College of Enology , Northwest A&F University , Yangling 712100 , Shaanxi , People's Republic of China.
J Agric Food Chem. 2019 May 8;67(18):5169-5176. doi: 10.1021/acs.jafc.9b00863. Epub 2019 Apr 25.
The aim of this study was to evaluate the potential application of cell-surface-displayed β-glucosidase (BGL) in wine aroma enhancement. Gene cassettes for the surface display of Aspergillus niger BGL were constructed using different promoters ( GPD and SED1) and glycosylphosphatidylinositol (GPI) anchoring regions (Sag1, Sed1, and Cwp2). The differences in surface-display cassettes, the tolerance of the displayed BGL to typical winemaking conditions, and the hydrolysis capacity for the liberation of grape aroma glycosides were analyzed. Results revealed that simultaneous utilization of GPD promoter and Sed1 anchoring domain achieved the highest BGL activity. The displayed BGL exhibited relatively high activity at pH 3.0 and at glucose concentration below 2.5% (w/v), compared to commercial enzyme (AR 2000), but exhibited no significant difference under varying ethanol concentrations. Furthermore, the surface-displayed BGL presented better ability to release free terpenols compared to AR 2000. Therefore, a surface-display system could provide a new viable solution for enhancing wine aroma.
本研究旨在评估细胞表面展示β-葡萄糖苷酶（BGL）在葡萄酒香气增强中的潜在应用。使用不同的启动子（GPD 和 SED1）和糖基磷脂酰肌醇（GPI）锚定区（Sag1、Sed1 和 Cwp2）构建了用于曲霉黑曲霉 BGL 表面展示的基因盒。分析了表面展示盒的差异、展示 BGL 对典型酿酒条件的耐受性以及释放葡萄香气糖苷的水解能力。结果表明，同时利用 GPD 启动子和 Sed1 锚定结构域可实现最高的 BGL 活性。与商业酶（AR 2000）相比，展示的 BGL 在 pH 3.0 和葡萄糖浓度低于 2.5%（w/v）时表现出相对较高的活性，但在不同乙醇浓度下没有显著差异。此外，表面展示的 BGL 释放游离萜烯醇的能力优于 AR 2000。因此，表面展示系统可为增强葡萄酒香气提供一种新的可行解决方案。
