An efficient b-glucosidase (bG)-producing strain, Wickerhamomyces anomalus BS81, was isolated from naturally fermented olive brine and identified based on PCR/restriction fragment length polymorphism of the rDNA internal transcribed spacer and sequence analysis of the D1/D2 region of the 26S rRNA gene. The hydrolytic activity of the bG had an optimum pH of 8.5 and an optimum temperature of 35 1C. The enzyme had high substrate specificity and high catalytic efficiency (Km 0.99mM, Vmax 14Ug1 of cells) for p-nitrophenyl-b-D-glucopyranoside. The enzyme was activated by increasing concentrations of NaCl, with maximum activity at 150 g L1 NaCl. Although bGs have been purified and characterized from several other sources, the W. anomalus bG is unique among bGs because its relative maximum activity occurs at alkaline pH and 35 1C. Moreover, the yeast strain has esterase activity that acts synergistically with bG to degrade oleuropein to debitter table olives and olive oil.
|Titolo:||An alkaline beta-glucosidase isolated from an olive brine strain of Wickerhamomyces anomalus|
|Data di pubblicazione:||2011|
|Appare nelle tipologie:||1.1 Articolo in rivista|