title: Beta-glucosidase from the grape native yeast Debaryomyces vanrijiae: purification, characterization, and its effect on monoterpene content of a Muscat grape juice.
abstract: Six hundred ten yeast colonies isolated from various vineyards in Chile were screened for the presence of a beta-glucosidase activity as well as the resistance to glucose and ethanol inhibition. Among them, Debaryomyces vanrijiae was found to produce high levels of an extracelular beta-glucosidase which was tolerant to glucose (K(i) = 439 mM) and ethanol inhibitions. The enzyme (designated DV-BG) was purified to apparent homogeneity, respectively, by gel filtration, ion-exchange, and chromatofocusing techniques. Its molecular weight was 100 000, and its pI 3.0, optimum pH, and temperature activities were 5.0 and 40 degrees C, respectively, and had a V(max) of 47.6 micromol min(-)(1) mg(-)(1) and a K(m) of 1.07 mM. The enzyme was active against different beta-d-glucosides including glucosidic flavor precursors. The disaccharidic flavor precursors were not substrates for the enzyme. When added to a Muscat grape juice, the concentration of several monoterpenes increased as the consequence of its hydrolytic activity.
authors.affiliation: Departamento de Ingeniería Química y Bioprocesos, Pontificia Universidad Católica de Chile, P.O. Box 306 correo 22, Santiago, Chile.
authors.forename: Andrea
authors.initials: A
authors.lastname: Belancic
authors.forename: Ziya
authors.initials: Z
authors.lastname: Gunata
authors.forename: Marie-Jose
authors.initials: MJ
authors.lastname: Vallier
authors.forename: Eduardo
authors.initials: E
authors.lastname: Agosin
mesh_terms: D001203:Ascomycota / Q000201:enzymology*; D001628:Beverages / Q000032:analysis*; D002845:Chromatography; D005638:Fruit / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007700:Kinetics; D008970:Molecular Weight; D039821:Monoterpenes / Q000032:analysis* / Q000378:metabolism; D013379:Substrate Specificity; D013696:Temperature; D027843:Vitis / Q000737:chemistry*; D001617:beta-Glucosidase / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism*
chemical_list: D039821:Monoterpenes; D001617:beta-Glucosidase