An alkaline beta-glucosidase isolated from an olive brine strain of Wickerhamomyces anomalus

作者：Restuccia Cristina^*; Muccilli Serena; Palmeri Rosa; Randazzo Cinzia L; Caggia Cinzia; Spagna Giovanni

来源：FEMS Yeast Research, 2011, 11(6): 487-493.

DOI：10.1111/j.1567-1364.2011.00738.x

• naturally fermented olives
• biological debittering
• Wickerhamomyces anomalus
• beta-glucosidase
• esterase
• biochemical properties

An efficient beta-glucosidase (beta G)-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 beta G had an optimum pH of 8.5 and an optimum temperature of 35 degrees C. The enzyme had high substrate specificity and high catalytic efficiency (K(m) 0.99mM, V(max) 14Ug(-1) of cells) for p-nitrophenyl-beta-D-glucopyranoside. The enzyme was activated by increasing concentrations of NaCl, with maximum activity at 150 g L(-1) NaCl. Although beta Gs have been purified and characterized from several other sources, the W. anomalus beta G is unique among beta Gs because its relative maximum activity occurs at alkaline pH and 35 degrees C. Moreover, the yeast strain has esterase activity that acts synergistically with beta G to degrade oleuropein to debitter table olives and olive oil.

• 出版日期2011-9