Hydrolysis of isoflavone glucosides in soymilk fermented with single or mixed cultures of Lactobacillus paraplantarum KM, Weissella sp. 33, and Enterococcus faecium 35 isolated from humans

J Microbiol Biotechnol. 2008 Mar;18(3):573-8.

Abstract

Lactobacillus paraplantarum KM (Lp), Weissella sp. 33 (Ws), and Enterococcus faecium 35 (Ef) were used in single (Lp, Ws, Ef) or mixed cultures (Lp+Ws, Lp+Ef, Ws+Ef) for soymilk fermentation (37 degrees C, 12 h). After 12 h, the cell numbers, pH, and TA of soymilk were 7.4x108 -6.0x109 CFU/ ml, 3.8-4.5, and 0.59-0.70%, respectively. Changes in the contents of glycitin and genistin in soymilk fermented with Ef were not significant (p<0.05). The contents of isoflavone glucosides in soymilk fermented with the other cultures decreased significantly with an increase of aglycone contents (p<0.05). It corresponded well with a sharp increase in beta- glucosidase activity during fermentation. About 92-100% of the daidzin and 98-100% of the genistin in soymilk were converted to corresponding aglycones by Lp, Ws, or Lp+Ef within 12 h.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacteria / growth & development
  • Bacteria / metabolism*
  • Enterococcus faecium / growth & development
  • Enterococcus faecium / metabolism
  • Feces / microbiology*
  • Fermentation*
  • Glucosides / metabolism*
  • Humans
  • Hydrolysis
  • Isoflavones / metabolism*
  • Lactic Acid / metabolism
  • Lactobacillus / growth & development
  • Lactobacillus / metabolism
  • Soy Milk / metabolism*
  • beta-Glucosidase / metabolism

Substances

  • Glucosides
  • Isoflavones
  • Lactic Acid
  • beta-Glucosidase