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1.
Nat Prod Res ; 36(18): 4605-4613, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34736358

RESUMO

Four new depsidones, mollicellins V-Y (1-4), together with eight known depsidones (5-12) were isolated from the endophytic fungus, Chaetomium brasiliense, detached from stems of Thai rice. Their structures were determined by extensive spectroscopic methods. Mollicellins X, H, and F (3, 8 and 10) showed potent cytotoxicity against the human oral epidermoid carcinoma (KB) cell line, and mollicellin F (10) also showed a potent cytotoxicity against the human hepatocellular carcinoma (HepG2) cell line. Besides, mollicellin B (11) exhibited cytotoxicity against the colorectal adenocarcinoma (HT-29) cell line. Moreover, most of the isolated depsidones displayed potent antibacterial activity against Gram-positive bacteria, Bacillus cereus and Bacillus subtilis, and several of them showed moderate activity against Methicillin-resistant Staphylococcus aureus (MRSA) and clinical isolates of S. aureus. In addition, a few of them also showed moderate activity against a Gram-negative bacteria Pseudomonas aeruginosa.


Assuntos
Antineoplásicos , Chaetomium , Staphylococcus aureus Resistente à Meticilina , Oryza , Antibacterianos/química , Antineoplásicos/química , Chaetomium/química , Depsídeos , Humanos , Lactonas , Testes de Sensibilidade Microbiana , Estrutura Molecular , Sordariales , Staphylococcus aureus , Tailândia
2.
Am J Trop Med Hyg ; 106(2): 574-577, 2021 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-34814109

RESUMO

Chaetomium sp. is a mold, member of the phylum Ascomycota. Clinical disease in humans is rare, particularly in children, for which only five cases have been reported. We report a 7-months-old female patient with a diagnosis of visceral heterotaxy syndrome who was admitted to a private center in Mexico. After two episodes of focal myoclonic seizure, a brain magnetic resonance imaging (MRI) revealed a right porencephalic cyst and a right frontal abscess with ventriculitis. Seventy-two hours after temporal abscesses drainage procedure, the culture showed a rapidly growing pale white fungal colony. Sequencing of internal transcribed spacer (ITS) and D1/D2 led to the identification of Chaetomium strumarium. Although Chaetomium sp. is a rare fungal infection in humans, clinicians should consider it as a plausible etiologic agent that can form brain abscess.


Assuntos
Feoifomicose Cerebral/diagnóstico por imagem , Chaetomium/patogenicidade , Síndrome de Heterotaxia/complicações , Micoses/diagnóstico por imagem , Antifúngicos/uso terapêutico , Encéfalo/diagnóstico por imagem , Chaetomium/genética , Feminino , Síndrome de Heterotaxia/microbiologia , Humanos , Lactente , Imageamento por Ressonância Magnética , México , Micoses/tratamento farmacológico
3.
Int J Food Microbiol ; 357: 109383, 2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34509931

RESUMO

In food industries UV-C irradiation is used to achieve decontamination of some packaging devices, such as plastic caps or laminated foils, and of those smooth surfaces that can be directly irradiated. Since its effectiveness can be checked by microbial validation tests, some ascospore-forming molds (Aspergillus hiratsukae, Talaromyces bacillisporus, Aspergillus montevidensis, and Chaetomium globosum) were compared with one of the target microorganisms actually used in industrial bio-validations (Aspergillus brasiliensis ATCC 16404) to find the species most resistant to UV-C. Tests were carried out with an UV-C lamp (irradiance = 127 µW/cm2; emission peak = 253.7 nm) by inoculating HDPE caps with one or more layers of spores. Inactivation kinetics of each strain were studied and both the corresponding 1D-values and the number of Logarithmic Count Reductions (LCR) achieved were calculated. Our results showed the important role played by the type of inoculum (one or more layers) and by the differences in cell structure (thickness, presence of protective solutes, pigmentation, etc.) of the strains tested. With a single-layer inoculum, Chaetomium globosum showed the highest resistance to UV-C irradiation (1D-value = 100 s). With a multi-layer inoculum, Aspergillus brasiliensis ATCC 16404 was the most resistant fungus (1D-value = 188 s), even if it reached a number of logarithmic reductions that was higher than those of some ascospore-forming mycetes (Aspergillus montevidensis, Talaromyces bacillisporus) tested.


Assuntos
Embalagem de Alimentos , Talaromyces , Aspergillus , Chaetomium , Esterilização
4.
Prensa méd. argent ; 105(5): 302-308, jun 2019. fig, tab
Artigo em Inglês | LILACS, BINACIS | ID: biblio-1024638

RESUMO

Aim: The current venture, were made to evaluate the inhibitory effect of Trigonella foenum seed Extract and ZiO2 Nanoparticles on some selected species of Fungi and Bacteria. Materials and Methods: two bacterial species included Pseudomonas aeruginosa and Staphylococcus aureus and three fungal species which is Cryptococcus neoformans, Candidda albicans and Chaetomium were used to evaluate the antibacterial activity of Trigonella foenum Extract and ZiO2 Nanoparticles. Results: This study showed that the Zirconium Oxide (ZiO2) nanoparticles have antifungal and antibacterial activities on the isolates of Cryptococcus neoformans, Candida alicans and Staphylococcus aureus, respectively. While the antimicrobial activity of Zirconium Oxide nanoparticles on the Chaetomium and Pseudomonas aeruginosa was negative. All tested fungi and bacterial isolates were found to be sensitive to Trigonella foenum seed extract, the results of the compination of the ZiO2 Nanoparticle and the Trigonella foenum seed extract were poisitive for all tested fungi isolates and bacterial isolates. The XRD analysis was done for Zirconium Oxide nanoparticles and the result showed that the biocrystallization on the surface of the Zirconium Oxide manoparticles. The average partides size was about (29.8) nm. Conclusions: This investigation conclude that the use of Trigonella foenum seed Extract has the effect of killing all bacteria and fungi under study, result indicate the Trigonella foenun seed Extract best antibacterial efficacy than the ZiO2 together (AU)


Assuntos
Humanos , Pseudomonas aeruginosa/patogenicidade , Staphylococcus aureus/patogenicidade , Candida albicans/patogenicidade , Chaetomium/patogenicidade , Cryptococcus neoformans/patogenicidade , Trigonella/microbiologia , Nanopartículas/efeitos adversos , Fabaceae/efeitos adversos , Anti-Infecciosos/uso terapêutico , Antibacterianos/uso terapêutico , Antifúngicos/uso terapêutico
5.
Folia Microbiol (Praha) ; 64(1): 1-7, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29882027

RESUMO

The increasing use of plastics in human activities has resulted in an enormous amount of residues which became a matter of great environmental concern. Scientific studies on the microbial degradation of natural and synthetic molecules show the potential of fungal application on cleaning technologies. The biodegradation of PCL (polycaprolactone) and PVC (polyvinyl chloride) films by Aspergillus brasiliensis (ATCC 9642), Penicillium funiculosum (ATCC 11797), Chaetomium globosum (ATCC 16021), Trichoderma virens (ATCC 9645), and Paecilomyces variotii (ATCC 16023) was studied. According to ISO 846-1978-"Testing of Plastics - Influence of fungi and bacteria", samples of the studied polymers were inoculated with a mix suspension of 106 fungal inoculum and maintained in moisture glass chambers in a bacteriological incubator at 28 °C for 28 days. The samples were analyzed by means of morphological and color changes, mass loss, optical microscopy (OM), and scanning electron microscopy (SEM) after 28 days of culturing. After the incubation period, visual observations of the PCL films showed many micropores and cracks, pigmentation, surface erosion and hyphal adhesion on the sample surfaces, and a mass loss of up to 75%. On the contrary, there was no evidence of PVC biodegradation, such as changes in color and significant mass loss. Chaetomium globosum ATCC 16021 was a pioneer in the colonization and attack of PCL, resulting in significant mass losses. Although PVC was less attacked by the ascomycete, the polymer supported the adhesion and growth of its fertile structures (perithecia), suggesting the fungal potential to degrade both plastics.


Assuntos
Chaetomium/metabolismo , Poliésteres/metabolismo , Cloreto de Polivinila/metabolismo , Biodegradação Ambiental , Chaetomium/crescimento & desenvolvimento , Fungos/metabolismo , Hifas/crescimento & desenvolvimento , Hifas/metabolismo
6.
Braz. J. Microbiol. ; 48(3): 410-418, jul.-set. 2017. graf, tab
Artigo em Inglês | VETINDEX | ID: vti-728605

RESUMO

Chaetoglobosin A is an antibacterial compound produced by Chaetomium globosum, with potential application as a biopesticide and cancer treatment drug. The aim of this study was to evaluate the feasibility of utilizing cornstalks to produce chaetoglobosin A by C. globosum W7 in solid-batch fermentation and to determine an optimal method for purification of the products. The output of chaetoglobosin A from the cornstalks was 0.34 mg/g, and its content in the crude extract was 4.80%. Purification conditions were optimized to increase the content of chaetoglobosin A in the crude extract, including the extract solvent, temperature, and pH value. The optimum process conditions were found to be acetone as the extractant, under room temperature, and at a pH value of 13. Under these conditions, a production process of the antifungal chaetoglobosin A was established, and the content reached 19.17%. Through further verification, cornstalks could replace crops for the production of chaetoglobosin A using this new production process. Moreover, the purified products showed great inhibition against Rhizoctonia solani, with chaetoglobosin A confirmed as the main effective constituent (IC50 = 3.88 µg/mL). Collectively, these results demonstrate the feasibility of using cornstalks to synthesize chaetoglobosin A and that the production process established in this study was effective.(AU)


Assuntos
Chaetomium , Zea mays , Antifúngicos/análise , Uso de Resíduos Sólidos , Antibacterianos
7.
Braz. j. microbiol ; 48(3): 410-418, July-Sept. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-889127

RESUMO

Abstract Chaetoglobosin A is an antibacterial compound produced by Chaetomium globosum, with potential application as a biopesticide and cancer treatment drug. The aim of this study was to evaluate the feasibility of utilizing cornstalks to produce chaetoglobosin A by C. globosum W7 in solid-batch fermentation and to determine an optimal method for purification of the products. The output of chaetoglobosin A from the cornstalks was 0.34 mg/g, and its content in the crude extract was 4.80%. Purification conditions were optimized to increase the content of chaetoglobosin A in the crude extract, including the extract solvent, temperature, and pH value. The optimum process conditions were found to be acetone as the extractant, under room temperature, and at a pH value of 13. Under these conditions, a production process of the antifungal chaetoglobosin A was established, and the content reached 19.17%. Through further verification, cornstalks could replace crops for the production of chaetoglobosin A using this new production process. Moreover, the purified products showed great inhibition against Rhizoctonia solani, with chaetoglobosin A confirmed as the main effective constituent (IC50 = 3.88 µg/mL). Collectively, these results demonstrate the feasibility of using cornstalks to synthesize chaetoglobosin A and that the production process established in this study was effective.


Assuntos
Microbiologia Industrial/métodos , Calosidades/microbiologia , Chaetomium/metabolismo , Alcaloides Indólicos/metabolismo , Antifúngicos/metabolismo , Resíduos/análise , Microbiologia Industrial/instrumentação , Calosidades/metabolismo , Estrutura Molecular , Caules de Planta/metabolismo , Caules de Planta/microbiologia , Alcaloides Indólicos/isolamento & purificação , Alcaloides Indólicos/química , Antifúngicos/isolamento & purificação , Antifúngicos/química
8.
Braz J Microbiol ; 48(3): 410-418, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28223029

RESUMO

Chaetoglobosin A is an antibacterial compound produced by Chaetomium globosum, with potential application as a biopesticide and cancer treatment drug. The aim of this study was to evaluate the feasibility of utilizing cornstalks to produce chaetoglobosin A by C. globosum W7 in solid-batch fermentation and to determine an optimal method for purification of the products. The output of chaetoglobosin A from the cornstalks was 0.34mg/g, and its content in the crude extract was 4.80%. Purification conditions were optimized to increase the content of chaetoglobosin A in the crude extract, including the extract solvent, temperature, and pH value. The optimum process conditions were found to be acetone as the extractant, under room temperature, and at a pH value of 13. Under these conditions, a production process of the antifungal chaetoglobosin A was established, and the content reached 19.17%. Through further verification, cornstalks could replace crops for the production of chaetoglobosin A using this new production process. Moreover, the purified products showed great inhibition against Rhizoctonia solani, with chaetoglobosin A confirmed as the main effective constituent (IC50=3.88µg/mL). Collectively, these results demonstrate the feasibility of using cornstalks to synthesize chaetoglobosin A and that the production process established in this study was effective.


Assuntos
Antifúngicos/metabolismo , Calosidades/microbiologia , Chaetomium/metabolismo , Alcaloides Indólicos/metabolismo , Microbiologia Industrial/métodos , Antifúngicos/química , Antifúngicos/isolamento & purificação , Calosidades/metabolismo , Alcaloides Indólicos/química , Alcaloides Indólicos/isolamento & purificação , Microbiologia Industrial/instrumentação , Estrutura Molecular , Caules de Planta/metabolismo , Caules de Planta/microbiologia , Resíduos/análise
9.
Braz. j. microbiol ; 47(2): 480-488, Apr.-June 2016. tab, graf
Artigo em Inglês | LILACS | ID: lil-780842

RESUMO

Abstract The aim of this paper is to identify and investigate an endophytic fungus (strain 28) that was isolated from Houttuynia cordata Thunb, a famous and widely-used Traditional Chinese Medicine. Based on morphological methods and a phylogenetic analysis of ITS sequences, this strain was identified as Chaetomium globosum. An antifungal activity bioassay demonstrated that the crude ethyl acetate (EtOAc) extracts of strain 28 had a wide antifungal spectrum and strong antimicrobial activity, particularly against Exserohilum turcicum (Pass.) Leonard et Suggs, Botrytis cinerea persoon and Botrytis cinerea Pers. ex Fr. Furthermore, the fermentation conditions, extraction method and the heat stability of antifungal substances from strain 28 were also studied. The results showed that optimal antifungal activity can be obtained with the following parameters: using potato dextrose broth (PDB) as the base culture medium, fermentation for 4–8 d (initial pH: 7.5), followed by extraction with EtOAc. The extract was stable at temperatures up to 80 °C. This is the first report on the isolation of endophytic C. globosum from H. cordata to identify potential alternative biocontrol agents that could provide new opportunities for practical applications involving H. cordata.


Assuntos
Chaetomium/isolamento & purificação , Chaetomium/metabolismo , Houttuynia/microbiologia , Endófitos/metabolismo , Antifúngicos/metabolismo , Filogenia , Chaetomium/classificação , Chaetomium/genética , Endófitos/isolamento & purificação , Endófitos/classificação , Endófitos/genética , Fungos/crescimento & desenvolvimento , Fungos/efeitos dos fármacos , Antifúngicos/farmacologia
10.
Braz. J. Microbiol. ; 47(2): 480-488, Abr-Jun. 2016. ilus, tab
Artigo em Inglês | VETINDEX | ID: vti-23440

RESUMO

The aim of this paper is to identify and investigate an endophytic fungus (strain 28) that was isolated from Houttuynia cordata Thunb, a famous and widely-used Traditional Chinese Medicine. Based on morphological methods and a phylogenetic analysis of ITS sequences, this strain was identified as Chaetomium globosum. An antifungal activity bioassay demonstrated that the crude ethyl acetate (EtOAc) extracts of strain 28 had a wide antifungal spectrum and strong antimicrobial activity, particularly against Exserohilum turcicum (Pass.) Leonard et Suggs, Botrytis cinerea persoon and Botrytis cinerea Pers. ex Fr. Furthermore, the fermentation conditions, extraction method and the heat stability of antifungal substances from strain 28 were also studied. The results showed that optimal antifungal activity can be obtained with the following parameters: using potato dextrose broth (PDB) as the base culture medium, fermentation for 48 d (initial pH: 7.5), followed by extraction with EtOAc. The extract was stable at temperatures up to 80 °C. This is the first report on the isolation of endophytic C. globosum from H. cordata to identify potential alternative biocontrol agents that could provide new opportunities for practical applications involving H. cordata.(AU)


Assuntos
Houttuynia/microbiologia , Chaetomium/isolamento & purificação , Antifúngicos/análise , Acetatos/análise , Bioensaio
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