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1.
Bioresour Technol ; 399: 130588, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38490460

RESUMO

In this work, a novel biofilm-based fermentation of Beauveria bassiana was employed to convert R-2- phenoxypropionic acid (R-PPA) to R-2-(4-hydroxyphenoxy) propionic acid (R-HPPA). The biofilm culture model of Beauveria bassiana produced a significantly higher R-HPPA titer than the traditional submerged fermentation method. Mannitol dosage, tryptone dosage, and initial pH were the factors that played a significant role in biofilm formation and R-HPPA synthesis. Under the optimal conditions, the maximum R-HPPA titer and productivity approached 22.2 g/L and 3.2 g/(L·d), respectively. A two-stage bioreactor combining agitation and static incubation was developed to further increase R-HPPA production. The process was optimized to achieve 100 % conversion of R-PPA, with a maximum R-HPPA titer of 50 g/L and productivity of 3.8 g/(L·d). This newly developed biofilm-based two-stage fermentation process provides a promising strategy for the industrial production of R-HPPA and related hydroxylated aromatic compounds.


Assuntos
Beauveria , Fermentação , Beauveria/química , Reatores Biológicos , Propionatos
2.
J Agric Food Chem ; 71(25): 9782-9795, 2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37310400

RESUMO

Sour rot, caused by Geotrichum citri-aurantii, is a major postharvest disease in citrus and results in significant economic losses. The genus Beauveria is recognized as a promising source of biocontrol agents for agricultural applications. Herein, we established a targeted strategy by integrating genomics and metabolomics to accelerate the discovery of new cyclopeptides from antagonistic metabolites produced by the marine-derived fungus Beauveria felina SYSU-MS7908. As a result, we isolated and characterized seven cyclopeptides, including six new molecules, isaridins I-N (1-6). Their chemical structures and conformational analysis were extensively elucidated using spectroscopic techniques (NMR, HRMS, and MS'MS data), modified Mosher's and Marfey's methods, and single-crystal X-ray diffraction. Notably, isaridin K (3) contains a peptide backbone with an N-methyl-2-aminobutyric acid residue rarely found in natural cyclopeptides. Bioassays showed that compound 2 could significantly inhibit the mycelial growth of G. citri-aurantii by destroying the cell membrane. These findings provide an effective strategy for searching for new fungal peptides for potential agrochemical fungicides and also pave the way for further exploration of applications in agriculture, food, and medicine.


Assuntos
Beauveria , Citrus , Antifúngicos/farmacologia , Beauveria/química , Peptídeos Cíclicos/farmacologia , Metabolômica , Citrus/microbiologia
3.
Mar Drugs ; 20(9)2022 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-36135773

RESUMO

Chemical investigation of a coculture of the marine-derived fungi Beauveria felina KMM 4639 and Aspergillus carneus KMM 4638 led to the identification of three new drimane-type sesquiterpenes, asperflavinoids B, D and E (2, 4, 5), and nine previously reported related compounds. The structures of these compounds were established using spectroscopic methods and by comparison with known analogues. We also investigated the cytotoxic activity of the isolated compounds against several cancer and normal cell lines. Asperflavinoid C (3) and ustusolate E (9) exerted a significant effect on human breast cancer MCF-7 cell viability, with IC50 values of 10 µM, and induced in caspase-dependent apoptosis and arrest of the MCF-7 cell cycle in the G2/M phase in these cells.


Assuntos
Antineoplásicos , Beauveria , Sesquiterpenos , Antineoplásicos/química , Aspergillus , Beauveria/química , Linhagem Celular Tumoral , Técnicas de Cocultura , Humanos , Estrutura Molecular , Sesquiterpenos Policíclicos , Sesquiterpenos/química
4.
J Appl Microbiol ; 133(2): 1063-1077, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35598181

RESUMO

AIMS: The leaf-feeding pest Cerotoma arcuata tingomariana (Bechyné) (Coleoptera: Chrysomelidae) produces huge economic losses in different crops. This study aimed to produce conidia by semisolid-state fermentation and to establish the insecticidal activity of two formulation prototypes based on a native Beauveria bassiana isolate for controlling this pest. METHODS AND RESULTS: A novel fabric-based semisolid-state fermentation strategy for quick and large-scale conidia production was performed and characterized. Conidia were formulated as an emulsifiable concentrate (EC) and a water-dispersible granulate (WG). Afterwards, the mortality of C. a. tingomariana adults was assessed. A conidia concentration of 2.9 × 109 conidia cm-2 was obtained after 9 days-course fermentation and a yield of 33.4 g kg-1 dry-substrate. CONCLUSIONS: The polyester fabric-based fermentation is an efficient technique for producing and collecting B. bassiana spores. Regarding LC90 , the potency analysis showed that the EC was 21-fold more potent than the non-formulated conidia, and ~ 2.6-fold more potent than the WG. SIGNIFICANCE AND IMPACT OF STUDY: A high throughput fermentation based on polyester fabric as support for B. bassiana conidia production and subsequent formulation as an EC comprises a promising strategy for obtaining a bioproduct to control adults of C. a. tingomariana and other Chrysomelidae pests.


Assuntos
Beauveria , Besouros , Animais , Beauveria/química , Controle Biológico de Vetores/métodos , Poliésteres , Esporos Fúngicos/química
5.
Sci Rep ; 11(1): 12020, 2021 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-34103637

RESUMO

Bemisia tabaci is one of the most notorious agricultural pests in the world. A vicious circle among insect resistance, dose increased, environment and human body impaired as the overuse of synthetic pesticides are becoming increasingly evident. Entomopathogenic Beauveria sp. is known as an effective natural enemy to control B. tabaci. Therefore, this study aimed to purify and identify the biological compounds from Beauveria sp. LY2 via extensive chromatographic techniques, NMR and MS and evaluated for their insecticidal activities against B. tabaci via contact and feeding assay. The outcome identified that one new cerebroside, cerebroside F (1), nine known compounds, cerebroside B (2), bassiatin (3), methyl 1,4-dihydro-4-oxo-2-quinolinecarboxylate (4), cerevisterol (5), 9-hydroxycerevisterol (6), 6-dehydrocerevisterol (7), (22E,24R)-ergosta-8(14),22-diene-3ß,5α,6ß,7α-tetrol (8), melithasterol B (9) and ergosterol peroxide (10) were isolated. Among the known compounds, methyl 1,4-dihydro-4-oxo- 2-quinolinecarboxylate (4) was isolated from natural origin for the first time. It is demonstrable from the results that compounds 3, 4 and 7 strongly featured insecticidal activities against B. tabaci, being the LC50 value as 10.59, 19.05, 26.59 µg/mL respectively in contact as well as 11.42, 5.66, 5.65 µg/mL respectively in feeding experiment. Moreover, no adverse effect on plant growth/height or phytotoxicity was observed on pepper, cucumber, tomato and cotton. The data from the current study has provided the foundation for the use of newly purified compounds against Bemisia tabaci as an alternative to synthetic chemical compounds.


Assuntos
Beauveria/química , Hemípteros/crescimento & desenvolvimento , Inseticidas , Compostos Fitoquímicos , Animais , Avaliação de Medicamentos , Inseticidas/química , Inseticidas/isolamento & purificação , Inseticidas/farmacologia , Compostos Fitoquímicos/química , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia
6.
J Nat Prod ; 84(4): 1244-1253, 2021 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-33754723

RESUMO

An investigation of an endolichenic Beauveria sp. led to the discovery of seven new cyclotetradepsipeptides, beauveamides A-G (2-8), along with the known beauverolide Ka (1). All incorporate a 3-hydroxy-4-methyldecanoic acid (HMDA) moiety in their structures. Their configuration was determined through Marfey's, J-based configuration analysis, and NMR computational methods, representing the first time that the stereostructures of HMDA-moiety-containing cyclotetradepsipeptides have been established. Compounds 1 and 2 exhibited protecting effects on HEI-OC1 cells at 10 µM, while 1, 4, and 5 could stimulate glucose uptake in cultured rat L6 myoblasts at 50 µM. Compound 1 showed dose-dependent activity in both L6 myoblasts and myotubes.


Assuntos
Beauveria/química , Ácidos Decanoicos , Depsipeptídeos/farmacologia , Mioblastos/efeitos dos fármacos , Animais , Ascomicetos , Linhagem Celular , China , Humanos , Líquens/microbiologia , Estrutura Molecular , Mioblastos/metabolismo , Ratos
7.
Fitoterapia ; 148: 104781, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33259889

RESUMO

Five new tremulane sesquiterpenoids were isolated from co-culture of endophyte Irpex lacteus, phytopathogen Nigrospora oryzae, and entomopathogen Beauveria bassiana. All compounds showed obvious antifeedant activities against silkworm with inhibition percentages of 73-99%, at concentrations of 50 µg/cm2. Compound 11 indicated notable antifeedant activity with inhibition percentage of 93% at concentration of 6.25 µg/cm2 among them. Compounds 2, 3, 4, 8, 9, 15 and 16 indicated anti-fungal activities against I. lacteus with MIC values ≤8 µg/mL, compounds 11, 12, 16-18 showed significant anti-fungal activity against N. oryzae with MICs ≤ 4 µg/mL, and compounds 2, 5, 12 and 18 indicated significant anti-fungal activity against B. bassiana with MICs ≤ 8 µg/mL. In addition, the I. lacteus should unite B. bassiana to inhibit the production of phytotoxins from N. oryzae in the ternary culture.


Assuntos
Ascomicetos/química , Beauveria/química , Bombyx/efeitos dos fármacos , Fungicidas Industriais/farmacologia , Polyporales/química , Sesquiterpenos/farmacologia , Animais , Ascomicetos/efeitos dos fármacos , China , Técnicas de Cocultura , Dendrobium/microbiologia , Endófitos/química , Fermentação , Fungicidas Industriais/isolamento & purificação , Testes de Sensibilidade Microbiana , Estrutura Molecular , Polyporales/efeitos dos fármacos , Sementes/microbiologia , Sesquiterpenos/isolamento & purificação
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 Chromatogr A ; 1634: 461626, 2020 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-33166889

RESUMO

An untargeted LC-MS/MS-based molecular networking method was established for the automatic determination of variants of enniatin and beauvericin from both fungal cultures and naturally contaminated samples. Using this method, a large number of samples can be efficiently analyzed for the presence of enniatin- and beauvericin-related compounds. As proof of concept, 26 cultures, derived from 13 fungal strains in the genera of Fusarium, Beauveria, and Diaporthe, as well as 46 food samples were analyzed. Four enniatin- and three beauvericin-producing fungi were newly discovered. Among them, the production of beauvericin by Fusarium sp. 190-20-2 was further confirmed by the presence of a beauvericin biosynthesis gene cluster in its genomic sequence. Additionally, 17 enniatin congeners, including one new isomer of enniatin A, and three previously unreported bassianolide analogues were detected from an enniatin-producing fungus, Fusarium sp. 17-048, and a beauvericin-producing fungus, Beauveria sp. 186-069, respectively. The structures of the detected compounds were tentatively determined by a series of product ions of their sodium adducts. The new isomer of enniatin A was further confirmed by NMR spectra. A preliminary survey of food samples showed that enniatins were prevalent in the tested wheat flour and noodle samples, whereas beauvericin was only discovered in cornflour powder samples.


Assuntos
Beauveria/química , Cromatografia Líquida , Depsipeptídeos/análise , Microbiologia de Alimentos/métodos , Fusarium/química , Espectrometria de Massas em Tandem , Depsipeptídeos/isolamento & purificação , Farinha/microbiologia , Peptídeos Cíclicos/química , Triticum/microbiologia
10.
J Invertebr Pathol ; 177: 107480, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33022282

RESUMO

Hypocrealean entomopathogenic fungi (EPF) (Sordariomycetes, Ascomycota) are natural regulators of insect populations in terrestrial environments. Their obligately-killing life-cycle means that there is likely to be strong selection pressure for traits that allow them to evade the effects of the host immune system. In this study, we quantified the effects of cordycepin (3'-deoxyadenosine), a secondary metabolite produced by Cordyceps militaris (Hypocreales, Cordycipitaceae), on insect susceptibility to EPF infection and on insect immune gene expression. Application of the immune stimulant curdlan (20 µg ml-1, linear beta-1,3-glucan, a constituent of fungal cell walls) to Drosophila melanogaster S2r+ cells resulted in a significant increase in the expression of the immune effector gene metchnikowin compared to a DMSO-only control, but there was no significant increase when curdlan was co-applied with 25 µg ml-1 cordycepin dissolved in DMSO. Injection of cordycepin into larvae of Galleria mellonella (Lepidoptera: Pyralidae) resulted in dose-dependent mortality (LC50 of cordycepin = 2.1 mg per insect 6 days after treatment). Incubating conidia of C. militaris and Beauveria bassiana (Hypocreales, Cordycipitaceae; an EPF that does not synthesize cordycepin) with 3.0 mg ml-1 cordycepin had no effect on the numbers of conidia germinating in vitro. Co-injection of G. mellonella with a low concentration of cordycepin (3.0 mg ml-1) plus 10 or 100 conidia per insect of C. militaris or B. bassiana caused a significant decrease in insect median survival time compared to injection with the EPF on their own. Analysis of predicted vs. observed mortalities indicated a synergistic interaction between cordycepin and the EPF. The injection of C. militaris and B. bassiana into G. mellonella resulted in increased expression of the insect immune effector genes lysozyme, IMPI and gallerimycin at 72 h post injection, but this did not occur when the EPF were co-injected with 3.0 mg ml-1 cordycepin. In addition, we observed increased expression of IMPI and lysozyme at 48 h after injection with C. militaris, B. bassiana and sham injection (indicating a wounding response), but this was also prevented by application of cordycepin. These results suggest that cordycepin has potential to act as a suppressor of the immune response during fungal infection of insect hosts.


Assuntos
Agentes de Controle Biológico/farmacologia , Cordyceps/química , Desoxiadenosinas/farmacologia , Expressão Gênica/imunologia , Imunidade/genética , Mariposas/imunologia , Animais , Beauveria/química , Drosophila melanogaster/microbiologia , Larva/crescimento & desenvolvimento , Larva/imunologia , Larva/microbiologia , Mariposas/crescimento & desenvolvimento , Mariposas/microbiologia , Esporos Fúngicos/química
11.
mSphere ; 5(5)2020 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-32878933

RESUMO

Fungal chemodiversity is well known in part due to the production of diverse analogous compounds by a single biosynthetic gene cluster (BGC). Usually, similar or the same metabolites are produced by closely related fungal species under a given condition, the foundation of fungal chemotaxonomy. Here, we report a rare case of the production of the cyclodepsipeptide beauveriolides (BVDs) in three insect-pathogenic fungi. We found that the more closely related fungi Beauveria bassiana and Beauveria brongniartii produced structurally distinct analogs of BVDs, whereas the less-close relatives B. brongniartii and Cordyceps militaris biosynthesized structurally similar congeners under the same growth condition. It was verified that a conserved BGC containing four genes is responsible for BVD biosynthesis in three fungi, including a polyketide synthase (PKS) for the production of 3-hydroxy fatty acids (FAs) with chain length variations. In contrast to BVD production patterns, phylogenetic analysis of the BGC enzymes or enzyme domains largely resulted in the congruence relationship with fungal speciation. Feeding assays demonstrated that an FA with a chain length of eight carbon atoms was preferentially utilized, whereas an FA with a chain longer than 10 carbon atoms could not be used as a substrate for BVD biosynthesis. Insect survival assays suggested that the contribution of BVDs to fungal virulence might be associated with the susceptibility of insect species. The results of this study enrich the knowledge of fungal secondary metabolic diversity that can question the reliability of fungal chemotaxonomy.IMPORTANCE Fungal chemotaxonomy is an approach to classify fungi based on the fungal production profile of metabolites, especially the secondary metabolites. We found an atypical example that could question the reliability of fungal chemical classifications in this study, i.e., the more closely related entomopathogenic species Beauveria bassiana and Beauveria brongniartii produced structurally different congeners of the cyclodepsipeptide beauveriolides, whereas the rather divergent species B. brongniartii and Cordyceps militaris biosynthesized similar analogs under the same growth condition. The conserved biosynthetic gene cluster (BGC) containing four genes present in each species is responsible for beauveriolide production. In contrast to the compound formation profiles, the phylogenies of biosynthetic enzymes or enzymatic domains show associations with fungal speciation. Dependent on the insect species, production of beauveriolides may contribute to fungal virulence against the susceptible insect hosts. The findings in this study augment the diversity of fungal secondary metabolisms.


Assuntos
Beauveria/química , Depsipeptídeos/química , Proteínas Fúngicas/química , Animais , Beauveria/classificação , Vias Biossintéticas , Drosophila melanogaster , Feminino , Proteínas Fúngicas/classificação , Regulação Fúngica da Expressão Gênica , Larva/microbiologia , Mariposas/microbiologia , Família Multigênica , Filogenia , Virulência
12.
J Nat Prod ; 83(2): 296-304, 2020 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-32058711

RESUMO

We report NMR- and MS-based structural characterizations of siderophores and related compounds from Beauveria bassiana (Balsamo-Crivelli) Vuillemin, including ten new chemical entities (2-4, 6-9, 11-12, and 15) and five known compounds, (1, 5, 10, 13, and 14). The siderophore mixture from ARSEF strain #2680 included two compounds in which N5-mevalonyl-N5-hydroxyornithine replaces both (2) or one (3) of the N5-anhydromevalonyl-N5-hydroxyornithine units of dimerumic acid (1). Mevalonolactone (14) was present as a degradation product of 2 and 3. ARSEF #2860 also produced compounds that have mannopyranose (5, 6) or 4-O-methyl-mannopyranose units (4, 7), two compounds (8, 9) that can be rationalized as 4-O-methyl-mannopyranosyl analogues of the esterifying acid moieties of metachelins A and B, respectively, and two probable decomposition products of 1, a nitro compound (11) and a formate (12). Beauverichelin A (15), a coprogen-type siderophore that represents the di-4-O-methyl-mannopyranosyl analogue of metachelin A, was detected in crude extracts of ARSEF #2860, but only in trace amounts. ARSEF strains #252 and #1955 yielded beauverichelin A in quantities that were sufficient for NMR analysis. Only the di- (1-7) and trihydroxamate (15) siderophores showed iron-binding activity in the CAS assay and, when ferrated, showed strong ESIMS signals consistent with 1:1 ligand/iron complexes.


Assuntos
Beauveria/química , Sideróforos/química , Animais , Dicetopiperazinas/química , Ácidos Hidroxâmicos/química , Ferro/química , Ferro/metabolismo , Estrutura Molecular , Nitrocompostos/química , Sideróforos/isolamento & purificação
13.
Biotechnol Appl Biochem ; 67(3): 343-353, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31846537

RESUMO

R-2-(4-hydroxyphenoxy)propionicacid (HPOPA) is a valuable intermediate for the synthesis of enantiomerically pure aryloxyphenoxypropionic acid herbicides. In this work, to improve the HPOPA biosynthesis by Beauveria bassiana ZJB16002 from the substrate R-2-phenoxypropionic acid (POPA), the original HPOPA producer B. bassiana ZJB16002 was subjected to physical mutagenesis with 137 Cs-γ irradiation and chemical mutagen N-methyl-N'-nitro-N-nitrasoguanidine (NTG) induced mutagenesis. The effects of different treatment doses of the mutagens on the lethal rate and positive mutation rate were investigated, and the results showed that the optimal 137 Cs-γirradiation dose and NTG concentration was 850 Gy and 500 µg/mL, respectively. Under these conditions, a mutant strain CCN-7 with the highest HPOPA production capacity was obtained through two rounds of 137 Cs-γ irradiation treatment followed by one round of NTG mutagenesis. At the substrate (POPA) concentration of 50 g/L, HPOPA titer of CCN-7 reached 36.88 g/L, which was 9.73-fold higher than the parental strain. The morphology of the wild-type and mutant strain was compared and the results might provide helpful information in exploration of the correlation of morphology and biochemical features of B. bassiana.


Assuntos
Beauveria/genética , Beauveria/metabolismo , Propionatos/metabolismo , Beauveria/química , Estrutura Molecular , Éteres Fenílicos/química , Éteres Fenílicos/metabolismo , Propionatos/química , Estereoisomerismo
14.
Fungal Biol ; 123(8): 601-610, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31345414

RESUMO

Oosporein was first identified from the insect pathogen Beauveria bassiana >50 y ago. Here, we investigate the insecticidal, anti-feedant and immunomodulation effects of oosporein produced by Beauveria caledonica on the forestry pest Hylobius abietis and model insect Galleria mellonella. We report a novel feedback induction mechanism regulating oosporein production in B. caledonica; exogenous oosporein induces the expression of the oosporein cluster, leading to increased abundance of oosporein biosynthetic enzymes, as shown by label-free quantitative proteomics. Oosporein did not have an anti-feedant effect on H. abietis adults - on the contrary, insects exposed to oosporein-treated food fed more than those exposed to untreated food only. Injected oosporein did not kill insect larvae but increased susceptibility of H. abietis to a subsequent infection. Oosporein did not act as a contact toxin on H. abietis adults and G. mellonella larvae at the concentrations tested. Therefore, it appears that oosporein promotes infection rather than directly killing insects; this could be mediated both by a reduction in haemocyte numbers and by alterations to the humoral immune system. This work makes a case for future research into the potential use of B. caledonica as a biocontrol agent through combinations with oosporein or with enhanced production of oosporein.


Assuntos
Beauveria/metabolismo , Benzoquinonas/metabolismo , Benzoquinonas/toxicidade , Inseticidas/metabolismo , Inseticidas/toxicidade , Gorgulhos/microbiologia , Animais , Beauveria/química , Beauveria/patogenicidade , Vias Biossintéticas , Comportamento Alimentar/efeitos dos fármacos , Feminino , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Masculino , Virulência , Gorgulhos/fisiologia
15.
Sci Rep ; 9(1): 3171, 2019 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-30816211

RESUMO

Honeybee colonies are under the threat of many stressors, biotic and abiotic factors that strongly affect their survival. Recently, great attention has been directed at chemical pesticides, including their effects at sub-lethal doses on bee behaviour and colony success; whereas the potential side effects of natural biocides largely used in agriculture, such as entomopathogenic fungi, have received only marginal attention. Here, we report the impact of the fungus Beauveria bassiana on honeybee nestmate recognition ability, a crucial feature at the basis of colony integrity. We performed both behavioural assays by recording bee guards' response towards foragers (nestmate or non-nestmate) either exposed to B. bassiana or unexposed presented at the hive entrance, and GC-MS analyses of the cuticular hydrocarbons (CHCs) of fungus-exposed versus unexposed bees. Our results demonstrated that exposed bees have altered cuticular hydrocarbons and are more easily accepted into foreign colonies than controls. Since CHCs are the main recognition cues in social insects, changes in their composition appear to affect nestmate recognition ability at the colony level. The acceptance of chemically unrecognizable fungus-exposed foragers could therefore favour forager drift and disease spread across colonies.


Assuntos
Abelhas/fisiologia , Desinfetantes/metabolismo , Comportamento de Nidação/efeitos dos fármacos , Animais , Beauveria/química , Desinfetantes/química , Cromatografia Gasosa-Espectrometria de Massas , Comportamento de Nidação/fisiologia , Praguicidas/efeitos adversos
16.
J Appl Microbiol ; 126(1): 155-164, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30353989

RESUMO

AIM: To describe a new approach in which production of conidia of an entomopathogenic fungus takes place on the surface of an unstirred shallow liquid culture kept in nonabsorbent wells distributed in plastic sheets resembling a honeycomb. METHODS AND RESULTS: First, liquid incubation time and medium composition for production of Beauveria bassiana aerial conidia were optimized. Wells inoculated with Sabouraud dextrose yeast extract produced 2·2 × 108 conidia per cm2 of liquid surface following 5 days of incubation. Finally, tests were carried out in a prototype comprised of stacked plastic sheets in a cylindrical container. Conidia production on liquid culture surface varied from 1·2 to 1·6 × 109 conidia per ml of fermented broth. Germination rates and insect activity towards Tenebrio molitor larvae were not negatively affected when compared to conidia produced on solid medium. CONCLUSIONS: The two-stage fermentation process here described, based on a simple nonabsorbent inert support, has potential for the application in the production of aerial conidia of B. bassiana and other fungi. SIGNIFICANCE AND IMPACT OF THE STUDY: Aerial conidia are the most extensive propagule type used in commercial mycopesticides, traditionally produced by solid-state fermentation (SSF). The industrial applications and other important benefits of the two-stage fermentation process here described may overcome some hurdles inherent to SSF aiming for the production of aerial conidia. Additionally, production consistency is increased by the use of chemically defined medium, and the better control of the environmental conditions could allow for more reproducible industrial batches.


Assuntos
Beauveria/crescimento & desenvolvimento , Microbiologia Industrial/métodos , Esporos Fúngicos/crescimento & desenvolvimento , Animais , Beauveria/química , Beauveria/metabolismo , Meios de Cultura/química , Meios de Cultura/metabolismo , Fermentação , Microbiologia Industrial/instrumentação , Larva/microbiologia , Esporos Fúngicos/química , Esporos Fúngicos/metabolismo , Tensão Superficial , Tenebrio/microbiologia
17.
Molecules ; 23(10)2018 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-30297669

RESUMO

Pulmonary fibrosis (PF) is a chronic and fatal lung disease with few treatment options. Although the pathogenesis of PF is not clear, a chronic inflammatory response to continuous damage is considered the cause of pulmonary fibrosis. PF is characterized by excessive accumulation of extracellular matrix (ECM), therefore, inhibition of myofibroblast differentiation is a good therapeutic target for PF. As part of our continuing endeavor to explore biologically active metabolites from insect-associated microbes, we found that the MeOH extract of the culture broth from the entomopathogenic fungus Beauveria bassiana inhibited collagen induction and E-cadherin down-regulation. In order to identify active compounds, we carried out chemical analysis of the MeOH extract with the assistance of LC/MS-guided isolation approach, which led to the successful identification of four cyclodepsipeptides 1⁻4. Among the isolates, compound 2 showed inhibitory effects on myofibroblast differentiation induced by TGF-ß1. Compound 2 inhibited induction of α-SMA and N-cadherin, which are myofibroblast markers, and blocked the accumulation of ECM proteins such as collagen and fibronectin. Overall these findings demonstrate that compound 2 can be used to attenuate pulmonary fibrosis by targeting myo- fibroblast differentiation.


Assuntos
Beauveria/química , Diferenciação Celular/efeitos dos fármacos , Depsipeptídeos/farmacologia , Fibrose Pulmonar/tratamento farmacológico , Células A549 , Actinas/genética , Células Epiteliais Alveolares/efeitos dos fármacos , Caderinas/genética , Colágeno/genética , Depsipeptídeos/química , Depsipeptídeos/isolamento & purificação , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Humanos , Miofibroblastos/citologia , Miofibroblastos/efeitos dos fármacos , Fibrose Pulmonar/genética , Fator de Crescimento Transformador beta1/genética
18.
Sci Rep ; 8(1): 14958, 2018 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-30297846

RESUMO

Melanogenesis is the process of production of melanin pigments that are responsible for the colors of skin, eye, and hair and provide protection from ultraviolet radiation. However, excessive levels of melanin formation cause hyperpigmentation disorders such as freckles, melasma, and age spots. Liver X receptors (LXR) are nuclear oxysterol receptors belonging to the family of ligand-activated transcription factors and physiological regulators of lipid and cholesterol metabolism. In the skin, activation of LXRs stimulates differentiation of keratinocytes and augments lipid synthesis in sebocytes. However, the function of LXRs in melanogenesis has not been clearly elucidated. In addition, although beauvericin, a well-known mycotoxin primarily isolated from several fungi, has various biological properties, its involvement in melanogenesis has not been reported. Therefore, in this study, we examined the effects of beauvericin on melanogenesis and its molecular mechanisms. Beauvericin decreased melanin content and tyrosinase activity without any cytotoxicity. Beauvericin also reduced protein levels of MITF, tyrosinase, TRP1, and TRP2. In addition, beauvericin suppressed cAMP-PKA-CREB signaling and upregulated expression of LXR-α, resulting in the suppression of p38 MAPK. Our results indicate that beauvericin attenuates melanogenesis by regulating both cAMP/PKA/CREB and LXR-α/p38 MAPK pathways, consequently leading to a reduction of melanin levels.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Depsipeptídeos/farmacologia , Melaninas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Beauveria/química , Linhagem Celular Tumoral , AMP Cíclico/metabolismo , Depsipeptídeos/química , Humanos , Receptores X do Fígado/metabolismo , Melanócitos/efeitos dos fármacos , Melanócitos/metabolismo , Camundongos
19.
Insect Biochem Mol Biol ; 101: 1-13, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30026094

RESUMO

The large pine weevil Hylobius abietis L. is a major forestry pest in 15 European countries, where it is a threat to 3.4 million hectares of forest. A cellular and proteomic analysis of the effect of culture filtrate of three entomopathogenic fungi (EPF) species on the immune system of H. abietis was performed. Injection with Metarhizium brunneum or Beauvaria bassiana culture filtrate facilitated a significantly increased yeast cell proliferation in larvae. Larvae co-injected with either Beauvaria caledonica or B. bassiana culture filtrate and Candida albicans showed significantly increased mortality. Together these results suggest that EPF culture filtrate has the potential to modulate the insect immune system allowing a subsequent pathogen to proliferate. Injection with EPF culture filtrate was shown to alter the abundance of protease inhibitors, detoxifing enzymes, antimicrobial peptides and proteins involved in reception/detection and development in H. abietis larvae. Larvae injected with B. caledonica culture filtrate displayed significant alterations in abundance of proteins involved in cellulolytic and other metabolic processes in their haemolymph proteome. Screening EPF for their ability to modulate the insect immune response represents a means of assessing EPF for use as biocontrol agents, particularly if the goal is to use them in combination with other control agents.


Assuntos
Peptídeos Catiônicos Antimicrobianos/imunologia , Hemolinfa/imunologia , Proteínas de Insetos/imunologia , Larva/imunologia , Inibidores de Proteases/imunologia , Proteoma/imunologia , Animais , Peptídeos Catiônicos Antimicrobianos/genética , Peptídeos Catiônicos Antimicrobianos/isolamento & purificação , Beauveria/química , Beauveria/metabolismo , Beauveria/patogenicidade , Candida albicans/química , Candida albicans/metabolismo , Candida albicans/patogenicidade , Meios de Cultivo Condicionados/farmacologia , Filtração , Expressão Gênica , Hemolinfa/química , Hemolinfa/metabolismo , Hemolinfa/microbiologia , Proteínas de Insetos/genética , Proteínas de Insetos/isolamento & purificação , Larva/genética , Larva/microbiologia , Metarhizium/química , Metarhizium/metabolismo , Metarhizium/patogenicidade , Microinjeções , Controle Biológico de Vetores/métodos , Pinus/parasitologia , Inibidores de Proteases/isolamento & purificação , Inibidores de Proteases/metabolismo , Proteoma/genética , Proteoma/isolamento & purificação , Proteômica/métodos , Gorgulhos/genética , Gorgulhos/imunologia , Gorgulhos/microbiologia
20.
J Vis Exp ; (133)2018 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-29608152

RESUMO

Coffee berry borer (CBB) is the most devastating insect pest for coffee crops worldwide. We developed a scientific monitoring protocol that is aimed at capturing and quantifying the dynamics and impact of this invasive insect pest as well as the development of its host plant across a heterogeneous landscape. The cornerstone of this comprehensive monitoring system is timely georeferenced data collection on CBB movement, coffee berry infestation, mortality by the fungus Beauveria bassiana, and coffee plant phenology via a mobile electronic data recording application. This electronic data collection system allows field records to be georeferenced through built-in global positioning systems, and is backed by a network of weather stations and records of farm management practices. Comprehensive monitoring of CBB and host plant dynamics is an essential part of an area-wide project in Hawaii to aggregate landscape-level data for research to improve management practices. Coffee agroecosystems in other parts of the world that experience highly variable environmental and socioeconomic factors will also benefit from implementing this protocol, in that it will drive the development of customized integrated pest management (IPM) to manage CBB populations.


Assuntos
Beauveria/química , Café/crescimento & desenvolvimento , Ecossistema , Agricultura , Animais , Café/química , Café/microbiologia , Havaí
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