background : the aim of this study was to investigate the effect of pulsed ultra-violet (uv) irradiation on inactivation of beer spoilage microorganisms. uv irradiation is nowadays cost effective enough to compete with traditional biological, physical, and chemical treatment technologies and has become an alternative to such methods. material and methods : photoinactivation effects of pulsed uv...

BACKGROUND Saccharomyces cerevisiae var. boulardii is the only yeast species with probiotic properties. It is considered to have therapeutic significance in gastrointestinal disorders. In the present study, a comparative physiological study between this yeast and Saccharomyces cerevisiae (BY4742) was performed by evaluating two prominent traits of probiotic species, responses to different stres...

Saccharomyces uvarum is one species of a genus which has an extensive history of use in the fermentation and food processing industry. S. uvarum, also called S. bayanus, is referred to as a "wine yeast" due to their broad use in the production of wines. Taxonomically, S. uvarum is closely related to Saccharomyces cerevisiae. S. cerevesiae is the used extensively in the baking of bread and the p...

A collection of 33 Saccharomyces yeasts were used for wine fermentation with a sole nitrogen source: ammonium and four individual aroma-inducing amino acids. The performance chemical composition evaluated. most valuable sources valine as promoter on non-cerevisiae strains, phenylalanine fruity aromas enhancer whereas the ethanol yield was lessened by leucine isoleucine. S. cerevisiae SC03 kudri...

BACKGROUND The production of ethanol and other fuels and chemicals from lignocellulosic materials is dependent of efficient xylose conversion. Xylose fermentation capacity in yeasts is usually linked to xylose reductase (XR) accepting NADH as cofactor. The XR from Scheffersomyces stipitis, which is able to use NADH as cofactor but still prefers NADPH, has been used to generate recombinant xylos...

Background High temperature inhibits cell growth and ethanol fermentation of Saccharomyces cerevisiae. As a complex phenotype, thermotolerance usually involves synergistic actions of many genes, thereby being difficult to engineer. The overexpression of either endogenous or exogenous stress-related transcription factor genes in yeasts was found to be able to improve relevant stress tolerance of...

Hanseniaspora guilliermondii and Hanseniaspora uvarum were tested in grape must fermentations as pure and mixed starter cultures with Saccharomyces cerevisiae. In pure cultures, the specific growth rates found were 0.29 h(-1) for H. uvarum, 0.23 h(-1) for H. guilliermondii and 0.18 h(-1) for S. cerevisiae. No significant differences were observed between these values and those obtained in mixed...

Pyruvate carboxylase is the sole anaplerotic enzyme in glucose-grown cultures of wild-type Saccharomyces cerevisiae. Pyruvate carboxylase-negative (Pyc(-)) S. cerevisiae strains cannot grow on glucose unless media are supplemented with C(4) compounds, such as aspartic acid. In several succinate-producing prokaryotes, phosphoenolpyruvate carboxykinase (PEPCK) fulfills this anaplerotic role. Howe...

Yeast Saccharomyces cerevisiae is one of the simplest eukaryotic model organisms to study various parameters ethanol tolerance and has attracted a huge consideration for cost-conscious production bioethanol by fermentation soluble sugars. Ethanol crucial efficient from S. cerevisiae. In this study, we examined role HAL5 protein kinase in comparing cell growth, survival, stress responses wild-ty...