Search results for " yeast"
showing 10 items of 152 documents
Food-grade argan oil supplementation in molasses enhances fermentative performance and antioxidant defenses of active dry wine yeast
2015
The tolerance of the yeast Saccharomyces cerevisiae to desiccation is important for the use of this microorganism in the wine industry, since active dry yeast (ADY) is routinely used as starter for must fermentations. Both biomass propagation and dehydration cause cellular oxidative stress, therefore negatively affecting yeast performance. Protective treatments against oxidative damage, such as natural antioxidants, may have important biotechnological implications. In this study we analysed the antioxidant capacity of pure chemical compounds (quercetin, ascorbic acid, caffeic acid, oleic acid, and glutathione) added to molasses during biomass propagation, and we determine several oxidative …
Oral yeast colonization throughout pregnancy
2017
Background Recent studies suggest that placenta may harbour a unique microbiome that may have origin in maternal oral microbiome. Although the major physiological and hormonal adjustments observed in pregnant women lead to biochemical and microbiological modifications of the oral environment, very few studies evaluated the changes suffered by the oral microbiota throughout pregnancy. So, the aim of our study was to evaluate oral yeast colonization throughout pregnancy and to compare it with non-pregnant women. Material and Methods The oral yeast colonization was assessed in saliva of 30 pregnant and non-pregnant women longitudinally over a 6-months period. Demographic information was collec…
Postmarketing nutrivigilance safety profile: a line of dietary food supplements containing red yeast rice for dyslipidemia
2021
IntroductionIn the absence of a European standardized postmarketing food supplement surveillance system (nutrivigilance), some member states and companies have developed their own approaches to monitoring potential adverse reactions to secure a high level of product safety. This paper describes the use of a nutrivigilance system in monitoring the incidence of spontaneously reported suspected adverse reactions associated with food supplements containing red yeast rice (RYR).Material and methodsWe report the data from a widely used product marketed under the trademark Armolipid/Armolipid Plus. Postmarketing information was collected in a voluntary nutrivigilance system established by the manu…
Tor-Sch9 deficiency activates catabolism of the ketone body-like acetic acid to promote trehalose accumulation and longevity
2014
In mammals, extended periods of fasting leads to the accumulation of blood ketone bodies including acetoacetate. Here we show that similar to the conversion of leucine to acetoacetate in fasting mammals, starvation conditions induced ketone body-like acetic acid generation from leucine in S. cerevisiae. Whereas wild-type and ras2Δ cells accumulated acetic acid, long-lived tor1Δ and sch9Δ mutants rapidly depleted it through a mitochondrial acetate CoA transferase-dependent mechanism, which was essential for lifespan extension. The sch9Δ-dependent utilization of acetic acid also required coenzyme Q biosynthetic genes and promoted the accumulation of intracellular trehalose. These results indi…
In vitro Antifungal Activity of Biopolymeric Foam Activated with Carvacrol
2020
Background: Active packaging represents a defining strategy to improve food quality and safety of the packaged foods. This study aimed to evaluate the in vitro ability of commercial biopolymeric foams, namely Mater-Bi (MB), activated with 20% of carvacrol, to develop a completely biodegradable and compostable packaging to inhibit the growth of spoilage and pathogenic yeasts.
 Methods: MB foams, with and without carvacrol, were produced by melt mixing and the foaming process was performed in a laboratory press. The antifungal activity of foams containing carvacrol was tested applying the disk diffusion method. Statistical analysis was done using XLStat software version 7.5.2 for Excel.&…
Evaluation of yeasts from Ecuadorian chicha by their performance as starters for alcoholic fermentations in the food industry
2020
Yeasts involved in the spontaneous fermentation of traditional beverages like chicha (indigenous Andean beer) may have the potential to be used as starter cultures to improve the quality and microbiological safety of these products, but also as non-conventional alternatives to other food alcoholic fermentations. In this research, we isolated, identified and characterised yeast strains from four Ecuadorian chichas made by using four different raw materials: rice (RC), oat (OC), grape (GC) and a mixture of seven corn varieties (yamor, YC). Finally, 254 yeast isolates were obtained and identified by molecular methods. Eleven yeast genera and 16 yeast species were identified with relatively few…
Saccharomyces eubayanusandSaccharomyces uvarumassociated with the fermentation ofAraucaria araucanaseeds in Patagonia
2014
Mudai is a traditional fermented beverage, made from the seeds of the Araucaria araucana tree by Mapuche communities. The main goal of the present study was to identify and characterize the yeast microbiota responsible of Mudai fermentation as well as from A. araucana seeds and bark from different locations in Northern Patagonia. Only Hanseniaspora uvarum and a commercial bakery strain of Saccharomyces cerevisiae were isolated from Mudai and all Saccharomyces isolates recovered from A. araucana seed and bark samples belonged to the cryotolerant species Saccharomyces eubayanus and Saccharomyces uvarum. These two species were already reported in Nothofagus trees from Patagonia; however, this …
Evolution of microbiological and chemical parameters during red wine making with extended post-fermentation maceration.
2014
Abstract The aim of the present work was to investigate the microbiological, chemical, and sensory characteristics of red wine subjected to post-fermentation maceration that was extended to 90 days. For this purpose, the ‘Aglianico di Taurasi’ grape was used as a case study. The total yeast concentration increased until day 40 of maceration and decreased thereafter, whereas the concentration of lactic acid bacteria slightly increased. Dekkera/Brettanomyces spp. and acetic acid bacteria were not detected. The yeast community was composed of Saccharomyces cerevisiae, Zygosaccharomyces bisporus, Metschnikowia pulcherrima, Hanseniaspora guilliermondii, Hanseniaspora uvarum, Pichia guilliermondi…
Yeasts vectored by migratory birds collected in the Mediterranean island of Ustica and description of Phaffomyces usticensis f.a. sp. nov., a new spe…
2014
Nine yeast species belonging to genera Candida , Cryptococcus , Phaffomyces , Rhodotorula and Wickerhamomyces , and one species of Aureobasidium genus were isolated from the cloaca of migratory birds. Candida glabrata and C. inconspicua were the species most frequently isolated and Wickerhamomyces sylviae , which has recently been described as a new species isolated from bird cloaca, was again found. The majority of isolates showed the ability to grow up to 40 °C and/or at pH 3.0, two environmental conditions typical of the digestive tract of birds. The phylogenetic analysis of the D1/D2 domain of 26S rRNA gene placed the cultures of Phaffomyces in a new lineage that differed from the close…