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1.
Ecotoxicol Environ Saf ; 188: 109935, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31740233

RESUMO

Chromium (Cr) is one of the most toxic heavy metals and a health hazard to millions of people worldwide. Ectomycorrhizal (ECM) fungi can assist plants in phytoremediation of heavy metal contaminated soil. Cr tolerance differs among ECM fungal varieties, but the underlying molecular mechanisms of Cr tolerance in ECM fungi are not clear. This study identified, analysed and compared the Cr(VI)-induced transcriptional changes between Cr(VI)-tolerant strain (Pisolithus sp. 1 LS-2017) and Cr(VI)-sensitive strain (Pisolithus sp. 2 LS-2017) by de novo transcriptomic analysis. The results showed that 93,642 assembled unique transcripts representing the 22,353 (46.76%) unigenes matched the proteins we have known in the Nr database and 47,801 unigenes were got from the Pisolithus spp. For DEGs between the control and 10 mg/L Cr(VI) treatment, cyanoamino acid metabolic, type I diabetes mellitus metabolism, nitrogen metabolism and beta-Alanine metabolism pathways were significantly enriched (p < 0.05) in Pisolithus sp. 1 LS-2017. Two nitrate reductase family genes (nidD, niiA) provide Cr(VI) tolerance for Pisolithus sp. 1 LS-2017 by regulating Cr(VI) reduction. In addition, NO produced by nidD, niiA regulated denitrification can alleviate Cr(VI) induced oxidative stress. In Pisolithus sp. 2 LS-2017, the alcC, aldA and lcf2 gene may alleviate Cr(VI) induced oxidative stress by protecting SH groups and increasing secondary metabolism, reducing detoxify aldehydes to carboxylic acids and producing LCPUFAs respectively; .T gene regulate Cr(VI) induced wound healing by pigmentation and stability of melanin in spore; MKP2 gene accelerate Cr(VI) induced cell death and gpmA gene regulated Cr(VI) induced energy emergency.


Assuntos
Basidiomycota/genética , Cromo/toxicidade , Genes Fúngicos , Micorrizas/genética , Poluentes do Solo/toxicidade , Transcriptoma/efeitos dos fármacos , Adaptação Fisiológica , Basidiomycota/metabolismo , Biodegradação Ambiental , Desnitrificação , Perfilação da Expressão Gênica , Micorrizas/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/genética , Solo/química , Microbiologia do Solo/normas
2.
Ecotoxicol Environ Saf ; 186: 109741, 2019 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-31600651

RESUMO

Piriformospora indica is known for plant growth promotion and abiotic stress alleviation potential in several agricultural crops. However, a systemic analysis is warranted to explore potential application of this important fungus to augment heavy metal tolerance in rice. The present study explores potential of P. indica in ameliorating the effect of cadmium (Cd) stress in rice cultivars N22 and IR64. Seedlings inoculated with P. indica recorded significantly higher root-shoot length and biomass as compared to non-inoculated plants under control and Cd stress, respectively. Moreover, P. indica inoculated stressed roots accumulated more Cd as compared to non-inoculated stressed roots in both the varieties. Interestingly, cell death and reactive oxygen species (ROS) accumulation were significantly lower in the inoculated plant roots as compare with non-inoculated roots under Cd stress. The results emphasized significantly higher accumulation of Cd in fungal spores could reduce ROS accumulation in root cells resulting in lower cell death.


Assuntos
Basidiomycota/fisiologia , Cádmio/toxicidade , Oryza/microbiologia , Estresse Oxidativo , Raízes de Plantas/microbiologia , Basidiomycota/metabolismo , Biomassa , Cádmio/metabolismo , Morte Celular/efeitos dos fármacos , Oryza/efeitos dos fármacos , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Plântula/crescimento & desenvolvimento , Plântula/metabolismo
3.
Int J Mol Sci ; 20(18)2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31487924

RESUMO

Chaga (Inonotus obliquus) is a medicinal fungus used in traditional medicine of Native American and North Eurasian cultures. Several studies have demonstrated the medicinal properties of chaga's bioactive molecules. For example, several terpenoids (e.g., betulin, betulinic acid and inotodiol) isolated from I. obliquus cells have proven effectiveness in treating different types of tumor cells. However, the molecular mechanisms and regulation underlying the biosynthesis of chaga terpenoids remain unknown. In this study, we report on the optimization of growing conditions for cultured I. obliquus in presence of different betulin sources (e.g., betulin or white birch bark). It was found that better results were obtained for a liquid culture pH 6.2 at 28 °C. In addition, a de novo assembly and characterization of I. obliquus transcriptome in these growth conditions using Illumina technology was performed. A total of 219,288,500 clean reads were generated, allowing for the identification of 20,072 transcripts of I. obliquus including transcripts involved in terpenoid biosynthesis. The differential expression of these genes was confirmed by quantitative-PCR. This study provides new insights on the molecular mechanisms and regulation of I. obliquus terpenoid production. It also contributes useful molecular resources for gene prediction or the development of biotechnologies for the alternative production of terpenoids.


Assuntos
Basidiomycota/genética , Genes Fúngicos , Transcriptoma , Triterpenos/metabolismo , Basidiomycota/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica
4.
Appl Microbiol Biotechnol ; 103(19): 8145-8155, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31482283

RESUMO

The environmental accumulation of polycyclic aromatic hydrocarbons (PAHs) is of great concern due to potential carcinogenic and mutagenic risks, as well as their resistance to remediation. While many fungi have been reported to break down PAHs in environments, the details of gene-based metabolic pathways are not yet comprehensively understood. Specifically, the genome-scale transcriptional responses of fungal PAH degradation have rarely been reported. In this study, we report the genomic and transcriptomic basis of PAH bioremediation by a potent fungal degrader, Dentipellis sp. KUC8613. The genome size of this fungus was 36.71 Mbp long encoding 14,320 putative protein-coding genes. The strain efficiently removed more than 90% of 100 mg/l concentration of PAHs within 10 days. The genomic and transcriptomic analysis of this white rot fungus highlights that the strain primarily utilized non-ligninolytic enzymes to remove various PAHs, rather than typical ligninolytic enzymes known for playing important roles in PAH degradation. PAH removal by non-ligninolytic enzymes was initiated by both different PAH-specific and common upregulation of P450s, followed by downstream PAH-transforming enzymes such as epoxide hydrolases, dehydrogenases, FAD-dependent monooxygenases, dioxygenases, and glycosyl- or glutathione transferases. Among the various PAHs, phenanthrene induced a more dynamic transcriptomic response possibly due to its greater cytotoxicity, leading to highly upregulated genes involved in the translocation of PAHs, a defense system against reactive oxygen species, and ATP synthesis. Our genomic and transcriptomic data provide a foundation of understanding regarding the mycoremediation of PAHs and the application of this strain for polluted environments.


Assuntos
Basidiomycota/genética , Basidiomycota/metabolismo , Perfilação da Expressão Gênica , Genômica , Redes e Vias Metabólicas/genética , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Biotransformação
5.
J Basic Microbiol ; 59(10): 1016-1030, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31430397

RESUMO

Heavy metals such as lead, chromium, and metalloid like arsenic dominate the pinnacle in posing a threat to life. Being environment-friendly, elucidating the mechanism by which microorganisms detoxify such elements has always been an active field of research hitherto. In the present study, we have investigated the capability of nitrogen-deprived Papiliotrema laurentii strain RY1 toward enhanced tolerance and neutralizing toxic elements. There were biosorption and bioprecipitation of lead and chromium at the cell surfaces. Bioprecipitation mechanisms included the formation of lead phosphates and pyromorphites from lead, grimaldite from chromium. Transcripts such as metallothionein, aquaporins, and arsenical pump-driving ATPase have been surmised to be involved in the detoxification of elements. Furthermore, activation of antioxidant defense mechanisms for the cells for each of the elements should contribute towards yeast's propagation. The efficiency of removal of elements for live cells and immobilized cells were high for lead and chromium. To the best of our knowledge, this is the first report of such high tolerance of lead, arsenic, and chromium for any yeast. The yeast showed such varied response under dual stress due to nitrogen starvation and in the presence of respective elements. The yeast possesses promising potentials in nitrogen deprived and enriched environments to aid in bioremediation sectors.


Assuntos
Arsênico/metabolismo , Basidiomycota/metabolismo , Poluentes Ambientais/metabolismo , Metais Pesados/metabolismo , Nitrogênio/metabolismo , Antioxidantes/metabolismo , Arsênico/toxicidade , Basidiomycota/efeitos dos fármacos , Basidiomycota/crescimento & desenvolvimento , Biodegradação Ambiental , Transporte Biológico/genética , Cádmio/metabolismo , Cádmio/toxicidade , Poluentes Ambientais/toxicidade , Expressão Gênica , Inativação Metabólica , Chumbo/metabolismo , Chumbo/toxicidade , Metalotioneína/genética , Metais Pesados/toxicidade , Testes de Sensibilidade Microbiana
6.
Enzyme Microb Technol ; 130: 109370, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31421724

RESUMO

Secretome evaluations of lignocellulose-decay basidiomycetes can reveal new enzymes in selected fungal species that degrade specific substrates. Proteins discovered in such studies can support biorefinery development. Brown-rot (Gloeophyllum trabeum) and white-rot (Pleurotus ostreatus) fungi growing in sugarcane bagasse solid-state cultures produced 119 and 63 different extracellular proteins, respectively. Several of the identified enzymes are suitable for in vitro biomass conversion, including a range of cellulases (endoglucanases, cellobiohydrolases and ß-glucosidases), hemicellulases (endoxylanases, α-arabinofuranosidases, α-glucuronidases and acetylxylan esterases) and carbohydrate-active auxiliary proteins, such as AA9 lytic polysaccharide monooxygenase, AA1 laccase and AA2 versatile peroxidase. Extracellular oxalate decarboxylase was also detected in both fungal species, exclusively in media containing sugarcane bagasse. Interestingly, intracellular AA6 quinone oxidoreductases were also exclusively produced under sugarcane bagasse induction in both fungi. These enzymes promote quinone redox cycling, which is used to produce Fenton's reagents by lignocellulose-decay fungi. Hitherto undiscovered hypothetical proteins that are predicted in lignocellulose-decay fungi genomes appeared in high relative abundance in the cultures containing sugarcane bagasse, which suggests undisclosed, new biochemical mechanisms that are used by lignocellulose-decay fungi to degrade sugarcane biomass. In general, lignocellulose-decay fungi produce a number of canonical hydrolases, as well as some newly observed enzymes, that are suitable for in vitro biomass digestion in a biorefinery context.


Assuntos
Basidiomycota/metabolismo , Celulose/metabolismo , Lignina/metabolismo , Metaboloma , Pleurotus/metabolismo , Saccharum/metabolismo , Biomassa , Celulases/metabolismo , Celulose 1,4-beta-Celobiosidase/metabolismo , Proteínas Fúngicas/metabolismo , Glucose/metabolismo , Madeira/metabolismo , Madeira/microbiologia
7.
BMC Plant Biol ; 19(1): 360, 2019 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-31419944

RESUMO

BACKGROUND: Tilletia horrida is a basidiomycete fungus that causes rice kernel smut, one of the most important rice diseases in hybrid rice growing areas worldwide. However, little is known about its mechanisms of pathogenicity. We previously reported the genome of T. horrida, and 597 genes that encoded secreted proteins were annotated. Among these were some important effector genes related to pathogenicity. RESULTS: A secretome analysis suggested that five Tilletia fungi shared more gene families than were found in other smuts, and there was high conservation between them. Furthermore, we screened 597 secreted proteins from the T. horrida genome, some of which induced expression in host-pathogen interaction processes. Through transient expression, we demonstrated that two putative effectors could induce necrosis phenotypes in Nicotiana benthamiana. These two encoded genes were up-regulated during early infection, and the encoded proteins were confirmed to be secreted using a yeast secretion system. For the putative effector gene smut_5844, a signal peptide was required to induce non-host cell death, whereas ribonuclease catalytic active sites were required for smut_2965. Moreover, both putative effectors could induce an immune response in N. benthamiana leaves. Interestingly, one of the identified potential host interactors of smut_5844 was laccase-10 protein (OsLAC10), which has been predicted to be involved in plant lignification and iron metabolism. CONCLUSIONS: Overall, this study identified two secreted proteins in T. horrida that induce cell death or are involved in defense machinery in non-host plants. This research provides a useful foundation for understanding the interaction between rice and T. horrida.


Assuntos
Basidiomycota/crescimento & desenvolvimento , Morte Celular , Proteínas Fúngicas/genética , Interações Hospedeiro-Patógeno/genética , Tabaco/microbiologia , Basidiomycota/metabolismo , Proteínas Fúngicas/metabolismo , Oryza/microbiologia , Doenças das Plantas/microbiologia , Tabaco/fisiologia
8.
Oxid Med Cell Longev ; 2019: 7417263, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31396306

RESUMO

Torularhodin, extracted from Sporidiobolus pararoseus, is a significant carotenoid that is similar to lycopene in structure. Some studies have indicated torularhodin as having antioxidative activities. However, it has not been thoroughly studied with respect to its antioxidative activity and molecular mechanisms in liver injury. Therefore, the aim of this study was to elucidate the antioxidative activity of torularhodin against hydrogen peroxide- (H2O2-) induced damage and the mechanism involved through transcriptome analysis and to explore its antioxidant potential. BRL cells were first subjected to H2O2 damage and then treated with torularhodin. The results showed that at 10-5 g/ml, torularhodin had significant protective effects against H2O2-induced oxidative damage. Morphological and immunofluorescence staining showed that torularhodin could maintain cell integrity and enhance the activity of antioxidant enzymes in the cells. According to transcriptome analysis, 2808 genes were significantly differentially expressed (1334 upregulated and 1474 downregulated) after torularhodin treatment. These genes were involved in three major Gene Ontology categories (biological process, cellular component, and molecular function). Moreover, torularhodin was involved in some cellular pathways, such as cancer inhibition, antioxidation, and aging delay. Our data highlighted the importance of multiple pathways in the antioxidative damage of liver treated with torularhodin and will contribute to get the molecular mechanisms of torularhodin inhibition of hepatic oxidative damage.


Assuntos
Carotenoides/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Animais , Antioxidantes/metabolismo , Basidiomycota/química , Basidiomycota/metabolismo , Carotenoides/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Perfilação da Expressão Gênica , Hepatócitos/citologia , Hepatócitos/metabolismo , Peróxido de Hidrogênio/farmacologia , Ratos
9.
Artigo em Inglês | MEDLINE | ID: mdl-31337007

RESUMO

Volatile fungal metabolites are responsible for various odors and may contribute to a "sick building syndrome" (SBS) with a negative effect on the heath of building. The authors have attempted to fill the research gaps by analyzing microbial volatile organic compounds (MVOCs) originating from representatives of the Basidiomycetes class that grow on wood-polymer composite (WPC) boards. WPCs have been analyzed as a material exposed to biodeterioration. Indoor air quality (IAQ) is affected by the increased use of WPCs inside buildings, and is becoming a highly relevant research issue. The emission profiles of MVOCs at various stages of WPC decay have been demonstrated in detail for Coniophora puteana and Poria placenta, and used to set the European industrial standards for wood-decay fungi. Differences in the production of MVOCs among these species of fungi have been detected using the thermal desorption-gas chromatography/mass spectrometry (TD-GC/MS) method. This study identifies the production of alcohols, aldehydes, ketones, carboxylic acids and other compounds during one month of fungal growth. The identified level of metabolites indicates a relation between the level of air pollution and condition of the WPC material, which may become part of IAQ quantification in the future. The study points to the species-specific compounds for representatives of brown and white-rot fungi and the compounds responsible for their odor. In this study, 1-Octen-3-ol was indicated as a marker for their active growth, which is also associated with SBS. The proposed experimental set-up and data analysis are a simple and convenient way to obtain emission profiles of MVOCs from microbes growing on different materials.


Assuntos
Basidiomycota/metabolismo , Cromatografia Gasosa-Espectrometria de Massas/métodos , Compostos Orgânicos Voláteis/química , Madeira/química , Poluição do Ar em Ambientes Fechados/análise , Basidiomycota/classificação , Basidiomycota/crescimento & desenvolvimento , Síndrome do Edifício Doente , Especificidade da Espécie
10.
Food Chem ; 295: 206-213, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174751

RESUMO

Auricularia auricular could be useful as a candidate for human selenium supplementation. This study examined the effects of exogenous Se on the growth, yield, nutritive value, and mineral accumulation of A. auricular. Selenate or selenite (0.5-40.0 µg g-1) had no effect on mycelium morphology or the yield of fruiting bodies. In some cases, they affected the accumulation of inter-elements and significantly decreased the concentrations of copper, iron, and chromium in the Se-enriched fruiting bodies compared to that with control treatments. The polysaccharide (116.5-131.6 µg g-1) and protein (105.2-113.4 µg g-1) content in Se-enriched fruiting bodies were not significantly different from those observed in the controls (polysaccharide, 114.1 µg g-1; protein, 105.6 µg g-1). Thus, A. auricular can absorb inorganic Se from the substrate and convert it to organic Se compounds (selenocystine (≥4.1%), selenomethionine (≥91.9%), and Se-methylselenocysteine (≥2.3%)).


Assuntos
Basidiomycota/efeitos dos fármacos , Basidiomycota/metabolismo , Selênio/farmacocinética , Basidiomycota/crescimento & desenvolvimento , Biofortificação , Cromo/análise , Cromo/metabolismo , Cobre/análise , Cobre/metabolismo , Cistina/análogos & derivados , Cistina/metabolismo , Carpóforos/química , Carpóforos/efeitos dos fármacos , Carpóforos/metabolismo , Proteínas Fúngicas/análise , Proteínas Fúngicas/metabolismo , Humanos , Ferro/análise , Ferro/metabolismo , Valor Nutritivo , Compostos Organosselênicos/metabolismo , Ácido Selênico/farmacologia , Ácido Selenioso/farmacologia , Selenocisteína/análogos & derivados , Selenocisteína/metabolismo , Selenometionina/metabolismo
11.
J Appl Microbiol ; 127(3): 724-738, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31173436

RESUMO

AIMS: We aimed to expand the microbial biocatalyst platform to generate essential oxyfunctionalized standards for pharmaceutical, toxicological and environmental research. In particular, we examined the production of oxyfunctionalized nonsteroidal anti-inflammatory drugs (NSAIDs) by filamentous-fungi. METHODS AND RESULTS: Four NSAIDs; diclofenac, ibuprofen, naproxen and mefenamic acid were used as substrates for oxyfunctionalization in a biocatalytic process involving three filamentous-fungi strains; Beauveria bassiana, Clitocybe nebularis and Mucor hiemalis. Oxyfunctionalized metabolites that are major degradation intermediates formed by Cytochrome P450 monooxygenases in human metabolism were produced in isolated yields of up to 99% using 1 g l-1 of substrate. In addition, a novel compound, 3',4'-dihydroxydiclofenac, was produced by B. bassiana. Proteomic analysis identified CYP548A5 that might be responsible for diclofenac oxyfunctionalization in B. bassiana. CONCLUSIONS: Efficient fungi catalysed oxyfunctionalization was achieved when using NSAIDs as substrates. High purities and isolated yields of the produced metabolites were achieved. SIGNIFICANCE AND IMPACT OF THE STUDY: The lack of current efficient synthetic strategies for oxyfunctionalization of NSAIDs is a bottleneck to perform pharmacokinetic, pharmacodynamic and toxicological analysis for the pharmaceutical industry. Additionally, oxyfunctionalized derivatives are needed for tracking the fate and impact of such metabolites in the environment. Herein, we described a fungi catalysed process that surpasses previously reported strategies in terms of efficiency, to synthesize oxyfunctionalized NSAIDs.


Assuntos
Anti-Inflamatórios não Esteroides/metabolismo , Fungos/metabolismo , Basidiomycota/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Diclofenaco/metabolismo , Ibuprofeno/metabolismo , Ácido Mefenâmico/metabolismo , Mucor/metabolismo , Naproxeno/metabolismo , Proteômica
12.
Carbohydr Polym ; 220: 191-201, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31196540

RESUMO

Development of sustainable biomaterials from wasted resources has been widely advocated recently. In this study, chitin was extracted from Hericium erinaceus residues and used as the main framework to in situ synthesize series of magnetic chitin hydrogels for Cu2+ removal. Results showed that the extracted chitin with 1.56 × 105 g/mol molecular weight and 51.83% degree of acetylation was completely composed of glucosamine. After introduction of Fe3O4 particles, the magnetic chitin hydrogels exhibited preferable adsorption capacity for Cu2+ than its native form. Besides, the magnetic chitin hydrogels showed paramagnetic behavior and improved mechanical property but the slight reduced swelling and thermal performance. Moreover, the swelling, mechanical, magnetic and adsorption properties were found to be Fe3O4 content-dependent, indicating its specific tunable performance. Therefore, this work provided a new alternative renewable resource for chitin and facile procedure to prepare magnetic chitin hydrogels as a promising candidate material for heavy metal removal system.


Assuntos
Basidiomycota/metabolismo , Quitina/química , Hidrogéis/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Adsorção , Cobre/química , Cinética , Imãs
13.
Z Naturforsch C J Biosci ; 74(7-8): 201-210, 2019 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-31199781

RESUMO

Two edible, cultivable mushroom species of the family Strophariaceae, Kuehneromyces mutabilis (sheathed woodtuft) and Hypholoma capnoides (conifer tuft), were studied using proton nuclear magnetic resonance metabolomic approach. The variation in the metabolites of the two species and their metabolic behaviour regarding caps and stipes and different collection sites were analysed by multivariate analysis methods. Altogether 169 cap and stipe samples of the mushrooms were investigated. The clearest difference between the species was in the sugar composition, which was more diverse in H. capnoides. When mushroom samples collected from different locations were compared, more variance was found in H. capnoides, whereas K. mutabilis appeared more homogeneous as a species. As far as the caps and stipes were concerned, in both species the amount of α-α-trehalose was clearly higher in the stipes, and the caps contained a larger proportion of the amino acids and organic acids.


Assuntos
Basidiomycota/metabolismo , Metaboloma , Basidiomycota/química , Basidiomycota/classificação , Espectroscopia de Ressonância Magnética
14.
J Basic Microbiol ; 59(8): 846-852, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31215677

RESUMO

In the present study, 20 psychrotolerant yeast species isolated from the soils of King George Island in the sub-Antarctic region were evaluated for the production of extracellular gelatinase, an enzyme with high potential for applications in diverse areas, such as food and medicine. The production of extracellular gelatinase was confirmed in the yeasts Metschnikowia sp., Leucosporidium fragarium, and Mrakia sp., the last one being the yeast in which the highest gelatinase activity was detected. The enzyme was purified from cultures of Mrakia sp., and the effect of different physical-chemical factors on its activity was determined. The gelatinase produced by Mrakia sp. would correspond to a protein of relative molecular weight (rMW) 37,000, which displayed the highest activity at 36°C, pH 7.0, 10 mM CaCl 2 , and 5 mM ZnSO 4 .


Assuntos
Basidiomycota/enzimologia , Proteínas Fúngicas/metabolismo , Gelatinases/metabolismo , Regiões Antárticas , Basidiomycota/metabolismo , Cloreto de Cálcio , Proteínas Fúngicas/química , Proteínas Fúngicas/isolamento & purificação , Gelatinases/química , Gelatinases/isolamento & purificação , Concentração de Íons de Hidrogênio , Metschnikowia/enzimologia , Metschnikowia/metabolismo , Peso Molecular , Temperatura Ambiente , Sulfato de Zinco
15.
Int. microbiol ; 22(2): 203-215, jun. 2019. graf, tab
Artigo em Inglês | IBECS | ID: ibc-184827

RESUMO

The enzymatic and non-enzymatic antioxidant activities of a solid-state fermentation system (SSFS) employing six basidiomycete and four ascomycete fungi on orange peel have been evaluated. Class comparisons revealed highly significant effect of fungal group on the antioxidant activity. Peroxidase activity appeared only in the basidiomycete fungi (particularly Pleurotus columbinus, Ganoderma resinaceum, and Pleurotus floridanus) whereas catalase activity appeared in the two fungal groups in favor of the ascomycetes (particularly Paecilomyces variotii and Aspergillus fumigatus). Maximal peroxidase and minimal catalase activities were found at moderate phenolic content, with extreme phenolic levels leading to low peroxidase activity but high catalase activity. Production of the non-enzymatic antioxidants (phenolics, flavonoids, reducing power, and DPPH scavenging) was in favor of the ascomycetes, which showed great native ability to synthesize flavonoids and also to release flavonoids from orange peel. The basidiomycete fungi, which have limited native ability to produce phenolics, had high ability to consume orange peel phenolics. By contrast, the ascomycete fungi exhibited great native ability for production of phenolics and low ability to consume exogenous phenolics


No disponible


Assuntos
Antioxidantes/análise , Ascomicetos/crescimento & desenvolvimento , Basidiomycota/crescimento & desenvolvimento , Reatores Biológicos/microbiologia , Peroxidase/análise , Meios de Cultura/química , Ascomicetos/metabolismo , Basidiomycota/metabolismo , Catalase/análise , Fermentação
16.
Int. microbiol ; 22(2): 255-264, jun. 2019. graf, tab
Artigo em Inglês | IBECS | ID: ibc-184832

RESUMO

Fungi are used for the production of several compounds and the efficiency of biotechnological processes is directly related to the metabolic activity of these microorganisms. The reactions catalyzed by lignocellulolytic enzymes are oxidative and generate reactive oxygen species (ROS). Excess of ROS can cause serious damages to cells, including cell death. Thus, the objective of this work was to evaluate the lignocellulolytic enzymes produced by Pleurotus sajor-caju CCB020, Phanerochaete chrysosporium ATCC 28326, Trichoderma reesei RUT-C30, and Aspergillus niger IZ-9 grown in sugarcane bagasse and two yeast extract (YE) concentrations and characterize the antioxidant defense system of fungal cells by the activities of superoxide dismutase (SOD) and catalase (CAT). Pleurotus sajor-caju exhibited the highest activities of laccase and peroxidase in sugarcane bagasse with 2.6 g of YE and an increased activity of manganese peroxidase in sugarcane bagasse with 1.3 g of YE was observed. However, P. chrysosporium showed the highest activities of exoglucanase and endoglucanase in sugarcane bagasse with 1.3 g of YE. Lipid peroxidation and variations in SOD and CAT activities were observed during the production of lignocellulolytic enzymes and depending on the YE concentrations. The antioxidant defense system was induced in response to the oxidative stress caused by imbalances between the production and the detoxification of ROS


No disponible


Assuntos
Antioxidantes/análise , Ascomicetos/enzimologia , Ascomicetos/metabolismo , Basidiomycota/enzimologia , Hidrolases/metabolismo , Lignina/metabolismo , Catalase/análise , Basidiomycota/metabolismo , Celulose/metabolismo , Fermentação , Oxirredução , Espécies Reativas de Oxigênio/metabolismo , Espécies Reativas de Oxigênio/toxicidade , Saccharum/metabolismo , Superóxido Dismutase/análise
17.
Prep Biochem Biotechnol ; 49(8): 767-774, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31050593

RESUMO

The cell wall of carotenoids producing yeast Sporidiobolus pararoseus was broken through five different methods: acid-heating method, dimethyl sulfoxide (DMSO) method, enzymatic method, high-pressure homogenization (HPH) method, and cell autolysis method. HPH method not only brought the optimum breaking effect (wall-breaking extent of 72.3%) and the highest carotenoid extraction rate (67.2%), but also had the advantages of short-time, simple process, safe, and pollution-free. After optimization, the wall-breaking extent and the carotenoid extraction rate were enhanced to 78.3% and 82.5%, respectively. And the optimum conditions of HPH were obtained as homogenization pressure 80 MPa, bacterial liquid concentration 8% and homogenization for three times. Moreover, cell experiments demonstrated that all of the four carotenoids (ß-carotene, γ-carotene, torulene, and torularhodin) purified from intracellular products of S. pararoseus. had the effect of resistance to oxidative damage from hydrogen peroxide on SK-HEP-1 cells, and torulene showed the most notable effect among them.


Assuntos
Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Basidiomycota/metabolismo , Carotenoides/isolamento & purificação , Carotenoides/farmacologia , Parede Celular/metabolismo , Antioxidantes/química , Antioxidantes/metabolismo , Carotenoides/química , Carotenoides/metabolismo , Linhagem Celular , Dimetil Sulfóxido/metabolismo , Calefação , Humanos , Microbiologia Industrial/métodos , Estresse Oxidativo/efeitos dos fármacos , Pressão , Leveduras/metabolismo
18.
Chem Biol Interact ; 308: 61-69, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31100278

RESUMO

The objective of this work was to investigate the effect of boletus polysaccharide (BPS) on diabetic hepatopathy in streptozotocin (STZ)-induced type 2 diabetes mellitus (T2DM) rats for the first time. The rats were fed with high-fat diet (HFD) for 4 weeks and induced with STZ by a single intraperitoneal injection to develop T2DM model. The HFD was given continually for another 4 weeks after diabetes induction, following the drugs of BPS (400 mg/kg bw/day) infused to stomach of rats once a day. After the administration, blood was drawn from the posterior orbital venous plexus of the inner canthus and the rats were then sacrificed. The blood glucose and lipid, alanine transaminase (ALT) and aspartate transaminase (AST) were detected immediately. Besides, their livers were dissected for biochemical and histopathological assays. And the levels of malonaldehyde, glutathione and antioxidant enzymes in liver were detected. In addition, histopathological examinations of liver were performed to verify the liver injury. The expressions of NF-κB, TNF-α, SREBP1c, and CYP7A1 were test to trace out the mechanistic pathways. Compared with T2DM model group, the blood glucose, TC, TG, ALT, AST, and MDA and so on were significantly reduced, and CAT, SOD, GSH, GPx were significantly increased in the rats treated with BPS. The histopathological examination showed the liver injury in BPS treated rats was alleviated. The expressions of SREBP1c, NF-κB and TNF-α were significantly decreased, and the expressions of CYP7A1 was significantly increased. All these experimental findings demonstrate that BPS exhibited antidiabetic effects rats possibly through its inhibition of oxidative stress and inflammation, supporting that BPS has a promising therapeutic effect in the treatment of diabetic hepatopathy in rats.


Assuntos
Hipoglicemiantes/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Polissacarídeos/farmacologia , Alanina Transaminase/sangue , Animais , Antioxidantes/metabolismo , Aspartato Aminotransferases/sangue , Basidiomycota/metabolismo , Glicemia/análise , Colesterol 7-alfa-Hidroxilase/metabolismo , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/patologia , Dieta Hiperlipídica , Hipoglicemiantes/uso terapêutico , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , NF-kappa B/metabolismo , Polissacarídeos/uso terapêutico , Ratos , Ratos Wistar , Proteína de Ligação a Elemento Regulador de Esterol 2/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
19.
Fungal Biol ; 123(6): 456-464, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31126422

RESUMO

We compared the δ13C and δ15N of forest material with an extensive sporocarp collection to elucidate the role of litter, wood and soil as fungal carbon and nitrogen sources in Finnish boreal Picea abies-dominated forests. Ectomycorrhizal Hydnum and Cortinarius had higher δ15N than other ectomycorrhizal fungi, suggesting use of 15N-enriched, deeper nitrogen. Russula had lower δ15N than other ectomycorrhizal fungi and resembled some litter decay genera, suggesting use of litter-derived nitrogen. There was little variation in δ15N among other genera of ectomycorrhizal fungi, indicating limited functional diversity in nitrogen use. Saprotrophic Leotia, Gymnopus, Hypholoma, Pholiota, Rhodocollybia and Calocera had δ15N values similar to ectomycorrhizal fungi, indicating overlap in use of older nitrogen from soil or roots or use of newly fixed nitrogen. Genera of litter and wood decay fungi varied up to 6‰ in δ13C and 10‰ in δ15N, suggesting large differences in carbon and nitrogen sources and processing. Similar δ13C between white and brown rot wood decay fungi also suggest that white rot fungi do not use lignin-derived carbon. Together, these δ13C and δ15N patterns of fungi from Finnish boreal forests enhance our knowledge of fungal functional diversity and indicate broad use of litter, wood and soil resources.


Assuntos
Carbono/metabolismo , Fungos/metabolismo , Micorrizas/metabolismo , Nitrogênio/metabolismo , Abies , Basidiomycota/metabolismo , Finlândia , Taiga , Madeira/microbiologia
20.
Braz J Microbiol ; 50(3): 625-632, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31030410

RESUMO

The effects of different three carbon sources, that is, glucose, fructose, and sucrose, on production, molecular properties and antiproliferative activity of exopolysaccharide (EPS), were evaluated in the submerged culture of Scleroderma areolatum Ehrenb. Among carbon sources examined, the addition of sucrose maximizes the mycelia production, while fructose could maximize the EPS yield. Although the predominant carbohydrate compositions identified were gluconic acid and mannose, the monosaccharide composition of EPSs was also different significantly. FT-IR spectral analysis revealed there was no significant difference among the prominent characteristic groups in three EPSs. The molecular weight of EPSs was also affected by carbon source, being generally lower compared with that with glucose. However, all EPSs molecule existed as nearly globular shape form in aqueous solution. The variation of carbon sources also affected antiproliferative activity examined in vitro using cell proliferation assay. Fructose was optimal carbon source giving higher antiproliferative activity probably due to the relatively high contents of xylose in the EPS with low molecular weight.


Assuntos
Basidiomycota/metabolismo , Carbono/metabolismo , Inibidores do Crescimento/química , Inibidores do Crescimento/farmacologia , Polissacarídeos/química , Polissacarídeos/farmacologia , Basidiomycota/química , Basidiomycota/crescimento & desenvolvimento , Carbono/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Meios de Cultura/química , Meios de Cultura/metabolismo , Inibidores do Crescimento/metabolismo , Humanos , Peso Molecular , Polissacarídeos/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier
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