Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 5 de 5
Filter
Add more filters











Publication year range
1.
PLoS One ; 15(12): e0243848, 2020.
Article in English | MEDLINE | ID: mdl-33315910

ABSTRACT

Soil microbiomes, as a primary reservoir for plant colonizing fungi and bacteria, play a major role in determining plant productivity and preventing invasion by pathogenic microorganisms. The use of 16S rRNA and ITS high-throughput amplicon sequencing for analysis of complex microbial communities have increased dramatically in recent years, establishing links between wine specificity and, environmental and viticultural factors, which are framed into the elusive terroir concept. Given the diverse and complex role these factors play on microbial soil structuring of agricultural crops, the main aim of this study is to evaluate how external factors, such as vintage, vineyard location, cultivar and soil characteristics, may affect the diversity of the microbial communities present. Additionally, we aim to compare the influence these factors have on the structuring of bacterial and fungal populations associated with Malbec grapevine rhizosphere with that of the more widespread Cabernet Sauvignon grapevine cultivar. Samples were taken from Malbec and Cabernet Sauvignon cultivars from two different vineyards in the San Juan Province of Argentina. Total DNA extracts from the rhizosphere soil samples were sequenced using Illumina's Miseq technology, targeting the V3-V4 hypervariable 16S rRNA region in prokaryotes and the ITS1 region in yeasts. The major bacterial taxa identified were Proteobacteria, Bacteroidetes and Firmicutes, while the major fungal taxa were Ascomycetes, Basidiomycetes, Mortierellomycetes and a low percentage of Glomeromycetes. Significant differences in microbial community composition were found between vintages and vineyard locations, whose soils showed variances in pH, organic matter, and content of carbon, nitrogen, and absorbable phosphorus.


Subject(s)
Geography , Microbiota , Rhizosphere , Vitis/microbiology , Argentina , Bacteria/classification , Biodiversity , Climate , Fungi/classification , Soil/chemistry
2.
Syst Appl Microbiol ; 43(1): 126044, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31810817

ABSTRACT

Three symbiotic nitrogen-fixing bacteria (BD68T, BD66 and BD73) isolated from root nodules of Lotus tenuis in lowland soils of the Flooding Pampa (Argentina), previously classified as members of the Mesorhizobium genus, were characterized in this study. Phylogenetic analysis of their 16S rRNA gene sequences showed a close relationship to M. japonicum MAFF 303099T, M. erdmanii USDA 3471T, M. carmichaelinearum ICMP 18942T, M. opportunistum WSM 2975T and M. jarvisii ATCC 33699T, with sequence identities of 99.72%-100%. Multilocus sequence analysis of other housekeeping genes revealed that the three isolates belonged to a phylogenetically distinct clade within the genus Mesorhizobium. Strain BD68T was designated as the group representative and its genome was fully sequenced. The average nucleotide identity and in silico DNA-DNA hybridization comparisons between BD68T and the most related type strains showed values below the accepted threshold for species discrimination. Phenotypic and chemotaxonomic features were also studied. Based on these results, BD68T, BD66 and BD73 could be considered to represent a novel species of the genus Mesorhizobium, for which the name Mesorhizobium intechi sp. nov. is hereby proposed. The type strain of this species is BD68T (=CECT 9304T=LMG 30179T).


Subject(s)
Lotus/microbiology , Mesorhizobium/classification , Phylogeny , Root Nodules, Plant/microbiology , Argentina , DNA, Bacterial/genetics , Fatty Acids/analysis , Genes, Bacterial/genetics , Genes, Essential/genetics , Genome, Bacterial/genetics , Mesorhizobium/chemistry , Mesorhizobium/cytology , Mesorhizobium/physiology , Nucleic Acid Hybridization , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Soil Microbiology
3.
Int J Food Microbiol ; 304: 106-118, 2019 Sep 02.
Article in English | MEDLINE | ID: mdl-31176963

ABSTRACT

Nicaraguan cocoa bean fermentations of several single local cocoa varieties originating from the same region (North Highlands of Nicaragua, San Jose de Bocay/El Cuá) were compared to fermentations of blended cocoa varietals from other producing regions of the country (Waslala and Nueva Guinea) making use of High Throughput Sequencing techniques, metabolite target analysis and sensory evaluation of cocoa liquor samples. A succession of the important cocoa-related yeasts Hanseniaspora uvarum/opuntiae, Saccharomyces cerevisiae and/or Pichia kudriavzevii was seen for single varietals and Nueva Guinea fermentations, while Kazachstania humilis dominated the mid and end phase of the Waslala cocoa fermentations. Tatumella species (mainly Tatumella terrea and Tatumella punctata) predominated the bacterial community at the onset of all fermentations followed by unusually late (generally 2 days into the fermentations) appearance of Lactobacillus fermentum relative to fermentations in other parts of the World. Acetobacter spp. were the main acetic acid bacteria during all fermentations, but also Gluconobacter spp. were involved in some single-variety fermentations. All fermentations proved complete as determined by metabolite analysis with bean sucrose being fully depleted and pulp sugars exhausted after 48-72 h of fermentation. From an organoleptic point of view, all Nicaraguan cocoas of this study reflected fine fruity (citrus or berry-like) flavours with distinct herbal or caramel notes. Floral notes were associated with the cases where P. kudriavzevii was involved in the later stages of fermentation. Intense citrus/fruity character was related to high pulp and bean citrate concentrations. Off-notes were found in some over-fermented batches where Bacillus spp. was detected. No relation between cut-test results and organoleptic appreciation was seen.


Subject(s)
Bacteria/metabolism , Cacao/microbiology , Chocolate/microbiology , Fermentation/physiology , Fungi/metabolism , Acetic Acid/metabolism , Acetobacter/metabolism , Bacteria/isolation & purification , Bioreactors/microbiology , Enterobacteriaceae/metabolism , Fungi/isolation & purification , Gluconobacter/metabolism , Hanseniaspora/metabolism , Limosilactobacillus fermentum/metabolism , Pichia/metabolism , Saccharomyces cerevisiae/metabolism
4.
Rev. argent. clín. psicol ; 13(1): 19-33, abr. 2004. tab, graf
Article in Spanish | LILACS | ID: lil-428577

ABSTRACT

El presente trabajo evidencia la eficacia de la terapia comportamental-cognitiva en un amplio rango de trastornos mentales, incluyendo la psicosis. Su crecimiento y difusión se debe a que está enmarcada dentro de las terapias directivas breves por lo que la ecuación costo-eficacia se ve altamente favorecida. La TCC presume que la formación de creencias anómalas genera experiencias psicóticas. Se presenta el modelo ABC que refiere que los delirios de las voces son producto de creencias y no de hechos. El tratamiento que propone consta de una serie de estadios: evaluación, compromiso, establecimiento de objetivos, normalización, formulación, análisis crítico colaborativo, desarrollo de explicaciones alternativas, prevención de recaída, finalización, y por último, la supervisión. Cada uno de ellos incluye problemas potenciales que pueden presentarse. Finalmente se expone un caso clínico a modo ilustrativo del tratamiento descripto


Subject(s)
Cognitive Behavioral Therapy , Psychotic Disorders , Schizophrenia , Delirium , Hallucinations
5.
Rev. argent. clín. psicol ; 13(1): 19-33, abr. 2004. tab, graf
Article in Spanish | BINACIS | ID: bin-255

ABSTRACT

El presente trabajo evidencia la eficacia de la terapia comportamental-cognitiva en un amplio rango de trastornos mentales, incluyendo la psicosis. Su crecimiento y difusión se debe a que está enmarcada dentro de las terapias directivas breves por lo que la ecuación costo-eficacia se ve altamente favorecida. La TCC presume que la formación de creencias anómalas genera experiencias psicóticas. Se presenta el modelo ABC que refiere que los delirios de las voces son producto de creencias y no de hechos. El tratamiento que propone consta de una serie de estadios: evaluación, compromiso, establecimiento de objetivos, normalización, formulación, análisis crítico colaborativo, desarrollo de explicaciones alternativas, prevención de recaída, finalización, y por último, la supervisión. Cada uno de ellos incluye problemas potenciales que pueden presentarse. Finalmente se expone un caso clínico a modo ilustrativo del tratamiento descripto


Subject(s)
Cognitive Behavioral Therapy , Schizophrenia , Psychotic Disorders , Hallucinations , Delirium
SELECTION OF CITATIONS
SEARCH DETAIL