Microalgae extract in winemaking: A bio-based alternative to sulfites to fight Brettanomyces bruxellensis

Abstract

Research on microalgae as a reservoir of metabolites with antifungal potential for innovative oenological applications remains unexplored. This study demonstrated, under oenological conditions, the efficacy of a novel treatment based on an algal extract from Amphidinium carterae to inhibit Brettanomyces bruxellensis growth in red wines over 150 days. Throughout the experiment, viable and culturable cell concentrations were monitored. To determine the impact of the treatment on volatile phenol production by B. bruxellensis, concentrations of 4-ethylphenol and 4-ethylguaiacol were quantified. The contribution of amphidinols (AMs) to the extract’s biocidal activity was also demonstrated under oenological conditions. In addition, the degradation of amphidinol 18 in the wine matrix was tracked by HPLC to evaluate the persistence of the active compound. The extract completely suppressed both B. bruxellensis growth and volatile phenol production throughout the monitoring period, regardless of the strain tested, including strains resistant to conventional treatments. Treatment performance depended on the initial contamination level. Finally, amphidinol 18 progressively degraded in red wine and became undetectable after 30 days. Overall, these findings underscore the potential of amphidinols as a promising alternative to sulfites for controlling B. bruxellensis in oenology.

References

Abry, C., Bauvois, C., De Crasto, L., Tourbier, E., Lecourt, J., & Alexandre, H. (2025). Algal amphidinols, an alternative to sulfites in the fight against Brettanomyces bruxellensis. LWT, 235, 118633.