173 research outputs found

    Assessment of Spontaneous Fermentation and Non-Saccharomyces Sequential Fermentation in Verdicchio Wine at Winery Scale

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    The use of non-Saccharomyces yeasts in sequential fermentation is a suitable biotechnological process to provide specific oenological characteristics and to increase the complexity of wines. In this work, selected strains of Lachancea thermotolerans and Starmerella bombicola were used in sequential fermentations with Saccharomyces cerevisiae and compared with spontaneous and pure S. cerevisiae fermentation trials in Verdicchio grape juice. Torulaspora delbrueckii together with the other two non-Saccharomyces strains (L. thermotolerans, S. bombicola) in multi-sequential fermentations was also evaluated. Wines, obtained under winery vinification conditions, were evaluated for their analytical and sensorial profile. The results indicated that each fermentation gave peculiar analytical and aromatic features of the final wine. L. thermotolerans trials are characterized by an increase of total acidity, higher alcohols and monoterpenes as well as citric and herbal notes. S. bombicola trials showed a general significantly high concentration of phenylethyl acetate and hexyl acetate and a softness sensation while multi-sequential fermentations showed a balanced profile. Spontaneous fermentation was characterized by the production of acetate esters (ethyl acetate and isoamyl acetate), citrus and herbal notes, and tannicity. The overall results indicate that multi-starter fermentations could be a promising tool tailored to the desired features of different Verdicchio wine styles

    Improved Saccharomyces cerevisiae Strain in Pure and Sequential Fermentation with Torulaspora delbrueckii for the Production of Verdicchio Wine with Reduced Sulfites

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    none4The application of yeast strains that are low producers of sulfur compounds is actually required by winemakers for the production of organic wine. This purpose could be satisfied using a native Saccharomyces cerevisiae strain improved for oenological aptitudes. Moreover, to improve the aromatic complexity of wines, sequential fermentations carried out with S. cerevisiae/non-Saccharomyces yeast is widely used. For these reasons, in the present work an improved native S. cerevisiae low producer of sulfite and sulfide compounds was evaluated in pure and in sequential fermentation with a selected Torulaspora delbrueckii. Additionally, the influence of grape juices coming from three different vintages under winery conditions was evaluated. In pure fermentation, improved native S. cerevisiae strain exhibited a behavior related to vintage, highlighting that the composition of grape juice affects the fermentation process. In particular, an increase in ethyl octanoate (vintage 2017) and phenyl ethyl acetate (vintage 2018) was detected. Moreover, isoamyl acetate was highly consistent and could be a distinctive aroma of the strain. The sequential fermentation T. delbrueckii/S. cerevisiae determined an increase in aroma compounds such as phenyl ethyl acetate and ethyl hexanoate. In this way, it was possible to produce Verdicchio wine with reduced sulfites and characterized by a peculiar aromatic tasteopenAgarbati, Alice; Canonico, Laura; Comitini, Francesca; Ciani, MaurizioAgarbati, Alice; Canonico, Laura; Comitini, Francesca; Ciani, Maurizi

    improvement of bioremediation performance for the degradation of petroleum hydrocarbons in contaminated sediments

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    Microcosm bioremediation strategies were applied to sediments contaminated with hydrocarbons. Experiments were performed in aerobic conditions in a single-step treatment and in a two-step anaerobic-aerobic treatment. In aerobic conditions, either inorganic nutrients or composts were added to the microcosms, while, in the first anaerobic phase of the two-step experiment, acetate and/or allochthonous sulfate-reducing bacteria were used. After the treatment under anaerobic conditions, samples were exposed to aerobic conditions in the presence of compost. In the aerobic treatments, 81% hydrocarbon biodegradation was observed after 43 days in the presence of inorganic nutrients. In aerobic conditions in the presence of mature compost, hydrocarbon biodegradation was 51% after 43 days of treatment, whereas it was 47% after 21 days with fresh compost. The two-step experiment allowed us to obtain a hydrocarbon degradation of 91%, after a first anaerobic step with an inoculum of sulfate-reducing prokaryotes

    Lentil Fortification and Non-Conventional Yeasts as Strategy to Enhance Functionality and Aroma Profile of Craft Beer

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    During the last few years, consumer demand has been increasingly oriented to fermented foods with functional properties. This work proposed to use selected non-conventional yeasts (NCY) Lachancea thermotolerans and Kazachstania unispora in pure and mixed fermentation to produce craft beer fortified with hydrolyzed red lentils (HRL). For this, fermentation trials using pils wort (PW) and pils wort added with HRL (PWL) were carried out. HRL in pils wort improved the fermentation kinetics both in mixed and pure fermentations without negatively affecting the main analytical characters. The addition of HRL determined a generalized increase in amino acids concentration in PW. L. thermotolerans and K. unispora affected the amino acid profile of beers (with and without adding HRL). The analysis of by-products and volatile compounds in PW trials revealed a significant increase of some higher alcohols with L. thermotolerans and ethyl butyrate with K. unispora. In PWL, the two NCY showed a different behavior: an increment of ethyl acetate (K. unispora) and beta-phenyl ethanol (L. thermotolerans). Sensory analysis showed that the presence of HRL characterized all beers, increasing the perception of the fruity aroma in both pure and mixed fermentation

    Genetic diversity and variability in two Italian autochthonous donkey genetic types assessed by microsatellite markers

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    Since 13rd century, Italian domestic autochthonous donkey population has been characterised by Mediterranean grey mousy cruciate ancestral phenotype, currently typical of Amiata donkey (AD) genetic type. This phenotype persisted up to the 16th century when a marked introduction of Hispanic and French big sized and dark bay or darkish coloured sires occurred. In the context of a safeguard programme of Latial Equide resources, the aim of this research was to evaluate the genetic diversity and similarity between the AD breed and an autochthonous donkey population native from Lazio, the Viterbese donkey (VD), using molecular markers. A total of 135 animals (50 AD and 85 VD) were genetically characterised by using 16 short tandem repeat markers. A high genetic differentiation between populations (FST=0.158; P<0.01) and a low betweenbreeds genetic similarity (0.233±0.085) were observed. Correspondence analysis, the result of STRUCTURE software analysis and analysis of molecular variance would seem to indicate genetically different entities as well. It would be desirable to increase the number of comparison with other breeds to better understand the origin of VD. Moreover, results obtained in this study suggest that the loss of genetic variation observed in VD could mainly derive from unnoticed sub-population structuring (Wahlund effect), rather than to other factors such as inbreeding, null alleles or selection influence

    Genetic diversity and variability in two Italian autochthonous donkey genetic types assessed by microsatellite markers

    Get PDF
    Since 13rd century, Italian domestic autochthonous donkey population has been characterised by Mediterranean grey mousy cruciate ancestral phenotype, currently typical of Amiata donkey (AD) genetic type. This phenotype persisted up to the 16th century when a marked introduction of Hispanic and French big sized and dark bay or darkish coloured sires occurred. In the context of a safeguard programme of Latial Equide resources, the aim of this research was to evaluate the genetic diversity and similarity between the AD breed and an autochthonous donkey population native from Lazio, the Viterbese donkey (VD), using molecular markers. A total of 135 animals (50 AD and 85 VD) were genetically characterised by using 16 short tandem repeat markers. A high genetic differentiation between populations (FST=0.158; P&lt;.01) and a low between-breeds genetic similarity (0.233±0.085) were observed. Correspondence analysis, the result of STRUCTURE software analysis and analysis of molecular variance would seem to indicate genetically different entities as well. It would be desirable to increase the number of comparison with other breeds to better understand the origin of VD. Moreover, results obtained in this study suggest that the loss of genetic variation observed in VD could mainly derive from unnoticed sub-population structuring (Wahlund effect), rather than to other factors such as inbreeding, null alleles or selection influence

    Sequential fermentation using non-Saccharomyces yeasts for the reduction of alcohol content in wine

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    Over the last few decades there has been a progressive increase in wine ethanol content due to global climate change and modified wine styles that involved viticulture and oenology practices. Among the different approaches and strategies to reduce alcohol content in wine we propose a sequential fermentation using immobilized non-Saccharomyces wine yeasts. Preliminary results showed that sequential fermentations with Hanseniaspora osmophila , Hanseniaspora uvarum , Metschnikowia pulcherrima , Starmerella bombicola and Saccharomyces cerevisiae strains showed an ethanol reduction when compared with pure S. cerevisiae fermentation trials

    Costruire competenze progettuali e valutative attraverso la didattica laboratoriale

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    The achievement of essential skills for teaching professions is a key element in the educational policies of many countries and it also represents an important topic for national and international research in education. Within the framework of Primary Teacher Education degree (University of Bologna), the authors have started a research path focused on laboratory’s teaching effectiveness to promote planning and evaluation skills of future teachers, in a constructivistic perspective. At the moment, we came to the end of the first phase, exploratory and qualitative, that was conducted in a workshop of the second year of the course. Such a phase allowed us to define the ways and tools to investigate teacher expertise in a tutorial. At the same time this outlined the need of integrating experience based strategies with the following practicum, in a longitudinal perspectiveL’acquisizione delle competenze essenziali per la professionalità docente è un elemento centrale nelle politiche educative di molti paesi ed è anche al centro di un interessante filone della ricerca pedagogica nazionale e internazionale. Nell’ambito del Corso di Laurea in Scienze della Formazione Primaria dell’Università di Bologna, si é dato avvio a un percorso di ricerca avente come oggetto esperienze formative laboratoriali e progettate privilegiando una didattica costruttivistica, con l’obiettivo di promuovere la formazione delle competenze di progettazione e valutazione nei futuri insegnanti. Al momento si è giunti al termine di una prima fase, di tipo esplorativo-qualitativo, realizzata all’interno di un laboratorio del secondo anno di corso che, da una parte, ha permesso di definire le modalità e gli strumenti per indagare queste competenze nell’ambito del laboratorio specifico e, dall’altra, ha reso evidente la necessità di articolare tutte le istanze formative di tipo esperienziale e in particolare collegare, in una prospettiva di tipo longitudinale, il laboratorio con il tirocinio curricolare

    Inhibition of microglia overactivation restores neuronal survival in a mouse model of CDKL5 deficiency disorder

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    open9noFunding: This work was supported by the Telethon foundation (grant number GGP19045 to EC), by the Italian parent associations “CDKL5 insieme verso la cura” to EC and by the CARISBO foundation (grant number 2020.0400 to ST).CDKL5 deficiency disorder (CDD), a severe neurodevelopmental disorder characterized by early onset epilepsy, intellectual disability, and autistic features, is caused by mutations in the CDKL5 gene. Evidence in animal models of CDD showed that absence of CDKL5 negatively affects neuronal survival, as well as neuronal maturation and dendritic outgrowth; however, knowledge of the substrates underlying these alterations is still limited. Neuroinflammatory processes are known to contribute to neuronal dysfunction and death. Recent evidence shows a subclinical chronic inflammatory status in plasma from CDD patients. However, to date, it is unknown whether a similar inflammatory status is present in the brain of CDD patients and, if so, whether this plays a causative or exacerbating role in the pathophysiology of CDD.openGalvani, Giuseppe; Mottolese, Nicola; Gennaccaro, Laura; Loi, Manuela; Medici, Giorgio; Tassinari, Marianna; Fuchs, Claudia; Ciani, Elisabetta; Trazzi, StefaniaGalvani, Giuseppe; Mottolese, Nicola; Gennaccaro, Laura; Loi, Manuela; Medici, Giorgio; Tassinari, Marianna; Fuchs, Claudia; Ciani, Elisabetta; Trazzi, Stefani

    Occurrence of Brettanomyces bruxellensis on Grape Berries and in Related Winemaking Cellar

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    The spoilage yeasts belonging to the genus Dekkera (anamorph Brettanomyces) are associated with the fermentation process and can be responsible for off-flavors in wine. Brettanomyces bruxellensis is difficult to isolate from natural environments because of its low diffusion, low presence on the grape surface and low competition capacity, slow growth, and VBNC (viable but not culturable) state, even when selective media are used. In this study, to investigate the origins and occurrence of B. bruxellensis in winemaking, a total of 62 samples from grapes, winery environment, and fermenting musts were taken through direct isolation with a selective medium. B. bruxellensis was not directly detected in the grape samples but was instead widely isolated from the winery environment samples. However, using a combination of enrichment and selective media, eight of fifteen grape samples were positive for B. bruxellensis. Analysis of the genetic traits of the isolates indicated a strict relationship among the strains from the vineyard and the winery. Isolates from the vineyard and the winery were both part of the more common and dominant biotypes suggesting that the vineyard may be the contamination source of B. bruxellensis in the winery environment. For this, grapes may represent the possible primary origin source from which a flow toward the winery environment originates. On the other hand, the wide occurrence of B. bruxellensis in winery indicates that this environment can be considered as the favorable ecological niche for colonization and diffusion of these yeast
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