RESUMEN
Bacterial and fungal community dynamics during microbially-enhanced composting of olive mill solid waste (wet husk), used as a sole raw material, were analysed in a process carried out at industrial pilot and at farm level by the PCR-DGGE profiling of the 16 and 26S rRNA genes. The use of microbial starters enhanced the biotransformation process leading to an earlier and increased level of bacterial diversity. The bacterial community showed a change within 15 days during the first phases of composting. Without microbial starters bacterial biodiversity increased within 60 days. Moreover, the thermophilic phase was characterized by the highest bacterial biodiversity. By contrast, the biodiversity of fungal communities in the piles composted with the starters decreased during the thermophilic phase. The biodiversity of the microbial populations, along with physico-chemical traits, evolved similarly at industrial pilot and farm level, showing different maturation times.
Asunto(s)
Agricultura , Bacterias/metabolismo , Hongos/metabolismo , Residuos Industriales/análisis , Olea/química , Suelo/química , Residuos Sólidos/análisis , Bacterias/genética , Biodegradación Ambiental , Biodiversidad , Análisis por Conglomerados , Electroforesis en Gel de Gradiente Desnaturalizante , Hongos/genética , Filogenia , Proyectos Piloto , TemperaturaRESUMEN
The production of a compost from olive wet husks is described. The process is enhanced through the use of starters prepared with virgin husks enriched with selected microbial cultures. This approach, with respect to composting without the use of starters, allows to achieve faster start of the process (10 vs. 45 days), deeper humification (humification rate 19.2 vs. 12.2), shorter maturation time (2 vs. 4-5 months) and better detoxification of the starting material. Furthermore, the compost produced can effectively substitute for turf as a cultivation substrate in horticulture at greenhouse level, with beneficial effects on nutraceutical traits of tomato fruits.
Asunto(s)
Olea/química , Olea/microbiología , Componentes Aéreos de las Plantas/química , Componentes Aéreos de las Plantas/microbiología , Microbiología del Suelo , Suelo/química , Solanum lycopersicum/microbiología , HumectabilidadRESUMEN
Eighty four isolates of Brettanomyces bruxellensis, were collected during fermentation of Sangiovese grapes in several Tuscan wineries and characterized by restriction analysis of 5.8S-ITS and species-specific PCR. The isolates were subsequently analysed, at strain level, by the combined use of the RAPD-PCR assay with primer OPA-02 and the mtDNA restriction analysis with the HinfI endonuclease. This approach showed a high degree of polymorphism and allowed to identify seven haplotypes, one of them being the most represented and widely distributed (72 isolates, 85.7%). Physiological traits of the yeasts were investigated under a wine model condition. Haplotypes clustered into two groups according to their growth rates and kinetics of production of 4-ethylphenol and 4-ethylguaiacol. Hexylamine was the biogenic amine most produced (up to 3.92 mg l(-1)), followed by putrescine and phenylethylamine. Formation of octapamine was detected by some haplotypes, for the first time.
Asunto(s)
Brettanomyces/genética , Brettanomyces/fisiología , Vino/clasificación , Vino/microbiología , ADN de Hongos/genética , ADN de Hongos/aislamiento & purificación , ADN Intergénico , Variación Genética , Italia , Reacción en Cadena de la Polimerasa/métodos , Especificidad de la EspecieRESUMEN
AIMS: Characterize from both genetic and phenotypic standpoints the indigenous strains of Saccharomyces spp. associated with natural fermentation of 'Malvasia delle Lipari'. METHODS AND RESULTS: A total of 192 yeast isolates were obtained from completed fermentation of a mix of 'Malvasia delle Lipari' (92%) and 'Corinto nero' (8%) grapes in two wineries in Salina Island (Sicily, Italy). Fifty-one Saccharomyces spp. isolates were characterized using ITS-PCR, random amplified polymorphic DNA-PCR and mitochondrial DNA restriction fragment length polymorphism and 12 biotypes were identified. Representative strains of each biotype, tested for their physiological traits, exhibit different killer activity, fermentation vigour, production of hydrogen sulphide and show similar beta-glucosidase and proteolytic activity. CONCLUSIONS: It is possible to cluster in different groups naturally occurring indigenous biotypes of Saccharomyces cerevisiae from 'Malvasia delle Lipari' on the basis of molecular profiles. SIGNIFICANCE AND IMPACT OF THE STUDY: Deeper insight on indigenous wine yeast of a conserved environment. The knowledge gained might offer a contribution to the selection of autochthonous wine yeast as starters for controlled fermentations.
Asunto(s)
Biodiversidad , Saccharomyces/clasificación , Saccharomyces/aislamiento & purificación , Vitis/microbiología , ADN de Hongos/genética , ADN Mitocondrial/genética , ADN Espaciador Ribosómico/genética , Fermentación , Genes del Tipo Sexual de los Hongos , Genotipo , Sulfuro de Hidrógeno/metabolismo , Técnicas de Tipificación Micológica , Péptido Hidrolasas/metabolismo , Reacción en Cadena de la Polimerasa/métodos , Polimorfismo de Longitud del Fragmento de Restricción , Técnica del ADN Polimorfo Amplificado Aleatorio/métodos , Saccharomyces/genética , Saccharomyces/fisiología , Sicilia , beta-Glucosidasa/metabolismoRESUMEN
BACKGROUND: This study aimed to verify whether the assessment of defect severity and the infusion of nitrates during tracer injection improve the capability of data-based 99mTc-labeled sestamibi single-photon emission computed tomography (SPECT) to recognize hibernating myocardium. METHODS AND RESULTS: Of 66 asynergic coronary territories in 40 patients with left ventricular dysfunction, 28 had postrevascularization functional recovery (hibernating) and 38 had unchanged dysfunction (fibrotic). Defect severity was lower in the hibernating than in the fibrotic territories on both baseline (p < 0.01) and nitrate SPECT (p < 0.002). Nitrate was superior to baseline SPECT to differentiate the hibernating from the fibrotic territories (sensitivity 96% vs 75%, p < 0.05; receiver-operating characteristic curve area 0.75 vs 0.63, p < 0.001) and to identify the patients with improved left ventricular ejection fraction (receiver-operating characteristic curve area 0.68 vs 0.58; p < 0.05). CONCLUSIONS: The analysis of defect severity in combination with nitrate infusion clearly improves the value of 99mTc-labeled sestamibi SPECT for the recognition of hibernating myocardium and the prediction of postrevascularization recovery.