Use of fortified pied de cuve as an innovative method to start spontaneous alcoholic fermentation for red winemaking

Background and Aims: Some wineries, in order to promote the growth of yeasts able to ferment grape musts, traditionally produce wines using the ‘pied de cuve’ method. The aim of the present work was to study the performance of fortified pied de cuve (FPdC) prepared by addition of wine. Method and Results: Two FPdCs were prepared with the addition of wine at 1.5 and 3% (v/v) of ethanol to the musts and allowed to spontaneously ferment. The FPdCs were then added to fresh bulk musts in order to accelerate the spontaneous alcoholic fermentation (AF). Interestingly, several Saccharomyces cerevisiae strains isolated during the pied de cuve preparation were detected at the highest concentration throughout AF. The chemical composition of the wines conformed to commercial regulations. The volatile organic compounds (VOCs) were mainly represented by diethyl succinate and ethyl lactate, as well as by hexanol and isoamyl alcohol. Principal component analysis of the chemical parameters, VOCs and sensory data showed that the use of experimental pied de cuve influenced positively the composition of the final wines. Conclusion: The FPdC had no negative impact on the microbiological and chemical composition of wines, but it affected the diversity of the species S. cerevisiae present during AF and the sensory profile of the final wine. Significance of the Study: This study provided evidence that FPdC accelerates spontaneous AF and influences the sensory profile of red wines

The prodromes of Parkinson's disease.

"This is the peer reviewed version of the following article: Rees RN, Noyce AJ, Schrag A. The prodromes of Parkinson's disease. Eur J Neurosci. 2018;00:1–8. https://doi.org/10.1111/ejn.14269, which has been published in final form at https://doi.org/10.1111/ejn.14269. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions."Whilst the diagnosis of Parkinson’s disease (PD) relies on the motor triad of bradyki-nesia, rigidity and tremor, the underlying pathological process starts many years be-fore these signs are overt. In this prodromal phase of PD, a diverse range of non- motor and motor features can occur. Individually they do not allow a diagnosis of PD, but when considered together, they reflect the gradual development of the clinical syn-drome. Different subgroups within the prodromal phase may exist and reflect different underlying pathology. Here, we summarise the evidence on the prodromal phase of PD in patient groups at increased risk of PD with well described prodromal features: patients with idiopathic rapid eye movement sleep behaviour disorder, patients with idiopathic anosmia and families with monogenic mutations that are closely linked to PD pathology. In addition, we discuss the information on prodromal features from ongoing studies aimed at detecting prodromal PD in the general population. It is likely that better delineation of the clinical prodromes of PD and their progression in these high- risk groups will improve understanding of the underlying pathophysiology.Parkinson’s UK, Grant/Award Number: G1606; Barts Charity (Preventive Neurology Grant); National Institute for Health Research University College London Hospitals Biomedical Research Centr

Effect of the mechanical harvest of drupes on the quality characteristics of green fermented table olives

Background: Because of damage caused by mechanical harvesting, the drupes for table olive production are traditionally hand harvested. Until now, no data have been available on the microbiological and chemical features of mechanically harvested drupes during fermentation. Results: Drupes mechanically harvested and inoculated with Lactobacillus pentosus OM13 were characterized by the lowest concentrations of potential spoilage microorganisms. On the other hand, drupes mechanically harvested and subjected to spontaneous fermentation showed the highest concentration of Enterobacteriaceae and pseudomonads during transformation. The lowest decrease of pH (4.20) was registered for the trials inoculated with the starter culture. Differences in terms of volatile organic compounds were estimated among trials. Multivariate analysis showed that the olives processed from the drupes mechanically harvested and inoculated with starter were closely related to control production (drupes manually harvested) in terms of microbiological and pH values. Sensory analysis evidenced negative evaluations only for the uninoculated trials. Conclusion: Drupes mechanically harvested and subjected to a driven fermentation with Lactobacillus pentosus OM13 determined the production of table olives with appreciable organoleptic features. Thus mechanical harvesting performed using a trunk shaker equipped with an inverse umbrella and the addition of starter lactic acid bacteria represents a valuable alternative to manual harvesting for table olive production at the industrial level

Optimization of a rapid method for studying the cellular location of β-glucosidase activity in wine yeasts

Aims: To improve a method for determining β-glucosidase activity and to apply it in yeasts isolated from wine ecosystems from 'La Mancha' region and to know its cellular location. Methods and Results: A total of 82 wine yeasts were identified (PCR/RFLP) and evaluated for their β-glucosidase activity. First, they were qualitatively evaluated by growth on YNB cellobiose, the activity was quantified using different culture media, under aerobic and anaerobic conditions and cells after 24-72 h of growth. To study the location activity, five fractions were obtained (supernatant, whole cell, cell wall, cytosol and cell membrane). The enzymatic assays were optimized, being: growth in YP cellobiose for 72 h in aeration conditions and, after cell removing, enzyme analysis with 128 g 1-1 of cellobiose as substrate, for 30 min at 30°C. The genus that displayed the greatest activity were Pichia, Hanseniaspora and Rhodotorula, and the activity was intracellular. Conclusions: The study showed that β-glucosidase activity was induced by the carbon source and was aerobic dependent. The non-Saccharomyces species displayed the greatest activity, which was intracellular and strain-dependent. Significance and Impact of the Study: This study developed a reliable method for screening β-glucosidase activity in yeasts isolated from wine ecosystems. This activity is very important in the release of monoterpenols from glycoside precursors for the enhancement of wine aromas. © 2005 The Society for Applied Microbiology.Articl

Evaluation of polygalacturonase activity in Saccharomyces cerevisiae wine strains

AgriwetenskappeInstituut Vir WynbiotegnologiePlease help us populate SUNScholar with the post print version of this article. It can be e-mailed to: [email protected]

Yeast biodiversity from oleic ecosystems: Study of their biotechnological properties

The aim of this study was to know the yeast biodiversity from fresh olive (Olea europaea L.) fruits, olive paste (crush olives) and olive pomace (solid waste) from Arbequina and Cornicabra varieties. Yeasts were isolated from fruits randomly harvested at various olive groves in the region of Castilla La Mancha (Spain). Olive paste and pomace, a byproduct of the processing of this raw material, were also collected in sterile flasks from different oil mills. Molecular identification methodology used included comparison of polymerase chain reaction (PCR) amplicons of their 5.8S rRNA gene and internal transcribed spacers ITS1 and ITS2 followed by restriction pattern analysis (RFLP). For some species, sequence analysis of the 5.8S rDNA gene was necessary. The results were compared to sequences held in public databases (BLAST). These techniques allowed to identify fourteen different species of yeasts, belonging to seven different genera (Zygosaccharomyces, Pichia, Lachancea, Kluyveromyces, Saccharomyces, Candida, Torulaspora) from the 108 yeast isolates. Species diversity was thus considerable: Pichia caribbica, Zygosaccharomyces fermentati (Lachancea fermentati) and Pichia holstii (Nakazawaea holstii) were the most commonly isolated species, followed by Pichia mississippiensis, Lachancea sp., Kluyveromyces thermotolerans and Saccharomyces rosinii. The biotechnological properties of these isolates, was also studied. For this purpose, the activity of various enzymes (beta-glucosidase, beta-glucanase, carboxymethylcellulase, polygalacturonase, peroxidase and lipase) was evaluated. It was important that none of species showed lipase activity, a few had cellulase and polygalacturonase activities and the majority of them presented beta-glucanase, beta-glucosidase and peroxidase activities. (C) 2010 Elsevier Ltd. All rights reserved

Characterization of the B-glucosidases activity produced by enological strains of non-<I>Saccharomyces </I>yeast.

AgriwetenskappeInstituut Vir WynbiotegnologiePlease help us populate SUNScholar with the post print version of this article. It can be e-mailed to: [email protected]