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3. Todaro A., Palmeri R., Barbagallo R.N., Pifferi P.G., Spagna G. (2007). Increase of Trans-Resveratrol in wine with pure β-glucosidase. Food Chemistry, 107(4), 1570-1575.The resveratrol is a phenolic compound, which belongs to the family of the stilbenes. This compound is alsopresent in a number of vegetable families, including the Vitaceae and, within these ones, also in the Vitisvinifera. In wines, the trans-resveratrol seems to derive, at least in certain measure, from the endogenous β-glucosidase activity of grape, yeasts and bacteria (malolactic fermentation).Nevertheless, the β-glucosidase activity is inhibited by the sugar present in must, whereas the activity which isexpressed by those yeasts commonly used in oenology, is weak and insufficient. This happens because thisactivity is inhibited by the ethanol developed during the fermentation process.In this way, in the wine making process, we only achieve partial retention of polydatin in trans-resveratrol. Inthis research, it was used the β-glucosidase obtained from a commercial enzymatic preparation accuratelypurified by other side activities and yeast, which is normally used in oenology, in order to increase theresveratrol quantity in wines.This process will be achieved by hydrolyzing glucosides resveratrol, without interfering with the product’ssensory characteristics and increasing its health and nutritional properties. An increase of about 75% wasreached through commercial enzymatic preparations, without interfering with the physico-chemicalcharacteristics of wines. On the contrary, the Saccharomyces stock increased its way in free phenols, although itacted negatively towards the wine colour, because of its anthocyanasic activity.4. Spagna G., Barbagallo R.N. and Palmeri R. (2008). Enzymes in beverage Technology. RecentResearch Developments in Food Biotechnology. Enzymes as Additives or Processing Aids,85-110. Editors: Raffaele Porta, Prospero Di Pierro and Loredana Mariniello.The main drawbacks of the enzymes associated with production and storage of beverage have been studied tohighlight remedial strategies. The enzymes considered were endogenous to vegetables, and exogenous from thecommercial preparations most commonly used in the beverage technology5. Quatrini P., Marineo S., Puglia A.M., Restuccia C., Caggia C., Randazzo C., Spagna G.,Barbagallo R.N., Palmeri R., Giudici P. (2008). Partial sequencing of the β-glucosidaseencodinggene from yeast strains isolated from musts and wines. 2008. Annals ofMicrobiology, 58: 3.The aim of the present work was the identification of the gene encoding for β-glucosidase and its partial sequencingin the strains Pichia anomala AL112, Hanseniaspora uvarum Y8 and Saccharomyces cerevisiaeAL41. To this aim degenerated primers, designed on the basis of aminoacid similarities of four known yeast β-glucosidases, have been used in PCR amplifications. An expected fragment of about 200 bp was amplified fromall the DNAs, cloned and sequenced. Sequence homology demonstrated for the first time the presence of a β-glucosidase encoding gene in Hanseniaspora uvarum and Saccharomyces cerevisiae.SISTAL - SOCIETA’ ITALIANA DI SCIENZE E TECNOLOGIE ALIMENTARIDipartimento di Scienze e Tecnologie Agroalimentari, Università degli Studi della TusciaVia San Camillo de Lellis, 01100 ViterboTel.: 0761- 35 74 94/7 , Fax: 0761- 35 74 98, e-mail: mmoresi@unitus.it92