Etilphenol production by Dekkera bruxellensis strains isolated from the ethanolic fermentation: enzymatic evaluation and the effects of the etilphenols on industrial strains of Saccharomyces cerevisiae

• Grant number: 16/20680-4
• Support Opportunities: Regular Research Grants
• Start date: February 01, 2017
• End date: January 31, 2019
• Field of knowledge: Biological Sciences - Microbiology - Applied Microbiology
• Principal Investigator: Sandra Regina Ceccato Antonini
• Grantee: Sandra Regina Ceccato Antonini
• Host Institution: Centro de Ciências Agrárias (CCA). Universidade Federal de São Carlos (UFSCAR). Araras , SP, Brazil

Abstract

Brazil is the greatest ethanol exporter and the second world producer. The fermentation process has some peculiarities as the fact that it does not occur in aseptic conditions. Therefore, contaminations by wild (native) yeasts or bacteria may result in lower fermentative efficiency. One of the most important yeast contaminant of the fermentation is Dekkera bruxellensis, which displays ethanol yield similar to Saccharomyces cerevisiae, however low ethanol productivity. In the presence of oxygen, D. bruxellensis produces great amounts of acetic acid, an inhibitor for S. cerevisiae, however the fermentation process is essentially anaerobic and in this condition, the acetic acid production is extremely low. Other metabolic ways may act in the fermentation system, as the etilphenol production, which may be harmful to S. cerevisiae viability. In wine, the ability of D. bruxellensis strains to produce phenolic compounds like etilphenols from hydroxycinnamic acids present in the grapes due to the action of the enzymes hydroxycinnamate decarboxylase and vinylphenol reductase is extensively reported. Hydroxycinnamic acids are also present in the sugar cane juice and molasses and so, etilphenols may be synthesized during the alcoholic fermentation. Therefore, this project aims to evaluate whether D. bruxellensis strains (isolated from ethanolic fermentation) are able to produce etilphenols during the industrial conditions of fermentation (sugarcane musts and cell recycle) in concentrations high enough to inhibit S. cerevisiae and to determine the enzymatic activity associated to this production. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

LIMA SILVA, LINCON FELIPE; RECO, ALINE SOTTA; PENA, RUBEN; GANGA, MARIA ANGELICA; CECCATO-ANTONINI, SANDRA REGINA. Volatile phenols are produced by strains of Dekkera bruxellensis under Brazilian fuel ethanol industry-like conditions. FEMS Microbiology Letters, v. 365, n. 21, NOV 2018. (16/20680-4)