title: Aflatoxin B1 Degradation by Metabolites of Phoma glomerata PG41 Isolated From Natural Substrate Colonized by Aflatoxigenic Aspergillus flavus.
abstract: BACKGROUND
  Aflatoxin B1 (AFB1), produced by Aspergillus flavus, is one of the most life threatening food contaminants causing significant economic losses worldwide. Biological AFB1 degradation by microorganisms, or preferably microbial enzymes, is considered as one of the most promising approaches.
  
  
  OBJECTIVE
  The current work aimed to study the AFB1-degrading metabolites, produced by Phoma glomerata PG41, sharing a natural substrate with aflatoxigenic A. flavus, and the preliminary determination of the nature of these metabolites.
  
  
  METHODS
  The AFB1-degrading potential of PG41 metabolites was determined by a quantitative high performance liquid chromatography (HPLC) of residual AFB1 after 72 hours incubation at 27ºC. The effects of pH, heat, and protease treatment on the AFB1-destroying activity of extracellular metabolites were examined.
  
  
  RESULTS
  The AFB1-degrading activity of protein-enriched fractions, isolated from culture liquid filtrate and cell-free extract, is associated with high-molecular-weight components, is time- and pH-dependent, thermolabile, and is significantly reduced by proteinase K treatment. The AFB1 degradation efficiency of these fractions reaches 78% and 66%, respectively.
  
  
  CONCLUSIONS
  Phoma glomerata PG41 strain sharing natural substrate with toxigenic A. flavus secretes metabolites possessing a significant aflatoxin-degrading activity. The activity is associated mainly with a protein-enriched high-molecular-weight fraction of extracellular metabolites and appears to be of enzymatic origin.
authors: All-Russian Research Institute of Phytopathology, Bolshie Vyazemy, Moscow Region, Russia.
authors: Larisa
authors: L
authors: Shcherbakova
authors: All-Russian Research Institute of Phytopathology, Bolshie Vyazemy, Moscow Region, Russia.
authors: Natalia
authors: N
authors: Statsyuk
authors: All-Russian Research Institute of Phytopathology, Bolshie Vyazemy, Moscow Region, Russia.
authors: Oleg
authors: O
authors: Mikityuk
authors: All-Russian Research Institute of Phytopathology, Bolshie Vyazemy, Moscow Region, Russia.
authors: Tatyana
authors: T
authors: Nazarova
authors: All-Russian Research Institute of Phytopathology, Bolshie Vyazemy, Moscow Region, Russia.
authors: Vitaly
authors: V
authors: Dzhavakhiya
keywords: Aflatoxin B1; Aspergillus flavus; Decontamination; Phoma glomerata