Antigenotoxic, Fibrinolytic and Immunomodulating Activity of Traditionally Fermented Soy Product, Chungkukjang

Abstract

Fibrinolytic, antigenotoxic and immunomodulating properties of chungkukjang were evaluated. The purified fibrinolytic enzyme was characterized as an alkaline serine protease with molecular weight of 22 kDa determined by fibrin zymography and stable over pH range 6.0–10.0 below 50C. The comet assay showed that N‐methyl‐N′‐nitro‐N‐nitrosoguanidine (MNNG)‐induced DNA damage level (190.8 AU) in 3T3 cells was considerably decreased to 121.2 AU with chungkukjang extracts (CB) showing 49.7% of protection. Incubation of the 3T3 cells with CB significantly reduced the cytotoxicity of MNNG. [3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide] (MTT) assay revealed that the addition of CB enhanced the proliferation of RAW 264.7 (mouse leukemic monocyte macrophage cell line) macrophages up to about 150% of the control levels. RAW 264.7 macrophages incubated with CB induced a strong increase in nitric oxide (NO), tumor necrosis factor‐α (TNF‐α) and interleukin‐1α (IL‐1α) with a dose‐dependent manner. After 24 h incubation with 1 mg/mL of CB, NO, TNF‐α and IL‐1α showed the highest production of 511, 2.46 and 0.258 ng/mL, respectively.