Impact of sulphur dioxide on the viability, culturability, and volatile phenol production of Dekkera bruxellensis in wine

Viable But Not Culturable (VBNC) state of Brettanomyces bruxellensis in wine: New insights on molecular basis of VBNC behaviour using a transcriptomic approach

“…Our findings are in accordance with other studies on the variability of strains sensitivity to SO 2 (Agnolucci et al, 2010;Du Toit et al, 2005;Serpaggi et al, 2012). In addition, our results strongly confirm Table 2 Genes coding for proteins involved in the oxidative stress response found significantly differentially expressed (Log2 fold change) i) in the comparison between cells growth without treatment and cells in VBNC state (C vs E) and ii) comparing cells in VBNC state vs cells in the recovery phase (E vs R).. evidences already reported by Zuehlke and Edwards (2013) and by Agnolucci et al (2013) on the strain-dependent variability of VBNC state. Moreover, we evidenced that the VBNC behaviour in B. bruxellensis varies in a strain-dependent manner as a function of molecular SO 2 concentration.…”

“…Referring to the winery environment, several studies have shown that sulphur dioxide, an antimicrobial agent used in food preservation, induces the VBNC state in B. bruxellensis (Du Toit et al, 2005;Agnolucci et al, 2010;Serpaggi et al, 2012;Zuehlke and Edwards, 2013;Agnolucci et al, 2013). Serpaggi et al (2012) demonstrated that the strains may 'resuscitate', returning to a culturable state, by increasing the pH in order to remove the SO 2 from the medium (Serpaggi et al, 2012).…”

“…Concerning intraspecific variability, Zuehlke and Edwards (2013), aiming to assess the good combination of molecular SO 2 and temperature to limit the spoilage by Brettanomyces, described a certain diversity in culturability among three B. bruxellensis strains using fluorescence microscopy. Recently, Agnolucci et al (2013), analysed by vital staining with tripan-blue seven strains representative of 85 isolates from Sangiovese grapes in different Tuscan wineries of the Chianti area. The results reported indicated that concentrations up to 1 mg/L of molecular sulphur dioxide induced the non-culturable state to a different extent after 24 h of exposure (Agnolucci et al, 2013).…”

“…Recently, Agnolucci et al (2013), analysed by vital staining with tripan-blue seven strains representative of 85 isolates from Sangiovese grapes in different Tuscan wineries of the Chianti area. The results reported indicated that concentrations up to 1 mg/L of molecular sulphur dioxide induced the non-culturable state to a different extent after 24 h of exposure (Agnolucci et al, 2013).…”

Inactivation of Dekkera bruxellensis yeasts in wine storage in brand new oak barrels using low electric current technology

“…Others have observed yeast growth even with concentrations of free SO 2 above 30 mg/L, reflecting the resistance of certain D. bruxellensis strains (Agnolucci et al 2010). The heart of this controversy, however, does not lie in the free form of SO 2 , but rather in the actual effectiveness of its molecular form (Ribereau-Gayon et al 2006;Agnolucci et al 2014), which is dependent on many variations in wine composition, including pH, ethanol content, temperature, anthocyanin levels, and nutrient content (Blomqvist et al 2012). The effectiveness of molecular SO 2 on a strain of B. bruxellensis has also been linked with oxygen availability (du Toi et al 2005).…”