Abstract
To investigate the inhibitory effect of soybean and Korean traditional fermented soybean products on the chemically induced mutagenesis, we extracted soybean, Kanjang, Doenjang, Kochujang, and Chongkukjang with water, methanol and hexane. Inhibitory effect of the extracts was assayed by the SOS chromotest using Escherichia coli PQ37 as a test strain. 4-nitroquinoline-1-oxide(4NQO), N-methyl-N'-nitro-N-nitrosoquanidine(MNNG), and aflatoxin B$_{1}$(AFB$_{1}$) were used as mutagens. Methanol extracts showed relatively higher inhibitory effect than water and hexane extracts. Methanol extracts of soybean, Doenjang, Kochujang, and Chonhkukjang showed inhibitory effect of 68.4, 96.3, 17.5, and 100.9% against MNNG, and 28.6, 109.1, 41.3, and 101.8% against AFB$_{1}$, respectively. Doenjang methanol extract showed inhibitory effect of 51.0, 96.3, and 109.1% against 4NQO, MNNG, and AFB$_{1}$, respectively. Methanol extract of Doenjang showed dose-dependent inhibitory effect against 4NQO, MNNG, and AFB$_{1}$. Inhibitory effect of heat-treated Doenjang and Chongkukjang methanol extracts on the mutagenecity of MNNG and AFB$_{1}$ was remained over 95% of the inhibitory effect of heat-untreated extracts, demonstrating the heat stability of the potent antimutagenic activity.