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1.
Food Chem ; 346: 128896, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33421901

RESUMO

Type of the wood used for the aging highly influences the quality of alcoholic beverages. In this research we explored the potential of cyclic voltammetry (CV) and differential pulse voltammetry (DPV) to establish fingerprints characteristic for each wood and to enable determining the type of the wood used in the aging process. Eleven different wood samples were used to prepare three different types of spirits during 15 months. The highest extraction rate was obtained during the first month, while further aging was followed with almost constant amount of extracted polyphenols. Black locust, myrobalan plum, and mulberry extracts were discriminated from the spirits aged in oak and wild cherry wood when statistical analysis was applied. Although clear classification of all samples was not achieved, this long term study demonstrated a potential of both CV and DPV for differentiating wood species used in the aging, hence in the quality control of spirits.


Assuntos
Bebidas Alcoólicas/análise , Fracionamento Químico/métodos , Solventes/química , Madeira/química , Frutas/química , Química Verde , Fatores de Tempo , Madeira/microbiologia
2.
Ecotoxicol Environ Saf ; 203: 110997, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32684518

RESUMO

A novel study on biodegradation of 30 mg L-1 of Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) mixture (celecoxib, diclofenac and ibuprofen) by two wood-rot fungi; Ganoderma applanatum (GA) and Laetiporus sulphureus (LS) was investigated for 72 h. The removal efficiency of celecoxib, diclofenac and ibuprofen were 98, 96 and 95% by the fungal consortium (GA + LS). Although, both GA and LS exhibited low removal efficiency (61 and 73% respectively) on NSAIDs. However, 99.5% degradation of the drug mixture (NSAIDs) was achieved on the addition of the fungal consortium (GA + LS) to the experimental set-up. Overall, LS exhibited higher degradation efficiency; 92, 87, 79% on celecoxib, diclofenac and ibuprofen than GA with 89, 80 and 66% respectively. Enzyme analyses revealed significant induction of 201, 180 and 135% in laccase (Lac), lignin peroxidase (LiP) and manganese peroxidase (MnP) by the fungal consortium during degradation of the NSAIDs respectively. The experimental data showed the best goodness of fit when subjected to Langmuir (R2 = 0.980) and Temkin (R2 = 0.979) isotherm models which suggests monolayer and heterogeneous nature exhibited by the mycelia during interactions with NSAIDs. The degradation mechanism followed pseudo-second-order kinetic model (R2 = 0.987) indicating the strong influence of fungal biomass in the degradation of NSAIDs. Furthermore, Gas Chromatography-Mass Spectrometry (GCMS) and High-Performance Liquid Chromatography (HPLC) analyses confirmed the degraded metabolic states of the NSAIDs after treatment with GA, LS and consortium (GA + LS). Hence, the complete removal of NSAIDs is best achieved in an economical and eco-friendly way with the use of fungi consortium.


Assuntos
Anti-Inflamatórios não Esteroides/análise , Poluentes Ambientais/análise , Ganoderma/enzimologia , Ganoderma/crescimento & desenvolvimento , Lignina/metabolismo , Madeira/microbiologia , Anti-Inflamatórios não Esteroides/metabolismo , Biodegradação Ambiental , Biomassa , Poluentes Ambientais/metabolismo , Indução Enzimática/efeitos dos fármacos , Cinética , Lacase/biossíntese , Modelos Biológicos , Peroxidases/biossíntese
3.
Int J Food Microbiol ; 333: 108780, 2020 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-32682208

RESUMO

Several materials such as plastic, wood, cardboard or stainless steel are used as working surfaces or packaging in direct contact with foodstuffs. In food industries, the hygienic surface status is one of the criteria to product conform packaging as described in the European regulation ECR 1935/2004. Today in European Union, it exists one harmonized regulation specific for Food Contact material made of plastic called EU N°10/2011 (Anonymous 2011a). This regulation specifies that materials intended for safe foodstuff contact must not modify food characteristics in terms of chemical, microbiological and sensorial properties. This study aims to compare the survival and transfer of Penicillium expansum conidia and Escherichia coli cells from several materials to apples. Poplar, cardboards, newly manufactured plastic and reusable plastic specimens were artificially inoculated with both microorganisms, subsequently put in contact with apples and stored under realistic storage conditions. After incubation for up to 1 week, apples and specimens were analysed to assess the survival of the microorganisms and their transfer from materials to apples. While P. expansum survived and did not grow on any of the materials, E. coli mortality was observed after 1 h on wood and cardboard and after 1 week on both plastics. The proportion of microorganisms transferred was different according to the considered material. This transfer was lower than 1% for wood.


Assuntos
Escherichia coli/isolamento & purificação , Malus/microbiologia , Penicillium/isolamento & purificação , Plásticos/análise , Aço Inoxidável/análise , Madeira/microbiologia , Contaminação de Alimentos/análise , Microbiologia de Alimentos
4.
Int J Syst Evol Microbiol ; 70(7): 4217-4223, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32589574

RESUMO

Five yeast strains were isolated from the gut of the groundbeetle Pterostichus gebleri and rotting wood, which were collected from two different localities in China. These strains were identified as representing two novel species of the genus Blastobotrys through comparison of sequences in the D1/D2 domains of the LSU rRNA gene and other taxonomic characteristics. Blastobotrys baotianmanensis sp. nov. produces two to three spherical ascospores per ascus, and is most closely related to the type strains of B. elegans, B. capitulata, B. arbuscula, and an undescribed species represented by strain BG02-7-20-006A-3-1. Blastobotrys baotianmanensis sp. nov. differed from these strains by 3.6-8.4 % divergence (21-46 substitutions and 0-4 gaps) in the D1/D2 sequences. Blastobotrys xishuangbannaensis f.a., sp. nov. is closely related to B. nivea, B. elegans and B. aristata but the formation of ascospores was not observed on various sporulation media, and it differed from its relatives by 6.2-8.5 % divergence (34-43 substitutions and 2-6 gaps) in the D1/D2 sequences. The holotype of Blastobotrys baotianmanensis sp. nov. is NYNU 1581 and the holotype of Blastobotrys xishuangbannaensis f.a., sp. nov. is NYNU 181030.


Assuntos
Besouros/microbiologia , Filogenia , Saccharomycetales/classificação , Madeira/microbiologia , Animais , China , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Técnicas de Tipagem Micológica , Saccharomycetales/isolamento & purificação , Análise de Sequência de DNA , Esporos Fúngicos
5.
Int J Syst Evol Microbiol ; 70(7): 4378-4383, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32584748

RESUMO

Four isolates of two novel ascosporogenous species belonging to the clade Starmera were obtained from cactus tissues and rotting wood in Brazil. Results of analyses of the sequences of the ITS and D1/D2 domains of the large subunit rRNA gene indicated that the two isolates of the cactophilic species are related to Starmera caribaea and Starmera pilosocereana, yeasts that are associated with cacti and require an organic source of sulfur for growth. We propose the novel species Starmera foglemanii sp. nov. (CBS 16113T; MycoBank number: MB 834400) to accommodate these isolates. The other two isolates are phylogenetically related to Candida dendrica, Candida laemsonensis and Candida berthetii, also in the Starmera clade. The novel species name Starmera ilhagrandensis sp. nov. (CBS 16316T; MycoBank number: MB 834402) is proposed for this species.


Assuntos
Cactaceae/microbiologia , Filogenia , Saccharomycetales/classificação , Madeira/microbiologia , Brasil , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Técnicas de Tipagem Micológica , Saccharomycetales/isolamento & purificação , Análise de Sequência de DNA
6.
Proc Natl Acad Sci U S A ; 117(21): 11551-11558, 2020 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-32404424

RESUMO

As the primary decomposers of organic material in terrestrial ecosystems, fungi are critical agents of the global carbon cycle. Yet our ability to link fungal community composition to ecosystem functioning is constrained by a limited understanding of the factors accounting for different wood decomposition rates among fungi. Here we examine which traits best explain fungal decomposition ability by combining detailed trait-based assays on 34 saprotrophic fungi from across North America in the laboratory with a 5-y field study comprising 1,582 fungi isolated from 74 decomposing logs. Fungal growth rate (hyphal extension rate) was the strongest single predictor of fungal-mediated wood decomposition rate under laboratory conditions, and accounted for up to 27% of the in situ variation in decomposition in the field. At the individual level, decomposition rate was negatively correlated with moisture niche width (an indicator of drought stress tolerance) and with the production of nutrient-mineralizing extracellular enzymes. Together, these results suggest that decomposition rates strongly align with a dominance-tolerance life-history trade-off that was previously identified in these isolates, forming a spectrum from slow-growing, stress-tolerant fungi that are poor decomposers to fast-growing, highly competitive fungi with fast decomposition rates. Our study illustrates how an understanding of fungal trait variation could improve our predictive ability of the early and midstages of wood decay, to which our findings are most applicable. By mapping our results onto the biogeographic distribution of the dominance-tolerance trade-off across North America, we approximate broad-scale patterns in intrinsic fungal-mediated wood decomposition rates.


Assuntos
Fungos/fisiologia , Madeira/microbiologia , Ciclo do Carbono/fisiologia , Ecossistema , Fungos/classificação , Fungos/enzimologia , Hifas/fisiologia , Micobioma/fisiologia , América do Norte
7.
Int J Syst Evol Microbiol ; 70(6): 3731-3739, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32453684

RESUMO

A bacterial strain CC-CTC003T was isolated from a synthetic wooden board. Cells of strain CC-CTC003T were Gram-stain-negative, rod-shaped, motile by gliding and formed yellow colonies. Optimal growth occurred at 25 °C, pH 7 and in the presence of 1 % NaCl. The phylogenetic analyses based on 16S rRNA genes revealed that strain CC-CTC003T belonged to the genus Flavobacterium and was most closely related to Flavobacterium cerinum (95.3 % sequence identity), Flavobacterium maris (94.9 % sequence identity), Flavobacterium qiangtangense (94.8 %) and Flavobacterium subsaxonicum (94.7 %) and had less than 94.7 % sequence similarity to other members of the genus. Average nucleotide identity (ANI) values between strain CC-CTC003T and the type strains of other closely related species were 70.1-74.1 %. The digital DNA-DNA hybridization (dDDH) with F. cerinum was 19.4 %. Strain CC-CTC003T contained C15 : 0, iso-C15 : 0, iso-C15 : 0 3-OH, iso-C17 : 0 3-OH, summed feature 3 (C16 : 1 ω6c / C16 : 1 ω7c) and summed feature 9 (C16 : 0 10-methyl / iso-C17 : 1 ω9c) as the predominant fatty acids. The polar lipid profile consisted of phosphatidylethanolamine, four uncharacterized aminophospholipids, two aminolipids and one unidentified glycolipid. The major polyamine was sym-homospermidine and contained MK-6 as major isoprenoid quinone. The DNA G+C content of the genomic DNA was 39.2 mol%. On the basis of the phylogenetic inference and phenotypic data, strain CC-CTC003T should be classified as a novel species, for which the name Flavobacterium supellecticarium sp. nov. is proposed. The type strain is CC-CTC003T (=BCRC 81146T=JCM 32838T).


Assuntos
Materiais de Construção/microbiologia , Flavobacterium/classificação , Filogenia , Madeira/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Flavobacterium/isolamento & purificação , Hibridização de Ácido Nucleico , Fosfolipídeos/química , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Espermidina/análogos & derivados , Espermidina/química , Taiwan , Vitamina K 2/análogos & derivados , Vitamina K 2/química
8.
Arch Microbiol ; 202(7): 1729-1739, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32328754

RESUMO

We isolated two Candida pseudointermedia strains from the Atlantic rain forest in Brazil, and analyzed cellobiose metabolization in their cells. After growth in cellobiose medium, both strains had high intracellular ß-glucosidase activity [~ 200 U (g cells)-1 for 200 mM cellobiose and ~ 100 U (g cells)-1 for 2 mM pNPßG] and negligible periplasmic cellobiase activity. During batch fermentation, the strain with the best performance consumed all the available cellobiose in the first 18 h of the assay, producing 2.7 g L-1 of ethanol. Kinetics of its cellobiase activity demonstrated a high-affinity hydrolytic system inside cells, with Km of 12.4 mM. Our data suggest that, unlike other fungal species that hydrolyze cellobiose extracellularly, both analyzed strains transport it to the cytoplasm, where it is then hydrolyzed by high-affinity intracellular ß-glucosidases. We believe this study increases the fund of knowledge regarding yeasts from Brazilian microbiomes.


Assuntos
Candida/enzimologia , Celobiose/metabolismo , Madeira/metabolismo , Madeira/microbiologia , beta-Glucosidase/metabolismo , Brasil , Candida/isolamento & purificação , Candida/metabolismo , Metabolismo dos Carboidratos , Etanol/metabolismo , Fermentação , Hidrólise , Cinética
9.
J Appl Microbiol ; 129(3): 590-600, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32259336

RESUMO

AIMS: This study was done to obtain denitrifiers that could be used for bioaugmentation in woodchip bioreactors to remove nitrate from agricultural subsurface drainage water. METHODS AND RESULTS: We isolated denitrifiers from four different bioreactors in Minnesota, and characterized the strains by measuring their denitrification rates and analysing their whole genomes. A total of 206 bacteria were isolated from woodchips and thick biofilms (bioslimes) that formed in the bioreactors, 76 of which were able to reduce nitrate at 15°C. Among those, nine potential denitrifying strains were identified, all of which were isolated from the woodchip samples. Although many nitrate-reducing strains were isolated from the bioslime samples, none were categorized as denitrifiers but instead as carrying out dissimilatory nitrate reduction to ammonium. CONCLUSIONS: Among the denitrifiers confirmed by 15 N stable isotope analysis and genome analysis, Cellulomonas cellasea strain WB94 and Microvirgula aerodenitrificans strain BE2.4 appear to be promising for bioreactor bioaugmentation due to their potential for both aerobic and anaerobic denitrification, and the ability of strain WB94 to degrade cellulose. SIGNIFICANCE AND IMPACT OF THE STUDY: Denitrifiers isolated in this study could be useful for bioaugmentation application to enhance nitrate removal in woodchip bioreactors.


Assuntos
Agricultura/métodos , Reatores Biológicos/microbiologia , Desnitrificação , Purificação da Água/métodos , Madeira/microbiologia , Betaproteobacteria/isolamento & purificação , Betaproteobacteria/metabolismo , Biodegradação Ambiental , Cellulomonas/isolamento & purificação , Cellulomonas/metabolismo , Minnesota , Nitratos/isolamento & purificação , Nitratos/metabolismo , Madeira/metabolismo
10.
PLoS One ; 15(4): e0232145, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32324822

RESUMO

Microorganisms are constantly interacting in a given environment by a constant exchange of signaling molecules. In timber, wood-decay fungi will come into contact with other fungi and bacteria. In naturally bleached wood, dark, pigmented lines arising from confrontation of two fungi often hint at such interactions. The metabolites (and pigment) exchange was investigated using the lignicolous basidiomycete Schizophyllum commune, and co-occurring fungi and bacteria inoculated directly on sterilized wood, or on media. In interactions with competitive wood degrading fungi, yeasts or bacteria, different competition strategies and communication types were observed, and stress reactions, as well as competitor-induced enzymes or pigments were analyzed. Melanin, indole, flavonoids and carotenoids were shown to be induced in S. commune interactions. The induced genes included multi-copper oxidases lcc1, lcc2, mco1, mco2, mco3 and mco4, possibly involved in both pigment production and lignin degradation typical for wood bleaching by wood-decay fungi.


Assuntos
Schizophyllum/metabolismo , Bactérias/metabolismo , Pigmentos Biológicos/metabolismo , Metabolismo Secundário/fisiologia , Madeira/microbiologia
11.
PLoS One ; 15(2): e0221742, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32023247

RESUMO

Wood and wood products can harbor microorganisms that can raise phytosanitary concerns in countries importing or exporting these products. To evaluate the efficacy of wood treatment on the survival of microorganisms of phytosanitary concern the method of choice is to grow microbes in petri dishes for subsequent identification. However, some plant pathogens are difficult or impossible to grow in axenic cultures. A molecular methodology capable of detecting living fungi and fungus-like organisms in situ can provide a solution. RNA represents the transcription of genes and can become rapidly unstable after cell death, providing a proxy measure of viability. We designed and used RNA-based molecular diagnostic assays targeting genes essential to vital processes and assessed their presence in wood colonized by fungi and oomycetes through reverse transcription and real-time polymerase chain reaction (PCR). A stability analysis was conducted by comparing the ratio of mRNA to gDNA over time following heat treatment of mycelial cultures of the Oomycete Phytophthora ramorum and the fungus Grosmannia clavigera. The real-time PCR results indicated that the DNA remained stable over a period of 10 days post treatment in heat-treated samples, whereas mRNA could not be detected after 24 hours for P. ramorum or 96 hours for G. clavigera. Therefore, this method provides a reliable way to evaluate the viability of these pathogens and offers a potential way to assess the effectiveness of existing and emerging wood treatments. This can have important phytosanitary impacts on assessing both timber and non-timber forest products of commercial value in international wood trade.


Assuntos
Ophiostomatales/isolamento & purificação , Phytophthora/isolamento & purificação , Madeira/microbiologia , Sobrevivência Celular , DNA Fúngico/análise , Ophiostomatales/citologia , Ophiostomatales/genética , Phytophthora/citologia , Phytophthora/genética , Doenças das Plantas/microbiologia , Reação em Cadeia da Polimerase , RNA Fúngico/análise
12.
Int J Mol Sci ; 21(3)2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-32033175

RESUMO

In the United Arab Emirates (UAE), royal poinciana (Delonix regia) trees suffer from stem canker disease. Symptoms of stem canker can be characterized by branch and leaf dryness, bark lesions, discoloration of xylem tissues, longitudinal wood necrosis and extensive gumming. General dieback signs were also observed leading to complete defoliation of leaves and ultimately death of trees in advanced stages. The fungus, Neoscytalidium dimidiatum DSM 109897, was consistently recovered from diseased royal poinciana tissues; this was confirmed by the molecular, structural and morphological studies. Phylogenetic analyses of the translation elongation factor 1-a (TEF1-α) of N. dimidiatum from the UAE with reference specimens of Botryosphaeriaceae family validated the identity of the pathogen. To manage the disease, the chemical fungicides, Protifert®, Cidely® Top and Amistrar® Top, significantly inhibited mycelial growth and reduced conidial numbers of N. dimidiatum in laboratory and greenhouse experiments. The described "apple bioassay" is an innovative approach that can be useful when performing fungicide treatment studies. Under field conditions, Cidely® Top proved to be the most effective fungicide against N. dimidiatum among all tested treatments. Our data suggest that the causal agent of stem canker disease on royal poinciana in the UAE is N. dimidiatum.


Assuntos
Ascomicetos/genética , Fabaceae/microbiologia , Doenças das Plantas/microbiologia , Doenças das Plantas/terapia , Caules de Planta/microbiologia , Ascomicetos/efeitos dos fármacos , Fungicidas Industriais/farmacologia , Fator 1 de Elongação de Peptídeos/genética , Filogenia , Emirados Árabes Unidos , Madeira/microbiologia
13.
Biomed Res Int ; 2020: 9497215, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32076622

RESUMO

High-yield pulps (HYPs), such as CTMP (chemi-thermo-mechanical pulp), are attractive due to their low cost and high wood utilization. However, their drawback of rapid brightness reversion (yellowing) limits wide use of the HYPs. In this study, a fungus, Fusarium concolor X4, was applied to treat poplar CTMP for exploring the effects of biotreatment on brightness and light-induced yellowing of the pulp. The results indicated that the biotreatment with Fusarium concolor X4 could improve the brightness of poplar CTMP and inhibit light-induced yellowing of the pulp. The yellowing inhibition mechanism was explored by the analysis of enzyme production regularity during biotreatment, changes in chemical components, and the UV-Vis absorption spectra and FTIR-ATR spectra of pulps before and after biotreatment.


Assuntos
Fusarium/efeitos da radiação , Luz , Madeira/microbiologia , Celulose , Fusarium/patogenicidade , Lignina , Raios Ultravioleta , Xilosidases
14.
Sci Rep ; 10(1): 3435, 2020 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-32103052

RESUMO

The popular medicinal mushroom Ganoderma lucidum (Fr.) Karst. [Ling Zhi] has been widely used for the general promotion of health and longevity in Asian countries. Continuous cultivation may affect soil microbe and soil properties. However, the effect of G. lucidum cultivation on related wood segments, soil and tree roots microbial communities and soil properties is remain unknown. In our study, the microbial communities of soils, wood segments, and tree roots before and after G. lucidum cultivation were investigated by Illumina Miseq sequencing of both ITS and 16S rDNA, and taxonomic composition of eukaryotic and prokaryotic microorganisms were observed. Indices of microbial richness, diversity and evenness significantly differed between before and after G. lucidum cultivation. Each of the investigated sampling type harbored a distinctive microbial community and differed remarkably before and after G. lucidum cultivation. Ascomycota and Basidiomycota (fungi), Proteobacteria and Actinobacteria (bacteria) showed significant differences after Ling Zhi cultivation. The soil property values also changed after cultivation. The redundancy analysis (RDA) showed that both the fungal and bacterial community structure significantly correlated with soil humus, pH, nitrogen, carbon and trace elements (Fe, Zn, Mn, Cu) contents. The results indicated that G. lucidum cultivation may have significant differed the associated microbial community structures and soil properties. The study will provide useful information for G. lucidum cultivation and under-forest economic development.


Assuntos
Reishi/crescimento & desenvolvimento , Microbiologia do Solo , Solo/química , Madeira/microbiologia , Actinobacteria/genética , Actinobacteria/isolamento & purificação , Ascomicetos/genética , Ascomicetos/isolamento & purificação , Basidiomycota/genética , Basidiomycota/isolamento & purificação , Microbiota , Raízes de Plantas/microbiologia , Proteobactérias/genética , Proteobactérias/isolamento & purificação , RNA Ribossômico 16S/química , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Análise de Sequência de DNA
15.
Sci Rep ; 10(1): 3057, 2020 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-32080243

RESUMO

Among terrestrial microorganisms, mushroom-forming fungi have been relatively well investigated, however the inconspicuous strains may be overlooked by conventional visual investigations causing underestimation of their phylogenetic diversity. Herein, we sought to obtain a comprehensive phylogenetic diversity profile for the early-diverging wood-decaying mushrooms Dacrymycetes, using an approach that combines fruiting-body collection, culture isolation, and environmental DNA (eDNA) metabarcoding of decaying branches. Among the 28 operational taxonomic units (OTUs) detected during a three-year investigation, 10 each were from fruiting bodies and cultured mycelia and 27 were detected as eDNA sequences. eDNA metabarcoding revealed various lineages across the Dacrymycetes phylogeny. Alternatively, fruiting-body and culture surveys uncovered only ~50% of the OTUs detected through eDNA metabarcoding, suggesting that several inconspicuous or difficult-to-isolate strains are latent in the environment. Further, eDNA and culture surveys revealed early-diverging clades that were not identified in the fruiting-body survey. Thus, eDNA and culture-based techniques can uncover inconspicuous yet phylogenetically important mushroom lineages that may otherwise be overlooked via typical visual investigations.


Assuntos
Agaricales/classificação , Biodiversidade , Código de Barras de DNA Taxonômico/métodos , Filogenia , Madeira/microbiologia , Sequência de Bases , Intervalos de Confiança , Florestas , Modelos Lineares , Estações do Ano
16.
Int J Biol Macromol ; 147: 420-427, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31926920

RESUMO

Developing natural preservatives for wood protection is of great interest in sustainable construction and green building industries. This study was designed to determine the feasibility of using methyl-ß-cyclodextrin-essential oils (MßCD-EOs) complexes as potential bio-based preservatives for wood protection. Four essential oils (EOs) with proven antifungal properties, eugenol (EG), trans-cinnamaldehyde (CN), thymol (TM) and carvacrol (CV), were complexed with methyl-ß-cyclodextrin (MßCD) by a co-precipitation method. The inclusion of EOs in MßCD and the corresponding inclusion yield of the MßCD-EOs complexes were determined by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and ultraviolet-visible spectroscopy (UV/Vis), respectively. The maximum inclusion yields in MßCD-EG, MßCD-CN, MßCD-CV, and MßCD-TM were estimated to be almost 100%. MßCD-EOs complexes were impregnated into southern pine wood blocks and exposed to two brown rot fungi, Gloeophyllum trabeum and Postia placenta, following procedures described in AWPA Standard E22 and E10. The penetration of MßCD-EOs complexes in wood was confirmed by fluorescence microscopic analysis after the selective dyeing of EOs encapsulated in MßCD. In comparison to the control wood samples, MßCD-EOs complexes treated wood exhibited a significant reduction in the mass loss from 16-36% to 2-18%, accompanied by improvement in radial compression strength loss from 81-92% to 29-67% after four-week fungi exposure.


Assuntos
Antifúngicos , Basidiomycota/crescimento & desenvolvimento , Óleos Voláteis , Madeira/microbiologia , beta-Ciclodextrinas , Antifúngicos/química , Antifúngicos/farmacologia , Óleos Voláteis/química , Óleos Voláteis/farmacologia , beta-Ciclodextrinas/química , beta-Ciclodextrinas/farmacologia
17.
BMC Biotechnol ; 20(1): 2, 2020 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-31910834

RESUMO

BACKGROUND: Cellulosic biomass degradation still needs to be paid more attentions as bioenergy is the most likely to replace fossil energy in the future, and more evaluable cellulolytic bacteria isolation will lay a foundation for this filed. Qinling Mountains have unique biodiversity, acting as promising source of cellulose-degrading bacteria exhibiting noteworthy properties. Therefore, the aim of this work was to find potential cellulolytic bacteria and verify the possibility of the cloning of cellulases from the selected powerful bacteria. RESULTS: In present study, 55 potential cellulolytic bacteria were screened and identified from the rotten wood of Qinling Mountains. Based on the investigation of cellulase activities and degradation effect on different cellulose substrates, Bacillus methylotrophicus 1EJ7, Bacillus subtilis 1AJ3 and Bacillus subtilis 3BJ4 were further applied to hydrolyze wheat straw, corn stover and switchgrass, and the results suggested that B. methylotrophicus 1EJ7 was the most preponderant bacterium, and which also indicated that Bacillus was the main cellulolytic bacteria in rotten wood. Furthermore, scanning electron microscopy (SEM) and X-ray diffraction analysis of micromorphology and crystallinity of wheat straw also verified the significant hydrolyzation. With ascertaining the target sequence of cellulase ß-glucosidase (243 aa) and endoglucanase (499 aa) were successfully heterogeneously cloned and expressed from B. methylotrophicus 1EJ7, and which performed a good effect on cellulose degradation with enzyme activity of 1670.15 ± 18.94 U/mL and 0.130 ± 0.002 U/mL, respectively. In addition, based on analysis of amino acid sequence, it found that ß-glucosidase were belonged to GH16 family, and endoglucanase was composed of GH5 family catalytic domain and a carbohydrate-binding module of CBM3 family. CONCLUSIONS: Based on the screening, identification and cellulose degradation effect evaluation of cellulolytic bacteria from rotten wood of Qinling Mountains, it found that Bacillus were the predominant species among the isolated strains, and B. methylotrophicus 1EJ7 performed best on cellulose degradation. Meanwhile, the ß-glucosidase and endoglucanase were successfully cloned and expressed from B. methylotrophicus for the first time, which provided new materials of both strain and the recombinant enzymes for the study of cellulose degradation and its application in industry.


Assuntos
Bacillus/classificação , Celulases/genética , Triticum/química , Madeira/microbiologia , Bacillus/enzimologia , Bacillus/genética , Bacillus/isolamento & purificação , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biomassa , Celulases/metabolismo , Clonagem Molecular , Hidrólise , Microscopia Eletrônica de Varredura , Difração de Raios X
18.
ISME J ; 14(2): 380-388, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31628441

RESUMO

Saprotrophic cord-forming basidiomycetes, with their mycelial networks at the soil/litter interface on the forest floor, play a major role in wood decomposition and nutrient cycling/relocation. Many studies have investigated foraging behaviour of their mycelium, but there is little information on their intelligence. Here, we investigate the effects of relative size of inoculum wood and new wood resource (bait) on the decision of a mycelium to remain in, or migrate from, inoculum to bait using Phanerochaete velutina as a model. Experiments allowed mycelium to grow from an inoculum across the surface of a soil microcosm where it encountered a new wood bait. After colonisation of the bait, the original inoculum was moved to a tray of fresh soil to determine whether the fungus was still able to grow out. This also allowed us to test the mycelium's memory of growth direction. When inocula were transferred to new soil, there was regrowth from 67% of the inocula, and a threshold bait size acted as a cue for the mycelium's decision to migrate for a final time, rather than a threshold of relative size of inoculum: bait. There was greater regrowth from the side that originally faced the new bait, implying memory of growth direction.


Assuntos
Micélio/crescimento & desenvolvimento , Microbiologia do Solo , Florestas , Phanerochaete , Madeira/microbiologia
19.
J Biotechnol ; 308: 35-39, 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31778732

RESUMO

Heterologous production of fungal ligninolytic cocktails is challenging due to the low yields of catalytically active lignin modifying peroxidases. Production using a natural system, such as a wood-rotting fungus, is a promising alternative if specific or preferential induction of the ligninolytic activities could be achieved. Using transcriptomics, gene expression of the white-rot Dichomitus squalens during growth on mixtures of aromatic compounds, with ring structures representing the two major lignin sub-units, was compared to a wood substrate. Most of the genes encoding lignin modifying enzymes (laccases and peroxidases) categorised as highly or moderately expressed on wood were expressed similarly on aromatic compounds. Higher expression levels of a subset of manganese and versatile peroxidases was observed on di- compared to mono-methoxylated aromatics. The expression of polysaccharide degrading enzymes was lower on aromatic compounds compared to wood, demonstrating that the induction of lignin modifying enzymes became more specific. This study suggests potential for aromatic waste streams, e.g. from lignocellulose pretreatment, to produce a lignin-specific enzyme cocktail from D. squalens or other white-rot fungi.


Assuntos
Proteínas Fúngicas/genética , Perfilação da Expressão Gênica/métodos , Hidrocarbonetos Aromáticos/farmacologia , Polyporaceae/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Hidrocarbonetos Aromáticos/química , Lacase/genética , Lignina/metabolismo , Peroxidases/genética , Polyporaceae/metabolismo , Madeira/química , Madeira/microbiologia
20.
J Agric Food Chem ; 68(1): 301-314, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31820631

RESUMO

Xylooligosaccharides (XOS) from woody biomass were evaluated as a substrate for secondary lactic acid bacteria (LAB) fermentation in sour beer production. XOS were extracted from birch (Betula pubescens) and added to beer to promote the growth of Lactobacillus brevis BSO 464. Growth, pH, XOS degradation, and metabolic products were monitored throughout fermentations, and the final beer was evaluated sensorically. XOS were utilized, metabolic compounds were produced (1800 mg/L lactic acid), and pH was reduced from 4.1 to 3.6. Secondary fermentation changed sensory properties significantly, and the resulting sour beer was assessed as similar to a commercial reference in multiple attributes, including acidic taste. Overall, secondary LAB fermentation induced by wood-derived XOS provided a new approach to successfully produce sour beer with reduced fermentation time (from 1-3 years to 4 weeks). The presented results demonstrate how hemicellulosic biomass can be valorized for beverage production and to obtain sour beer with improved process control.


Assuntos
Cerveja/análise , Microbiologia de Alimentos/métodos , Glucuronatos/metabolismo , Lactobacillales/metabolismo , Oligossacarídeos/metabolismo , Extratos Vegetais/metabolismo , Madeira/química , Cerveja/microbiologia , Betula/química , Betula/metabolismo , Betula/microbiologia , Fermentação , Humanos , Concentração de Íons de Hidrogênio , Lactobacillales/crescimento & desenvolvimento , Paladar , Madeira/metabolismo , Madeira/microbiologia
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