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Arch Microbiol ; 203(6): 3415-3423, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33891129


In a first step, essential oils were extracted from Eucalyptus globulus leaves, healthy and with symptoms and signs of Mycosphaerella leaf disease (MLD) and Teratosphaeria leaf disease (TLD), in two leaf stages. Stage 1: sessile, oval leaves covered by a waxy layer of a bluish colour, with opposite phyllotaxis, inserted along stems of quadrangular section. Stage 2: narrow and sickle leaves with a greyish green surface, mainly on the abaxial surface, inserted in alternating pairs along rounded stems. The essential oils were extracted by hydrodistillation and were analyzed by gas chromatography coupled with mass spectrometry. Chemical composition data and percentages of essential oil constituents were submitted to cluster analysis and principal component analysis. In a second step, under in vitro conditions, was evaluated the germination of Teratosphaeria nubilosa (one of the causal agents of TLD) ascospores in contact with the four types of essential oils extracted. The evaluations were performed at 24, 48 and 72 h after the experiments were assembled. The present study made it possible to distinguish and identify the chemical composition of essential oils from the eucalypt leaves used, and allowed 1,8-cineole to be identified as the major component for the essential oils investigated. The contact between essential oils and T. nubilosa spores allowed to prove the inhibition of the ascospores germination, being more efficient for the essential oils extracted from materials with the disease, which presented high amounts of 1,8-cineole.

Ascomicetos , Eucalyptus , Mycosphaerella , Óleos Voláteis , Esporos Fúngicos , Ascomicetos/fisiologia , Eucalyptus/microbiologia , Mycosphaerella/fisiologia , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Folhas de Planta/microbiologia , Esporos Fúngicos/efeitos dos fármacos
Neurogastroenterol Motil ; 32(11): e13891, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32449259


BACKGROUND: Little is known about intestinal fungi in IBS patients whose gut bacteria have been investigated a lot. In order to explore causal relationship between IBS and gut mycobiome, and use gut fungi to diagnose or even treat IBS, further characterization of it in IBS is required. METHODS: Fifty-five diarrhea-predominant IBS (D-IBS) patients fulfilling Rome III criteria, and 16 healthy controls (HC) were recruited. Fresh fecal samples were collected and used for 16s rRNA and ITS2 high-throughput sequencing. Diversity and composition of gut bacteria and fungi, as well as bacterial-fungal interactions in D-IBS patients, were characterized. Specific fungal taxa differentiating D-IBS from HC were recognized by LEfSe and RandomForest methods, and their association with clinical symptoms was assessed by Spearman's correlation. RESULTS: Diarrhea-predominant irritable bowel syndrome patients showed abnormal (IBS-dysbiosis) or normal (HC-like IBS) fecal bacterial structure and diversity compared with healthy controls. However, fecal fungal signatures differed absolutely between D-IBS and HC, which indicated a more susceptible alteration of gut fungi than bacteria in D-IBS. Fecal fungi showed significant correlations with IBS symptoms, especially Mycosphaerella, Aspergillus, Sporidiobolus, and Pandora which were identified to potentially differentiate D-IBS from HC. Moreover, compared with HC there were markedly declined bacterial-fungal interactions in D-IBS, in which Candida changed from negative to positive correlations with bacteria, and Eurotium changed from positive correlations to irrelevance, while Debaryomyces gained negative correlations with bacteria. CONCLUSIONS: Gut fungal dysbiosis and altered bacterial-fungal interactions were present in patients with D-IBS, and gut fungi could be used to diagnose D-IBS.

Bactérias/genética , Diarreia/microbiologia , Disbiose/microbiologia , Microbioma Gastrointestinal/genética , Síndrome do Intestino Irritável/microbiologia , Interações Microbianas , Micobioma/genética , Adulto , Aspergillus , Basidiomycota , Candida , Estudos de Casos e Controles , DNA Espaçador Ribossômico/genética , Debaryomyces , Diarreia/fisiopatologia , Entomophthorales , Eurotium , Feminino , Fungos , Humanos , Síndrome do Intestino Irritável/fisiopatologia , Masculino , Pessoa de Meia-Idade , Mycosphaerella , RNA Ribossômico 16S/genética
Chin J Nat Med ; 18(4): 243-249, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32402399


Mycosphazine A (1), a new iron(III) chelator of coprogen-type siderophore, and mycosphamide A (2), a new cyclic amide benzoate, together with six known aryl amides (3-8), were isolated from the fermentation broth of the deep-sea-derived fungus Mycosphaerella sp. SCSIO z059. Alkaline hydrolysis of 1 afforded a new epimer of dimerum acid, mycosphazine B (1a), and a new bi-fusarinine-type siderophore, mycosphazine C (1b). The planar structures of the new compounds were elucidated by extensive spectroscopic data analysis. The absolute configurations of amino acid residues in 1a and 1b were determined by acid hydrolysis. And the absolute configuration of 2 was established by quantum chemical calculations of the electronic circular dichroism (ECD) spectra. Compound 1 is the first siderophore-Fe(III) chelator incorporating both L-ornithine and D-ornithine unites. Compounds 3-8 were reported as natural products for the first time, and the 1H and 13C NMR data of 6 and 8 were assigned for the first time. Compounds 1 and 1a could greatly promote the biofilm formation of bacterium Bacillus amyloliquefaciens with the rate of about 249% and 524% at concentration of 100 µg·mL-1, respectively.

Ácidos Hidroxâmicos/metabolismo , Ferro/metabolismo , Mycosphaerella/metabolismo , Sideróforos/metabolismo , Organismos Aquáticos , Ácidos Hidroxâmicos/química , Ferro/química , Estrutura Molecular , Mycosphaerella/química , Sideróforos/química