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The aim of this work was to rapidly screen indigenous yeasts with high levels of β-glucosidase activity and assess the potential of glycosidase extracts for aroma enhancement in winemaking. A semiquantitative colorimetric assay was applied using 96-well plates to screen yeasts from 3 different regions of China. Isolates with high β-glucosidase activity were confirmed by the commonly used pNP assay. Among 493 non-Saccharomyces isolates belonging to 8 generas, 3 isolates were selected for their high levels of β-glucosidase activity and were identified as Hanseniaspora uvarum, Pichia membranifaciens, and Rhodotorula mucilaginosa by sequence analysis of the 26S rDNA D1/D2 domain. β-Glucosidase in the glycosidase extract from H. uvarum strain showed the highest activity in winemaking conditions among the selected isolates. For aroma enhancement in winemaking, the glycosidase extract from H. uvarum strain exhibited catalytic specificity for aromatic glycosides of C13 -norisoprenoids and some terpenes, enhancing fresh floral, sweet, berry, and nutty aroma characteristics in wine.

This work presents a novel extracellular glycosidase preparation from an indigenous Rhodotorula mucilaginosa strain selected from a local winemaking region in China. This enzyme extract exhibits strong tolerance towards winemaking conditions. It shows hydrolysis specificity for glycosides of benzenic compounds and C13 -norisoprenoids, proving a potential candidate for improving floral and fruity aroma characteristics of wine.

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This article focuses on the relation between laccase-secreting ability and growing cycle in the edible fungi. First, laccase activities of fifteen different edible fungi were detected and determined by plate assay and spectrophotometric method using 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) as the substrate. The results showed the laccase-secreting ability in the edible fungi and their growing cycles are closely related. The edible fungi strains with short growing cycles originate from their high levels of secreted laccase activity. However, those strains require long growing cycles due to the low levels of secreted laccase, even no detectable laccase activity. The research provides the first evidence on the corresponding relation between the level of secreted laccase activity and growth cycles of edible fungi. Our study has significantly increased the understanding of the role of laccase in the growth and development of edible fungi.