas/química , Lipopeptídeos/química , Peptídeos Cíclicos/química , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Antifúngicos/síntese química , Antifúngicos/farmacologia , Botrytis/efeitos dos fármacos , Lipopeptídeos/síntese química , Lipopeptídeos/farmacologia , Peptídeos Cíclicos/síntese química , Peptídeos Cíclicos/farmacologia , Phytophthora infestans/efeitos dos fármacos
20.
Carbohydr Polym ; 234: 115903, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32070523

RESUMO

In this study, 2-urea-chitosan oligosaccharide derivatives (2-urea-COS derivatives) and 2,6-diurea-chitosan oligosaccharide derivatives (2,6-diurea-COS derivatives) were successfully designed and synthesized via intermediate 2-methoxyformylated chitosan oligosaccharide. All samples were characterized and compared based on FT-IR, 1H NMR spectroscopy, and elemental analysis. The antifungal effects of COS derivatives were tested against Fusarium oxysporum f. sp. niveum, Phomopsis asparagus, and Botrytis cinereal. Their antioxidant properties, including superoxide radicals' scavenging activity, hydroxyl radicals' scavenging activity, and DPPH radicals' scavenging activity were also explored within different concentrations. COS derivatives bearing urea groups showed improved bioactivity compared with pristine COS and 2,6-diurea-COS derivatives had a higher biological activity than 2-urea-COS derivatives in tested concentrations. Additionally, L929 cells were used to carry out cytotoxicity test of COS and COS derivatives by CCK-8 assay. The results indicated that some of samples showed low cytotoxicity. These findings offered a suggestion that COS derivatives bearing urea groups are promising biological materials.


Assuntos
Antifúngicos/farmacologia , Antioxidantes/farmacologia , Quitosana/farmacologia , Oligossacarídeos/farmacologia , Antifúngicos/síntese química , Antifúngicos/química , Antioxidantes/síntese química , Antioxidantes/química , Ascomicetos/efeitos dos fármacos , Compostos de Bifenilo/antagonistas & inibidores , Botrytis/efeitos dos fármacos , Quitosana/química , Fusarium/efeitos dos fármacos , Radical Hidroxila/antagonistas & inibidores , Testes de Sensibilidade Microbiana , Estrutura Molecular , Oligossacarídeos/síntese química , Oligossacarídeos/química , Picratos/antagonistas & inibidores , Superóxidos/antagonistas & inibidores
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