title: Enhanced in vitro and in vivo antioxidant activity and mobilization of free phenolic compounds of soybean flour fermented with different beta-glucosidase-producing fungi.
abstract: OBJECTIVE
  To evaluate the soybean polyphenol glucosides bioconversion to aglycone forms by different beta-glucosidases-producing filamentous fungi to enhance their antioxidant activity.
  
  
  RESULTS
  Soybean defatted flour was submitted to solid-state fermentation with Aspergillus niger, Aspergillus niveus and Aspergillus awamori. The fungi studied produced approximately the same beta-glucosidase activity units amount when p-nitrophenyl-beta-d-glucopyranoside was used as substrate for the assay. However, electrophoretic analysis, using 4-methylumbellipheryl-beta-d-glucopyranoside as substrate, showed that beta-glucosidase produced by A. niveus was more active. Fermented methanolic extracts showed an increase in polyphenol and genistein contents and antioxidant activities. The highest genistein content was found in soybean fermented by A. niveus. Methanolic extracts of the soybean fermented by the different fungi showed a similar capacity of scavenging H(2)O(2) generated in vivo by the tumour promoter 12-O-tetradecanoyl phorbol-13-acetate.
  
  
  CONCLUSIONS
  A. niveus synthesized a beta-glucosidase with higher specificity to hydrolyse genistin beta-glycosidic bond than those produced by A. awamori and A. niger.
  
  
  CONCLUSIONS
  The utilization of these beta-glucosidases-producing fungi in soybean fermentation processes resulted in the obtaining of methanolic extracts with different antioxidant potentials that could be used either therapeutically or as an antioxidant in nonphysiological oxidative stress conditions, as the one induced in skin by UV radiation.
authors.affiliation: Department of Pharmaceutical Sciences, Faculty of Pharmaceutical Sciences of Ribeirao Preto, University of Sao Paulo-USP, Brazil.
authors.forename: S R
authors.initials: SR
authors.lastname: Georgetti
authors.forename: F T M C
authors.initials: FT
authors.lastname: Vicentini
authors.forename: C Y
authors.initials: CY
authors.lastname: Yokoyama
authors.forename: M F
authors.initials: MF
authors.lastname: Borin
authors.forename: A C C
authors.initials: AC
authors.lastname: Spadaro
authors.forename: M J V
authors.initials: MJ
authors.lastname: Fonseca
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D001230:Aspergillus / Q000201:enzymology*; D044602:Cellulases / Q000378:metabolism*; D005285:Fermentation; D005419:Flavonoids / Q000378:metabolism*; D005433:Flour; D005516:Food Microbiology; D019833:Genistein / Q000032:analysis; D005960:Glucosides / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000378:metabolism; D051379:Mice; D010636:Phenols / Q000378:metabolism*; D059808:Polyphenols; D045730:Soy Foods; D013025:Glycine max / Q000737:chemistry*
chemical_list: D000975:Antioxidants; D005419:Flavonoids; D005960:Glucosides; D010636:Phenols; D059808:Polyphenols; D006861:Hydrogen Peroxide; D019833:Genistein; D044602:Cellulases