Differential immunomoulatory effects of Chungkukjang on murine peritoneal macrophage and splenocyte

Chungkukjang is a unique Korean traditional food fermented by soybean. Although several biological studies of chungkukjang have been performed, its effect on immune cells remains unclear. The objective of this study was to compare immunomodulatory effects of chungkukjang fermented from soybean using Bacillus cereus (BC), Lactic acid bacteria (LAB) and mixed strains (BC and LAB), respectively. C57BL/6 male mice were orally administrated four different groups of Chungkukjang for 60 days. The present data showed that phagocytic and tumoricidal activity of macrophage were significantly decreased in orally administrated soybean, LAB and mixed strains groups, whereas orally administrated BC group resulted in an increase of phagocytic and tumoricidal activity. Moreover, the levels of cytokines (GM‐CSF and IL‐6) were increased, whereas the production of NO was decreased in orally administrated BC and LAB groups. Concanavalin A‐induced splenic T cell proliferation and LPS‐stimulated B cell proliferation were decreased in orally administrated all groups. Tumoricidal activity of NK cell was decreased in orally administrated soybean, BC and LAB groups, whereas the activity was significantly increased in orally administrated mixed strains group. Taken together, these results suggest that chungkukjang fermented by different sources has differential immunomodulatory effects on macrophage and splenocyte.