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1.
Sci Total Environ ; 912: 168772, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38008316

RESUMO

Satellite-based land cover mapping plays an important role in understanding changes in ecosystems and biodiversity. There are global land cover products available, however for region specific studies of drivers of infectious disease patterns, these can lack the spatial and thematic detail or accuracy required to capture key ecological processes. To overcome this, we produced our own Landsat derived 30 m maps for three districts in India's Western Ghats (Wayanad, Shivamogga and Sindhudurg). The maps locate natural vegetation types, plantation types, agricultural areas, water bodies and settlements in the landscape, all relevant to functional resource use of species involved in infectious disease dynamics. The maps represent the mode of 50 classification iterations and include a spatial measure of class stability derived from these iterations. Overall accuracies for Wayanad, Shivamogga and Sindhudurg are 94.7 % (SE 1.2 %), 88.9 % (SE 1.2 %) and 88.8 % (SE 2 %) respectively. Class classification stability was high across all three districts and the individual classes that matter for defining key interfaces between human habitation, forests, crop, and plantation cultivation, were generally well separated. A comparison with the 300 m global ESA CCI land cover map highlights lower ESA CCI class accuracies and the importance of increased spatial resolution when dealing with complex landscape mosaics. A comparison with the 30 m Global Forest Change product reveals an accurate mapping of forest loss and different dynamics between districts (i.e., Forests lost to Built-up versus Forests lost to Plantations), demonstrating an interesting complementarity between our maps and the % tree cover Global Forest Change product. When studying infectious disease responses to land use change in tropical forest ecosystems, we recommend using bespoke land cover/use classifications reflecting functional resource use by relevant vectors, reservoirs, and people. Alternatively, global products should be carefully validated with ground reference points representing locally relevant habitats.


Assuntos
Doenças Transmissíveis , Ecossistema , Humanos , Conservação dos Recursos Naturais , Florestas , Biodiversidade
2.
Food Res Int ; 162(Pt A): 111935, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36461193

RESUMO

Fungi and oomycetes found in vineyards cause diseases such as powdery and downy mildew. Consequently, conventional and alternative agronomical practices are widely used prior to harvest to protect grapes. Alternative products are considered more eco-friendly and environmentally sustainable in comparison to conventional chemical products. However, the effect of these alternative products on yeast ecology, from the vineyard to the winery, is poorly understood. This study compared the effect of alternative and conventional chemical antifungal compounds (copper and sulphur based) on grapes' mycobiota in the vineyard and during subsequent winery fermentation using culture-dependent and -independent approaches. Culture-dependent data indicated a treatment-dependent effect on the load and diversity of yeast populations on grapes. It was found that the population of Hanseniaspora uvarum was higher on grapes previously treated with laminarin and copper, compared to the other levels registered on grapes previously treated with the rest of antifungal products tested in this study (including the untreated and conventional treatment controls). Concerning, wine quality, the chemical composition was not correlated to the application of antifungal treatment in the vineyard. Understanding the effect of different antifungal products on grape and wine microbial communities may help in setting up guidelines for wine grape production. These guidelines, can be used to guarantee quality in the pursuit of a sustainable competitive advantage in the market.


Assuntos
Fungicidas Industriais , Vitis , Fazendas , Fungicidas Industriais/farmacologia , Antifúngicos , Cobre , Biodiversidade
3.
Food Res Int ; 157: 111265, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35761577

RESUMO

Brazilian artisanal cheeses date from the first Portuguese settlers and evolved via local factors, resulting in unique products that are now part of the patrimony and identity of different Brazilian regions. In this study, we combined several culture-independent approaches, including 16S/ITS metagenetics, assembly- and deep profiling-metagenomics to characterize the originality of the microbiota of five varieties of Brazilian artisanal cheeses from the South and Southeast regions of Brazil. Their core microbiota contained mainly lactic acid bacteria (LAB), of which Lactococcus lactis subsp. lactis was the most frequent, followed by Streptococcus thermophilus in the South region. Moreover, several samples from the Southeast region contained, as dominant LAB, two other food Streptococci belonging to a new species of the salivarius group and S. infantarius. Rinds of samples from the Southeast region were dominated by the halotolerant bacterium Corynebacterium variabile, and the yeasts Diutina catenulata, followed by Debaryomyces hansenii and Kodamaea ohmeri. Rinds from the South region contained mainly LAB due to their short ripening time, and the predominant yeast was D. hansenii. Phylogenomic analysis based on L. lactis metagenome-assembled genomes (MAGs) showed that most Brazilian strains are closely related and form a different clade from those whose genomes are available at this time, indicating that they belong to a specific group. Lastly, functional analysis showed that S. infantarius acquired a âˆ¼ 26 kb DNA fragment from S. thermophilus starter strains that carry the LacSZ system, allowing fast lactose assimilation, an adaptation advantage for growth in milk. Finally, our study identified several areas of concern, such as the presence of somatic cell DNA and high levels of antibiotic resistance genes in several cheese microbiota, suggesting that milk from diseased animals may still be used occasionally. Overall, the data from this study highlight the potential value of the traditional and artisanal cheese production network in Brazil, and provide a metagenomic-based scheme to help manage this resource safely.


Assuntos
Queijo , Lactobacillales , Lactococcus lactis , Animais , Biodiversidade , Brasil , Queijo/análise , Microbiologia de Alimentos , Lactobacillales/genética , Lactococcus lactis/genética , Metagenômica , Streptococcus thermophilus/genética , Leveduras
4.
Arch Microbiol ; 203(1): 153-162, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32780151

RESUMO

Biodiversity of native yeasts, especially in winemaking, has hidden potential. In order to use the value of non-Saccharomyces strains in wine production and to minimise the possibility of its deterioration, it is necessary to thoroughly study the yeast cultures present on grape fruits and in grape must, as well as their metabolic properties. The aim of the study was to characterise the yeast microbiota found during spontaneous fermentation of grape musts obtained from grape varieties 'Rondo', 'Regent' and 'Johanniter'. Grapes from two vineyards (Srebrna Góra and Zadora) located in southern Poland were used for the research. Succession of subsequent groups of yeasts was observed during the process. Metschnikowia pulcherrima yeasts were identified both at the beginning and the end of the process. Hanseniaspora uvarum, Wickerhamomyces onychis and Torulaspora delbrueckii strains were also identified during the fermentation. Torulaspora delbrueckii and Wickerhamomyces onychis strains were identified only in grape musts obtained from grapes of the Zadora vineyard. These strains may be characteristic of this vineyard and shape the identity of wines formed in it. Our research has provided specific knowledge on the biodiversity of yeast cultures on grapes and during their spontaneous fermentation. The research results presented indicate the possibility of using native strains for fermentation of grape musts, allowing to obtain a product with favourable chemical composition and sensory profile.


Assuntos
Biodiversidade , Fermentação , Microbiologia de Alimentos , Vitis/microbiologia , Leveduras/classificação , Clima , Hanseniaspora/isolamento & purificação , Hanseniaspora/fisiologia , Metschnikowia/isolamento & purificação , Metschnikowia/fisiologia , Polônia , Saccharomycetales/isolamento & purificação , Saccharomycetales/fisiologia , Torulaspora/isolamento & purificação , Torulaspora/fisiologia , Vinho/microbiologia , Leveduras/isolamento & purificação , Leveduras/fisiologia
5.
Int J Food Microbiol ; 339: 108987, 2021 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-33321431

RESUMO

Bacterial and fungal population dynamics in cider for distillation have so far been explored by culture-dependant methods. Cider for distillation can be produced by the spontaneous fermentation of apples that do not undergo any intervention during the process. In this study, cider microbiomes extracted from six tanks containing ciders for distillation from four producers in Normandy were characterized at three main stages of the fermentation process: fermentation Initiation (I), end of the alcoholic Fermentation (F) and end of the Maturation period (M). Cider samples were subjected to Illumina MiSeq sequencing (rRNA 16S V1-V3 and ITS1 region targeting) to determine bacterial and fungal communities. Yeasts (YGC), Zymomonas (mZPP) and lactic acid bacteria selective media (mMRS, mMLO, mPSM) were also used to collect 807 isolates. Alcoholic levels, glycerol, sugar content (glucose, fructose and sucrose), pH, total and volatile acidity, nitrogen, malic and lactic acid contents were determined at all sampling points. Alpha diversity indexes show significant differences (p < 0.05) in microbial populations between I, F and M. Fungal communities were characterized by microorganisms from the environment and phytopathogens at I followed by the association of yearsts with alcoholic fermentation like Saccharomyces and non-Saccharomyces yeasts (Hanseniaspora, Candida). A maturation period for cider leads to an increase of the Dekkera/Brettanomyces population, which is responsible for off-flavors in cider for all producers. Among bacterial communities, the genera community associated to malolactic fermentation (Lactobacillus sp., Leuconostoc sp., Oenococcus sp.) was the most abundant at F and M. Acetic acid bacteria such as Acetobacter sp., Komagataeibacter sp. and Gluconobacter sp. were also detected during the process. Significant differences (p < 0.05) were found in fungal and bacterial populations between the four producers and during the fermentation process. The development of microorganisms associated with cider spoilage such as Zymomonas mobilis, Lactobacillus collinoides or Brettanomyces/Dekkera sp. was anticipated by a metagenomic approach. The monitoring of microbial diversity via high throughput sequencing combined with physical-chemical analysis is an interesting approach to improve the fermentation performance of cider for distillation and therefore, the quality of Calvados.


Assuntos
Bebidas Alcoólicas/microbiologia , Fenômenos Fisiológicos Bacterianos , Biodiversidade , Destilação , Fungos/fisiologia , Bactérias/genética , DNA Espaçador Ribossômico/genética , Fermentação , Malus , RNA Ribossômico 16S/genética
6.
Adv Appl Microbiol ; 111: 89-121, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32446413

RESUMO

Vitis vinifera flowers and grape fruits are one of the most interesting ecosystem niches for native yeasts development. There are more than a 100 yeast species and millions of strains that participate and contribute to design the microbial terroir. The wine terroir concept is understood when grape and wine micro-regions were delimited by different quality characteristics after humans had been growing vines for more than 10,000 years. Environmental conditions, such as climate, soil composition, water management, winds and air quality, altitude, fauna and flora and microbes, are considered part of the "terroir" and contribute to a unique wine style. If "low input winemaking" strategies are applied, the terroir effect will be expected to be more authentic in terms of quality differentiation. Interestingly, the role of the microbial flora associated with vines was very little study until recently when new genetic technologies for massive species identification were developed. These biotechnologies allowed following their environmental changes and their effect in shaping the microbial profiles of different wine regions. In this chapter we explain the interesting positive effects on flavor diversity and wine quality obtained by using "friendly" native yeasts that allowed the microbial terroir flora to participate and contribute during fermentation.


Assuntos
Biodiversidade , Paladar , Vinho/microbiologia , Leveduras/metabolismo , Ecossistema , Fermentação , Microbiologia de Alimentos , Microbiota , Vitis
7.
Med Sci Monit ; 26: e920879, 2020 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-31986127

RESUMO

BACKGROUND Debaryomyces hansenii exhibits a therapeutic effect on antibiotic-associated diarrhea (AAD) by promoting the growth of beneficial intestinal bacteria. Previous research has reported that AAD involves not only dysbacteriosis but also dysfunction of the activity of intestinal enzymes (such as lactase). Enzyme activities can be influenced by many other factors, such as gene expression. The present study showed that D. hansenii has a curative effect on AAD at the lactase gene level. MATERIAL AND METHODS The effect of D. hansenii on the lactase gene from intestinal bacteria in AAD mice was investigated. The diarrhea model was established with a gentamycin sulfate and cefradine capsule mixture. The antibiotic mixture (23.33 mL·kg⁻¹·day⁻¹) was intragastrically administered for 5 days. Subsequently, half of the diarrhea mice were treated with D. hansenii twice a day for 3 days while the other mice were intragastrically administered with the same volume of distilled water. Next, the intestinal contents were collected, and metagenomic DNA was extracted for high-throughput sequencing analysis. RESULTS The Chao1 and Shannon indices decreased significantly following treatment with D. hansenii (P<0.01 and P<0.05, respectively). Moreover, the clusters in the D. hansenii group mice were quite different from those in the normal group mice and model group mice. Following treatment with D. hansenii, the quantity of lactase genes in Enterobacter sp. 638 and Modestobacter increased markedly, and the richness of intestinal bacterial lactase genes in Fretibacterium recovered. CONCLUSIONS D. hansenii altered the lactase-producing bacterial community structure and promoted the growth of several critical lactase-producing bacteria, such as Enterobacter sp. 638 and Modestobacter.


Assuntos
Antibacterianos/uso terapêutico , Bactérias/genética , Biodiversidade , Diarreia/tratamento farmacológico , Diarreia/microbiologia , Genes Bacterianos , Intestinos/microbiologia , Lactase/genética , Animais , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Sequência de Bases , Feminino , Masculino , Camundongos
8.
PLoS One ; 14(12): e0225802, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31809511

RESUMO

AIM: The current study aimed to investigate the effects of Debaryomyces hansenii on the diversity of bacterial lactase gene in the intestinal mucosa of antibiotic-associated diarrhea (AAD) mice. METHODS: Eighteen mice were randomly divided into three groups (6 mice per group): healthy control group, diarrhea model group and D. hansenii treatment group. The antibiotic-associated diarrhea model was established by intragastric administration with a mixture of cephradine and gentamicin sulfate (23.33 mL·kg-1·d-1) twice a day for 5 days continuously. After establishing the AAD model, the mice in the D. hansenii treatment group were gavaged with D. hansenii for three days, while other groups were gavaged with distilled water. Then, the intestinal mucosa of all three groups was collected and DNA was extracted in an aseptic environment for the following analysis. RESULTS: The difference in the richness and homogeneity of the bacterial lactase gene among all samples were inapparent, as the difference in the Chao1, ACE, Simpson and Shannon indices among the three groups were insignificant (P>0.05). NMDS analysis also showed that the distance of the samples among the three groups was unobvious. Furthermore, the bacterial lactase gene in the mucosa mainly originated from Actinobacteria, Firmicutes and Proteobacteria. Compared with the healthy control group, the abundance of lactase genes originating from Cupriavidus, Lysobacter, Citrobacter, Enterobacter and Pseudomonas was increased in the D. hansenii treatment group, while the lactase gene from Acidovorax and Stenotrophomonas decreased (p < 0.01 or p < 0.05) in the diarrhea model group and the D. hansenii treatment group. CONCLUSION: D. hansenii was capable of improving the growth of some key lactase-producing bacteria like Deinococcus, Cupriavidus and Lysobacter for treating AAD.


Assuntos
Antibacterianos/efeitos adversos , Diarreia/induzido quimicamente , Diarreia/microbiologia , Genes Bacterianos , Variação Genética , Mucosa Intestinal/microbiologia , Lactase/genética , Saccharomycetales/fisiologia , Animais , Sequência de Bases , Biodiversidade , Feminino , Masculino , Camundongos , Filogenia , Análise de Componente Principal
9.
J Fish Biol ; 95(4): 1046-1060, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31304599

RESUMO

The extraordinary species diversity of the Neotropical freshwater fish fauna is world renown. Yet, despite rich species diversity, taxonomic and genetic resources for its Cerrado ichthyofauna remain poorly developed. We provide a reference library of 149 DNA barcodes for 39 species/lineages of Cerrado headwater stream fishes from the Brazilian Distrito Federal and nearby areas and test the utility of distance-based criteria, tree-based criteria and minibarcodes for specimen identification. Mean Kimura 2-parameter genetic distances within species to orders ranged 1·8-12·1%. However, mean intraspecific v. congeneric-interspecific distances (0·9-1·3%) overlapped extensively and distance-based barcoding failed to achieve correct identifications due to c. 4-12·1% error rates and 19·5% ambiguous identifications related to the presence of singletons. Overlap was reduced and best-match success rates improved drastically to 83·5% when Characidium barcodes representing potential misidentifications or undescribed species were removed. Tree-based monophyly criteria generally performed similarly to distance methods, correctly differentiating up to c. 85% of species/lineages despite neighbour-joining and Bayesian tree errors (random lineage-branching events, long-branch attraction). Five clusters (Ancistrus aguaboensis, Characidium spp., Eigenmannia trilineata, Hasemania hanseni and Hypostomus sp. 2) exhibited deep intraspecific divergences or para-/polyphyly and multiple Barcode Index Number assignments indicative of putative candidate species needing taxonomic re-examination. Sliding-window analyses also indicated that a 200 bp minibarcode region performed just as well at specimen identification as the entire barcode gene. Future DNA barcoding studies of Distrito Federal-Cerrado freshwater fishes will benefit from increased sampling coverage, as well as consideration of minibarcode targets for degraded samples and next-generation sequencing.


Assuntos
Distribuição Animal , Código de Barras de DNA Taxonômico , Peixes/genética , Animais , Teorema de Bayes , Biodiversidade , Brasil , Complexo IV da Cadeia de Transporte de Elétrons/genética , Peixes/fisiologia , Biblioteca Gênica , Filogenia , Rios , Especificidade da Espécie
10.
Fungal Biol ; 123(7): 507-516, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31196520

RESUMO

In the present study, we surveyed the distribution and diversity of fungal assemblages associated with 10 species of marine animals from Antarctica. The collections yielded 83 taxa from 27 distinct genera, which were identified using molecular biology methods. The most abundant taxa were Cladosporium sp. 1, Debaryomyces hansenii, Glaciozyma martinii, Metschnikowia australis, Pseudogymnoascus destructans, Thelebolus cf. globosus, Pseudogymnoascus pannorum, Tolypocladium tundrense, Metschnikowia australis, and different Penicillium species. The diversity, richness, and dominance of fungal assemblages ranged among the host; however, in general, the fungal community, which was composed of endemic and cold-adapted cosmopolitan taxa distributed across the different sites of Antarctic Peninsula, displayed high diversity, richness, and dominance indices. Our results contribute to knowledge about fungal diversity in the marine environment across the Antarctic Peninsula and their phylogenetic relationships with species that occur in other cold, temperate, and tropical regions of the World. Additionally, despite their extreme habitats, marine Antarctic animals shelter cryptic and complex fungal assemblages represented by endemic and cosmopolitan cold-adapted taxa, which may represent interesting models to study different symbiotic associations between fungi and their animal hosts in the extreme conditions of Antarctica.


Assuntos
Organismos Aquáticos/microbiologia , Biodiversidade , Fungos/classificação , Fungos/crescimento & desenvolvimento , Micobioma/fisiologia , Filogenia , Animais , Regiões Antárticas , Extremófilos/classificação , Extremófilos/genética , Extremófilos/crescimento & desenvolvimento , Extremófilos/isolamento & purificação , Fungos/genética , Fungos/isolamento & purificação
11.
Food Microbiol ; 80: 62-69, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30704597

RESUMO

The effect of high pressure processing (HPP) on the microbiota of ripened Iberian ham of different water activity, salt concentration and intramuscular fat content was investigated before and after a 5-month refrigeration period. At the beginning of the refrigeration period, the only significant effects of chemical composition were those of water activity on psychrotrophs and Micrococcaceae in untreated hams, and of the salt-in-lean ratio on lactic acid bacteria in HPP-treated hams. At the end of the refrigeration period, the only significant effect was that of intramuscular fat content on moulds and yeasts in HPP-treated samples. All microbial groups were significantly affected by HPP, with reductions ranging from 1.7 to 2.0 log cycles after treatment. A significant recovery of all microbial groups took place in HPP-treated hams during the refrigeration period, with increases ranging from 0.5 to 1.1 log cycles. In spite of this recovery, microbial levels in HPP-treated hams remained significantly lower than in untreated hams. Staphylococcus accounted for 93.4% of Iberian ham bacterial isolates, with S. equorum as the most abundant species. Representatives of the Tetragenococcus, Carnobacterium and Streptomyces genera, not previously reported in dry-cured ham, were also isolated. Most of the yeast isolates (75.0%) were identified as Debaryomyces hansenii.


Assuntos
Manipulação de Alimentos/métodos , Microbiologia de Alimentos , Carne/microbiologia , Microbiota/genética , Refrigeração , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Biodiversidade , Gorduras na Dieta/análise , Conservação de Alimentos , Alimentos em Conserva/análise , Alimentos em Conserva/microbiologia , Fungos/classificação , Fungos/genética , Fungos/isolamento & purificação , Carne/análise , Tipagem Molecular , Pressão , Cloreto de Sódio na Dieta/análise , Suínos , Água/análise
12.
Int J Food Microbiol ; 290: 1-14, 2019 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-30278370

RESUMO

Modern day winemaking often involves the addition of sulfur dioxide (SO2) at crush to act as both an antioxidant and an antimicrobial agent. While the effects of SO2 on microbial communities and particularly on spoilage microorganisms has been well-studied, the advent of culture-independent molecular technologies, such as Illumina sequencing, allows the subject to be re-visited in a new context. High-throughput amplicon sequencing allows for a more thorough evaluation of microbial communities, as thousands of microbial sequences per sample can be identified and even rare microorganisms can be studied. This research investigated whether the addition of different levels of SO2 at crush (0, 20, or 40 mg/L) would affect the composition of fungal and bacterial communities, as well as the sensory attributes of the resulting wines. Samples were taken from uninoculated fermentations of Pinot gris and analyzed via high-throughput amplicon sequencing using the Illumina MiSeq platform. Yeast relative abundance and overall fungal community composition differed among the SO2 additions. Notably, a Hanseniaspora yeast appeared in all treatments and persisted until the end of alcoholic fermentation, although its relative abundance was significantly higher in the fermentations to which low or no SO2 had been added. Two key wine sensory attributes (citrus aroma and pome fruit flavor) differed among the SO2 treatments. This research provides an in-depth look into the fungal and bacterial communities during alcoholic fermentation and gives a better understanding of the microbial community response to SO2 additions during the crush period.


Assuntos
Microbiota/efeitos dos fármacos , Dióxido de Enxofre/farmacologia , Vinho/microbiologia , Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/genética , Biodiversidade , Fermentação , Odorantes/análise , Leveduras/efeitos dos fármacos , Leveduras/genética
13.
Int J Food Microbiol ; 289: 223-230, 2019 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-30391797

RESUMO

Yeast-like fungi and yeasts residing on carposphere of withered grapes for Italian passito wine production have been scarcely investigated. In the present study, isolates from single berries, both sound and damaged, of Nosiola, Corvina and Garganega varieties were analyzed at the end of the withering process. Great variation of cell concentration among single berries was observed. In sound berries, yeast-like fungi were significantly more frequent than yeasts. Species identification of isolates was carried out by BLAST comparative analysis on gene databases and phylogenetic approach. All yeast-like fungi isolates belonged to Aureobasidium pullulans. They displayed different culture and physiological characteristics and inhibitory capacity against phytopathogenic fungi. Moreover, PCR profile analysis revealed high genotypic similarity among these strains. A total of 35 species were recognized among yeast isolates. Ascomycetes prevailed over basidiomycetes. To the best of our knowledge, Naganishia onofrii and Rhodosporidiobolus odoratus were identified for the first time among yeasts isolated from grapes, must or wine. Hanseniaspora uvarum and Starmerella bacillaris were the most frequent species. Most species were found only in one grape variety (nine in Nosiola, 10 in Corvina and five in Garganega). The sanitary state of withered grapes could have an important impact on the structure of these epiphytic populations.


Assuntos
Fungos/fisiologia , Vitis/microbiologia , Leveduras/fisiologia , Biodiversidade , Frutas/microbiologia , Fungos/classificação , Fungos/genética , Fungos/isolamento & purificação , Genes Fúngicos/genética , Genótipo , Itália , Filogenia , Leveduras/classificação , Leveduras/genética , Leveduras/isolamento & purificação
14.
Fungal Biol ; 122(7): 668-676, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29880202

RESUMO

We investigated the yeast species associated with rotting wood samples obtained from Brazilian ecosystems, with a special focus on cellobiose-fermenting species. About 647 yeast strains were isolated from rotting wood samples collected from the areas of Atlantic rainforest, Cerrado, and Amazonian forest. Eighty-six known species and 47 novel species of yeasts were isolated. Candida boidinii, Cyberlindnera subsufficiens, Meyerozyma guilliermondii, Schwanniomyces polymorphus, Candida natalensis, and Debaryomyces hansenii were the most frequently isolated species. Among the cellobiose-fermenting yeasts, 14 known and three novel yeast species were identified. Scheffersomyces queiroziae, Sc. amazonensis, Yamadazyma sp.1, Hanseniaspora opuntiae, C. jaroonii, and Candida tammaniensis were the main ethanol-producing yeasts. These species also produced an intracellular ß-glucosidase responsible for cellobiose hydrolysis. In fermentation assays using a culture medium containing 50 g L-1 cellobiose, ethanol production was observed in all cases; Sc. queiroziae and Sc. amazonensis showed the highest yield, efficiency, and productivity. Candida jaroonii and Yamadazyma sp.1 strains also showed high efficiency in cellobiose fermentation, while C. tammaniensis and H. opuntiae strains produced low amounts of ethanol. This study shows the potential of rotting wood samples from Brazilian ecosystems as a source of yeasts, including new species as well as those with promising biotechnological properties.


Assuntos
Biodiversidade , Celobiose/metabolismo , Leveduras/fisiologia , Brasil , Ecossistema , Fermentação , Madeira/microbiologia , Leveduras/genética , Leveduras/isolamento & purificação , beta-Glucosidase/metabolismo
15.
Folia Microbiol (Praha) ; 63(6): 677-684, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29736893

RESUMO

Identification of yeasts isolated from apple juices of two cider houses (one located in a plain area and one in an alpine area) was carried out by culture-based method. Wallerstein Laboratory Nutrient Agar was used as medium for isolation and preliminary yeasts identification. A total of 20 species of yeasts belonging to ten different genera were identified using both BLAST algorithm for pairwise sequence comparison and phylogenetic approaches. A wide variety of non-Saccharomyces species was found. Interestingly, Candida railenensis, Candida cylindracea, Hanseniaspora meyeri, Hanseniaspora pseudoguilliermondii, and Metschnikowia sinensis were recovered for the first time in the yeast community of an apple environment. Phylogenetic analysis revealed a better resolution in identifying Metschnikowia and Moesziomyces isolates than comparative analysis using the GenBank or YeastIP gene databases. This study provides important data on yeast microbiota of apple juice and evidenced differences between two geographical cider production areas in terms of species composition.


Assuntos
Biodiversidade , Sucos de Frutas e Vegetais/microbiologia , Malus/microbiologia , Leveduras/isolamento & purificação , Leveduras/metabolismo , Meios de Cultura/metabolismo , Fermentação , Microbiologia de Alimentos , Frutas/metabolismo , Frutas/microbiologia , Malus/metabolismo , Filogenia , Leveduras/classificação , Leveduras/genética
16.
Folia Microbiol (Praha) ; 63(6): 685-693, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29752627

RESUMO

The study of grape microflora is of interest when autochthonous yeasts, which are related to typical wine characteristics, are intended to be used in winemaking. The election of matrix-assisted laser desorption-ionization time-of-flight mass spectrometry (MALDI-TOF MS) as the first method for yeast identification was based on its accuracy and rapidity compared to alternative laboratory protocols for identification. The aims of this study are to consolidate the MALDI-TOF MS Supplementary database for environmental yeasts already constructed, to expand it through the addition of standard spectra of not included yeast species, and to discuss the grape microflora encountered in Southern Brazil. A total of 358 strains, isolated from grape berries, were submitted to protein profiling employing Biotyper and Supplementary database. Molecular biology techniques were used as alternatives to identify 6.4% of strains not promptly designated by protein profiling. These strains corresponded to the species Candida californica, Zygoascus meyerae, Candida akabanensis, Candida azyma, and Hanseniaspora vineae. The MALDI-TOF MS spectra of the identified species were added to Supplementary database. The presented results strengthen the need for further expansion of the mass spectra database to broaden its microbiological application.


Assuntos
Biodiversidade , Vitis/microbiologia , Leveduras/isolamento & purificação , Brasil , Bases de Dados Genéticas , Frutas/microbiologia , Filogenia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Vinho/análise , Leveduras/classificação , Leveduras/genética
17.
Int J Food Microbiol ; 281: 36-46, 2018 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-29807290

RESUMO

The main losses in viticulture around the world are normally associated with rotten grapes affecting both the chemical composition and the grape microbiota that later might affect the alcoholic fermentation. We analyzed the population in musts obtained from sour rotten, botrytized and healthy Macabeo grapes and the population dynamics during the spontaneous alcoholic fermentation by culture dependent and various culture independent methods including, for the first time, qPCR and massive sequencing. Grape health state affected the fermentation kinetics and also the microbial diversity and composition. Unexpectedly, the fermentation proceeded the fastest in the rotten must followed by the healthy and the botrytized grapes. As in previous studies, plate cell counts and qPCR results confirmed the increase in the number of both bacteria and fungi in the musts from damaged grapes. Massive sequencing detected higher biodiversity than the other techniques at each stage, with Saccharomyces and Oenococcus found already in the grape must. Hanseniaspora osmophila replaced to Hanseniaspora uvarum as the predominant yeast during the mid-fermentation stage for both damaged grapes. Furthermore, musts and beginning of fermentation from rotten and botrytized grapes consistently had a higher presence of the fungi Zygosaccharomyces, Penicillium and Aspergillus while high abundance of Botrytis were observed just for botrytized grapes. As expected, the acetic acid bacteria number increased in musts from rotten and botrytized grapes, mostly due to changes in proportion of the genus Gluconoacetobacter which remained more abundant during damaged grapes fermentation than during healthy ones. Interestingly, the presence of Oenococcus oeni at the end of the alcoholic fermentation was strongly affected by the health status of the grapes.


Assuntos
Botrytis/fisiologia , Microbiologia de Alimentos , Microbiota/fisiologia , Vitis/microbiologia , Biodiversidade , Fermentação , Vinho/microbiologia , Leveduras/classificação , Leveduras/fisiologia
18.
Int J Food Microbiol ; 266: 42-51, 2018 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-29175763

RESUMO

Culture-dependent and culture-independent strategies were applied to investigate the microbiota of autumn undamaged and damaged berries, winter berries and ice wine must samples of Grüner Veltliner (Veltlínske zelené) from Small Carpathian wine-producing region. One hundred twenty-six yeasts and 242 bacterial strains isolated from several microbiological media (YPD, PDA, R2A, GYC, MRS and MRS-T) were clustered by ITS-PCR and subsequent Qiaxcel electrophoresis. Representatives of each cluster were identified by sequencing. The extracellular hydrolytic properties and intracellular activities of esterase and ß-glucosidase of isolates were assayed. The culture-independent approach permitted the analysis of extracted DNA and RNA coupling DGGE fingerprinting with construction of clone libraries (bacterial and fungal; DGGE-cloning). The combination of the two approaches provided comprehensive data that evidenced the presence of a complex microbiota in each analyzed sample. RNA and DNA analyses facilitated differentiation of living microorganisms from the entire microbiota. Diverse microbial communities colonized the autumn and winter berries. Generally, the combination of results obtained by the methods suggested that the must samples contained mainly Saccharomyces cerevisiae, Metschnikowia spp., Hanseniaspora uvarum, Lactococcus lactis and Leuconostoc spp. The strains exhibited interesting esterase and ß-glucosidase properties, which are important for aroma formation in wine. Fermentation strategies utilising these microorganisms, could be attempted in the future in order to modulate the ice wine characteristics.


Assuntos
Bactérias/isolamento & purificação , Fermentação , Vinho/microbiologia , Leveduras/isolamento & purificação , Bactérias/genética , Biodiversidade , DNA Espaçador Ribossômico/genética , Esterases/metabolismo , Hanseniaspora/metabolismo , Leuconostoc/genética , Metschnikowia/genética , Reação em Cadeia da Polimerase , Saccharomyces cerevisiae/metabolismo , Leveduras/genética , beta-Glucosidase/metabolismo
19.
World J Microbiol Biotechnol ; 33(12): 211, 2017 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-29134289

RESUMO

Cultivable microbiota presents in a coffee semi-dry processing wastewater treatment plant (WTP) was identified. Thirty-two operational taxonomic units (OTUs) were detected, these being 16 bacteria, 11 yeasts and 4 filamentous fungi. Bacteria dominated the microbial population (11.61 log CFU mL- 1), and presented the highest total diversity index when observed in the WTP aerobic stage (Shannon = 1.94 and Simpson = 0.81). The most frequent bacterial species were Enterobacter asburiae, Sphingobacterium griseoflavum, Chryseobacterium bovis, Serratia marcescens, Corynebacterium flavescens, Acetobacter orientalis and Acetobacter indonesiensis; these showed the largest total bacteria populations in the WTP, with approximately 10 log CFU mL- 1. Yeasts were present at 7 log CFU mL- 1 of viable cells, with Hanseniaspora uvarum, Wickerhamomyces anomalus, Torulaspora delbrueckii, Saturnispora gosingensis, and Kazachstania gamospora being the prevalent species. Filamentous fungi were found at 6 log CFU mL- 1, with Fusarium oxysporum the most populous species. The identified species have the potential to act as a biological treatment in the WTP, and the application of them for this purpose must be better studied.


Assuntos
Bactérias/classificação , Café , Manipulação de Alimentos , Fungos/classificação , Águas Residuárias/microbiologia , Leveduras/classificação , Bactérias/isolamento & purificação , Biodiversidade , Fungos/isolamento & purificação , Microbiota , Filogenia , Leveduras/isolamento & purificação
20.
Parasitology ; 144(11): 1449-1457, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28641604

RESUMO

Blood parasites such as haemogregarines and haemosporidians have been identified in almost all groups of vertebrates and may cause serious damages to their hosts. However, very little is known about biodiversity of these parasites and their effects on some groups of reptiles such as terrapins. Moreover, the information on virulence from blood parasites mixed infection is largely unknown in reptiles. With this aim, we investigated for the first time the prevalence and genetic diversity of blood parasites from one genus of haemoparasitic aplicomplexan (Hepatozoon) in two populations of Spanish terrapins (Mauremys leprosa), a semi-aquatic turtle from southwestern Europe with a vulnerable conservation status. We also examined the association between mixed blood parasite infection and indicators of health of terrapins (body condition, haematocrit values and immune response). Blood parasite infection with Hepatozoon spp was detected in 46·4% of 140 examined terrapins. The prevalence of blood parasites infection differed between populations. We found two different lineages of blood parasite, which have not been found in previous studies. Of the turtles with infection, 5·7% harboured mixed infection by the two lineages. There was no difference in body condition between uninfected, single-infected and mixed-infected turtles, but mixed-infected individuals had the lowest values of haematocrit, thus revealing the negative effects of blood parasite mixed infections. Immune response varied among terrapins with different infection status, where mixed infected individuals had higher immune response than uninfected or single-infected terrapins.


Assuntos
Coccidiose/veterinária , Coinfecção/parasitologia , Eucoccidiida/genética , Variação Genética , Tartarugas/parasitologia , Animais , Biodiversidade , Coccidiose/epidemiologia , Coccidiose/parasitologia , Coinfecção/imunologia , Interações Hospedeiro-Parasita , Prevalência , Tartarugas/imunologia
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