Pectinolytic yeasts from viticultural and enological environments: novel finding of Filobasidium capsuligenum producing pectinases

MERÍN, M.G.; MENDOZA, L.M.; MORATA DE AMBROSINI, V.I.

JOURNAL OF BASIC MICROBIOLOGY

WILEY-V C H VERLAG GMBH

Lugar: Weinheim; Año: 2014 vol. 54 p. 835 - 842

0233-111X

In this study indigenous yeasts associated with wineries, grapes and Malbec fermented must from San Rafael viticulture region (Argentina) were isolated to select pectinolytic strains for their potential use in enology. Pectinolytic yeasts were identified by physiological and molecular methods. Among 78 isolates, only 9 were able to produce extracellular pectinases. Six isolated from berry surface were identified as Aureobasidium pullulans and the remaining isolates, recovered from wineries, belonged to Saccharomyces cerevisiae and Filobasidium capsuligenum species. Pectinase production was evaluated under vinification-related conditions: pH 3.5, 12 and 28 °C. A. pullulans U-12 produced the highest pectinolytic activity at low temperature (1.16 U mL-1), while F. capsuligenum strains showed good activity at 12 and 28 °C (0.77 and 1.15 U mL-1, respectively) being this study the first report on the capacity of this species to produce pectinases. The pectinolytic activity of F. capsuligenum B-13 showed an optimum at pH 4.5 and two peaks at 20 and 50 ºC. The enzyme half-life was 2 h at 40 ºC and retained 65% of its activity at 40 ºC after 1 h of incubation. This pectinolytic system displayed remarkable activity at pH and temperatures found in vinification, suggesting a potential candidate for applying to wine-making.