Characteristics of fermentation and bioavailability of isoflavones in Korean soybean paste (doenjang) with application of Bacillus sp. KH-15

Yang Mun Choi, Yoon Sook Kim, Kyung Soo Ra, Hyung Joo Suh

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11 Citations (Scopus)


We attempted to increase the fibrinolytic activity and aglycone contents of isoflavone in doenjang prepared with Bacillus sp. KH-15. An initial rapid increase of viable cells was observed in the first 30 days followed by a gradual decrease to 1.78 × 108 CFU g-1 wet weight. The amino type nitrogen sharply was increased after 15 days, and showed the highest level (788.7 mg%) after 90 days. The total nitrogen was increased from 2.21% to 2.52% of final content after 90 days. Soluble carbohydrate was increased to 32.9 mg g-1 for 60 days, and after 60 days, the content was slowly decreased to 29.5 mg g-1. A rapid increase in fibrinolytic and caseinolytic activities were observed in the first 30 and 45 days of fermentation followed by a gradual decrease to 2.54 and 144.5 U g-1, respectively. γ-Glucosidase activity also showed a similar change pattern of the caseinolytic and fibrinoytic activities. Daidzein and genistein were increased to the maximum level of 764.5 and 561.4 mg kg-1 at day 30, respectively. At day 90, the contents of daidzein and genistein were 661.5 and 524.9 mg kg-1, respectively. The rats were fed a diet supplemented with either doenjang powder prepared with Bacillus sp. KH-15 (D-1 group) or commercial doenjang powder (D-2 group) for 40 days. The level of serum total isoflavones in the D-1 group was significantly higher than that in the D-2 group.

Original languageEnglish
Pages (from-to)1497-1503
Number of pages7
JournalInternational Journal of Food Science and Technology
Issue number12
Publication statusPublished - 2007 Dec 1



  • β-glucosidase activity
  • Bacillus sp.
  • Daidzein
  • Doenjang
  • Fibrinolytic activity
  • Genistein
  • Soybean paste

ASJC Scopus subject areas

  • Food Science

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