title: Identification of Dekkera bruxellensis as a major contaminant yeast in continuous fuel ethanol fermentation.
abstract: OBJECTIVE
  To identify and characterize the main contaminant yeast species detected in fuel-ethanol production plants in Northeast region of Brazil by using molecular methods.
  
  
  RESULTS
  Total DNA from yeast colonies isolated from the fermentation must of industrial alcohol plants was submitted to PCR fingerprinting, D1/D2 28S rDNA sequencing and species-specific PCR analysis. The most frequent non-Saccharomyces cerevisiae isolates were identified as belonging to the species Dekkera bruxellensis, and several genetic strains could be discriminated among the isolates. The yeast population dynamics was followed on a daily basis during a whole crop harvesting period in a particular industry, showing the potential of D. bruxellensis to grow faster than S. cerevisiae in industrial conditions, causing recurrent and severe contamination episodes.
  
  
  CONCLUSIONS
  The results showed that D. bruxellensis is one of the most important contaminant yeasts in distilleries producing fuel-ethanol from crude sugar cane juice, specially in continuous fermentation systems.
  
  
  CONCLUSIONS
  Severe contamination of the industrial fermentation process by Dekkera yeasts has a negative impact on ethanol yield and productivity. Therefore, early detection of D. bruxellensis in industrial musts may avoid operational problems in alcohol-producing plants.
authors.affiliation: Departamento de Genética, Universidade Federal de Pernambuco, Recife, PE, Brazil.
authors.forename: A T
authors.initials: AT
authors.lastname: de Souza Liberal
authors.forename: A C M
authors.initials: AC
authors.lastname: Basílio
authors.forename: A
authors.initials: A
authors.lastname: do Monte Resende
authors.forename: B T V
authors.initials: BT
authors.lastname: Brasileiro
authors.forename: E A
authors.initials: EA
authors.lastname: da Silva-Filho
authors.forename: J O F
authors.initials: JO
authors.lastname: de Morais
authors.forename: D A
authors.initials: DA
authors.lastname: Simões
authors.forename: M A
authors.initials: MA
authors.lastname: de Morais
mesh_terms: D001938:Brazil; D016172:DNA Fingerprinting; D004271:DNA, Fungal / Q000032:analysis*; D004736:Energy-Generating Resources; D000431:Ethanol; D005285:Fermentation; D007218:Industrial Microbiology; D012441:Saccharomyces cerevisiae / Q000235:genetics; D004718:Saccharomycetales / Q000235:genetics*; D031786:Saccharum
chemical_list: D004271:DNA, Fungal; D000431:Ethanol