Antigenotoxic effects of water extract from Korean fermented soybean paste (Doen-jang)

Aflatoxin B-1 is a major metabolite of the toxigenic molds Aspergillus flavus and Aspergillus parasiticus. In this study, a bacterial reverse mutation assay with Salmonella Typhimurium strains TA1535, TA1537, TA98, TA100, and TA102 and an in vitro chromosome aberration test with Chinese hamster lung (CHL) cells were used to investigate the genotoxicity of water extract from Korean soybean paste (doen-jang [dwen-jahng]) and its antigenotoxic activity against aflatoxin B-1. The water extract itself did not exhibit cytotoxicity or mutagenicity. The extract significantly reduced the numbers of revertants when it was added to the assay system with Salmonella Typhimurium TA100 (P < 0.05). The extract also exhibited significant inhibitory effects on chromosome aberration in CHL cells (P < 0.05). Dose-response relationships were observed between the concentration of the water extract and both its antimutagenic effect and its suppression of chromosome aberration. The results of this work indicate that water extract from Korean soybean paste could have potential as an antigenotoxic substance.