Screening and evaluation of the glucoside hydrolase activity in Saccharomyces and Brettanomyces brewing yeasts

Abstract

Aims: The aim of this study was to select and examine Saccharomyces and Brettanomyces brewing yeasts for hydrolase activity towards glycosidically bound volatile compounds. Methods and Results: A screening for glucoside hydrolase activity of 58 brewing yeasts belonging to the genera Saccharomyces and Brettanomyces was performed. The studied Saccharomyces brewing yeasts did not show 1,4‐β‐glucosidase activity, but a strain dependent β‐glucanase activity was observed. Some Brettanomyces species did show 1,4‐β‐glucosidase activity. The highest constitutive activity was found in Brettanomyces custersii. For the most interesting strains the substrate specificity was studied and their activity was evaluated in fermentation experiments with added hop glycosides. Fermentations with Br. custersii led to the highest release of aglycones. Conclusions: Pronounced exo‐β‐glucanase activity in Saccharomyces brewing yeasts leads to a higher release of certain aglycones. Certain Brettanomyces brewing yeasts, however, are more interesting for hydrolysis of glycosidically bound volatiles of hops. Significance and Impact of the Study: The release of flavour active compounds from hop glycosides opens perspectives for the bioflavouring and product diversification of beverages like beer. The release can be enhanced by using Saccharomyces strains with high exo‐β‐glucanase activity. Higher activities can be found in Brettanomyces species with β‐glucosidase activity.

The Microbiology of Malting and Brewing

“…␤-Glycosidases in Saccharomyces cleave nonvolatile glycosides derived from hops, fruit, and other plants used in brewing, cleaving a sugar moiety from the aglycon. The free aglycon may exhibit aromatic activity in this state and represents a largely untapped source of aroma in beer (142). However, there are doubts about whether the cellular location of ␤-G is commensurate with an ability to release such aroma compounds (143).…”

Microbial β-Glucosidases: Screening, Characterization, Cloning and Applications

“…Contrarily, cyclohexenoesculetin-β-glucoside allows the growth of gram-positive bacteria and does not suffer from the diffusion of the 8-hydroxyquinoline-iron complex throughout the plate [40]. The ferric salt may inhibit the growth of microorganisms and misinterpretation of the results may occur [37,41].…”

“…Aglycone then chelates ferric ions supplemented to the growth medium (Figure 1), and forms dark brown complex against clear background [36,37]. The main disadvantage for using esculin is diffusion of esculetin-iron complex throughout medium making it difficult to distinguish β-glucosidase producing colonies from non-producers [38].…”

beta-(1,3)-Glucanases Fúngicas: Produção e Aplicações Biotecnológicas.

“…As β-1,3-glucanases são produzidas por bactérias (FLEURI; SATO, 2008), leveduras (NEBREDA et al, 1987, DAENEN et al, 2008, e fungos filamentosos (VÁSQUEZ-GARCIDUEÑAS; LEAL-MORALES;…”

“…Os tempos de incubação para a determinação da atividade de β-1,3-glucanase descritos na literatura variam em intervalos de 10 a 20 minutos (GIESE et al, 2005;SIM, HANG, 1996) ou bem maiores como 1 hora (VÁSQUEZ-GARCIDUEÑAS; LEAL-MORALES; HERRERA-ESTRELLA, 1998;DAENEN et al, 2008;PENG et al, 2009 As β-glucanases também podem ter a atividade inibida pela presença de compostos como clorofórmio, benzenóides, organofosfatos e quelantes, entre outros, bem como pela concentração de substrato ou de produtos formados durante a reação (RANA et al, 2003 (YI et al, 2008).…”