Study of morphological, physiological and genetic properties of newly isolation and select second level yeast strains from the area Tikvesh, Macedonia

We studied 10 strains of yeast from 80 newly selected strain to identify the genera and species belonging. Was made morphological and cultural characteristic, the study was sporulation, fermentation and assimilation of sugars and other carbon sources. Seven of the ten selected second level strains defined clonal diversity by PCR method to identify within the species Saccharomyces cerevisiae.Five of the cultures present in the different strains within a species

Study newly yeast strains for wine production from the area of Demir Kapija, Macedonia

We studied 10 strains of yeast from 80 newly selected strains for their application in producing regional red wines in the region of Demir Kapija, Macedonia. Made by experienced wine varieties Cabernet Sauvignon and Vranets whose composition and organoleptic profile correspond to the quality of young red wines from these varieties. As the most suitable for the production of varietal wines Vranets indicated strains F-78 and F-8, but Cabernet Sauvignon F-78 and F-70. Guilt is established in a typical aroma, intense fruity notes, dense structures and harmonic taste. Were prepared Spider - charts for the best options Keywords: yeast selection, regional wines, Vranets, Cabernet Sauvignon, organoleptic profil

Partial vinylphenol reductase purification and characterization from Brettanomyces bruxellensis

International audienceBrettanomyces is the major microbial cause for wine spoilage worldwide and causes significant economic losses. The reasons are the production of ethylphenols that lead to an unpleasant taint described as 'phenolic odour'. Despite its economic importance, Brettanomyces has remained poorly studied at the metabolic level. The origin of the ethylphenol results from the conversion of vinylphenols in ethylphenol by Brettanomyces hydroxycinnamate decarboxylase. However, no information is available on the vinylphenol reductase responsible for the conversion of vinylphenols in ethylphenols. In this study, a vinylphenol reductase was partially purified from Brettanomyces bruxellensis that was active towards 4-vinylguaiacol and 4-vinylphenol only among the substrates tested. First, a vinylphenol reductase activity assay was designed that allowed us to show that the enzyme was NADH dependent. The vinylphenol reductase was purified 152-fold with a recovery yield of 1.77%. The apparent K(m) and V(max) values for the hydrolysis of 4-vinylguaiacol were, respectively, 0.14 mM and 1900 U mg(-1). The optimal pH and temperature for vinylphenol reductase were pH 5-6 and 30 degrees C, respectively. The molecular weight of the enzyme was 26 kDa. Trypsic digest of the protein was performed and the peptides were sequenced, which allowed us to identify in Brettanomyces genome an ORF coding for a 210 amino acid protein