Purification and Characterization of an Ethanol-Tolerant β-Glucosidase from Sporidiobolus pararoseus and Its Potential for Hydrolysis of Wine Aroma Precursors

Abstract

An extracellular ethanol-tolerant β-glucosidase from Sporidiobolus pararoseus was purified to homogeneity and characterized, and its potential use for the enhancement of wine aroma was investigated. The crude enzymatic extract was purified in four steps (concentration, dialysis, ultrafiltration, and chromatography) with a yield of around 40 % for total activity. The purified enzyme (designated Sp-βgl-P) showed a specific activity of approximately 20.0 U/mg, an estimated molecular mass of 63 kDa after sodium dodecyl sulfate polyacrylamide gel electrophoresis, and isoelectric point of 5.0 by isoelectric focusing. Sp-βgl-P has optimal activity at pH 4.0 and at 55 °C. It was stable in a broad pH range at low temperatures and it was tolerant to ethanol and glucose, indicating suitable properties for winemaking. The hydrolysis of glycosidic terpenes was analyzed by adding Sp-βgl-P directly to the wines. The released terpene compounds were evaluated by gas chromatography/mass spectrometry. The enzymatic treatment significantly increased the amount of free terpenes, suggesting that this enzyme could potentially be applicable in wine aroma improvement.

A single desaturase gene from red yeast Sporidiobolus pararoseus is responsible for both four- and five-step dehydrogenation of phytoene

“…pararoseus is a potential candidate organism for the study of the regulation of the carotenoids biosynthetic pathway, due to their production of the primary carotenoid β-carotene and torulene as well as the secondary carotenoids γ-carotene and torularhodin (Mannazzu et al, 2015;Mata-Gomez et al, 2014). However, despite a considerable number of reports on carotenoids bioproduction by S. pararoseus, little is known about the presence of carotenogenic genes, nor the molecular mechanisms underlying carotenoid biosynthesis in S. pararoseus (Baffi et al, 2013;Cabral et al, 2011;Han et al, 2012;Shi et al, 2013).…”

Bg10: A Novel Metagenomics Alcohol-Tolerant and Glucose-Stimulated GH1 ß-Glucosidase Suitable for Lactose-Free Milk Preparation

“…Thus, many researchers have searched for novel enzymes tolerant to glucose or have attempted to learn more about the mechanism that leads to tolerance to implement this feature in other enzymes through engineering [2,26–29]. Moreover, a demand exists for new β-glucosidases with tolerance to some alcohols present in the biofuel and beverage industry processes [12,17,63]. …”

“…This process is largely applied in wine and juice production and involves the liberation of flavouring compounds from certain precursors, such as glycoside monoterpenes (linalool, geraniol, and nerol) [12,17,18]. However, the application of ß-glucosidases could be greatly extended by using many enzyme activities to modify sugars in food products, such as an enzyme’s lactase activity.…”

Optimization of a heat‐tolerant β‐glucosidase production by Bacillus sp. ZJ1308 and its purification and characterization

“…The optimal temperature of the purified β‐glucosidase is 60 °C, which is similar to those of other known ones from some microorganisms, such as Fusarium oxysporum (60 °C) , Aspergillus fumigates (60 °C) , the protoplast fusant of Aspergillus oryzae and A. niger (65 °C) , and Colletotrichum graminicola (65 °C) . Compared to many acidic β‐glucosidases from Sporidiobolus pararoseus (pH 4.0) , A. niger (pH 4.0) , Penicillium aculeatum (pH 4.5) , Oenococcus oeni (pH 5.0–5.5) , and Endophytic fungi (pH 5.0 and 6.0) , the β‐glucosidase from Bacillus sp. ZJ1308 shows an optimal activity at pH 7.0, indicating that it may be neutral.…”

“…Many studies have reported that several β‐glucosidases have a high activity for the hydrolysis of daidzin , genistin , stevioside , oleuropein , and echinacoside . β‐Glucosidase has been widely used for the improvement of wine aroma . Some studies have pointed out that the activity of β‐glucosidase may become a good candidate for the propolis‐freshness index .…”