Abstract
We investigated the influence of the extract of soy protein fermented with lactic acid bacteria and yeast (ESFL) on 1, 2-dimethylhydrazine (DMH)-induced colon cancer and aberrant crypt foci (ACF) in ICR female mice. In all the experiments, 8-week old mice were given subcutaneous DMH injections at 35 mg/kg once a week. In the experiment for colon cancer, mice were divided into groups A, B and C, with 20 mice each, and groups A and B were given DMHinjections for 10 weeks. Group C were injected with only PBS. Group A were fed a 5%-ESFL diet and groups B and C were fed normal mouse diets throughout the experiment for 35 weeks. Group A showed a 28.5% inhibition in incidence and a 59.1% inhibition in average number of tumors compared to group B, but the results were not statistically significant. In ACF experiments, mice were divided into 4 groups, 10%-ESFL group, 1%-ESFL group, 0.1%-ESFL group, and a control with 10 mice each. All the mice were given DMH injections for 4 weeks. ESFL-supplemented diets were given throughout the experiment for 8 weeks. ACF formation decreased in all the ESFL-fed groups in a dose-dependent manner and the results were statistically significant in the 10%-ESFL group (69% inhibition, p<0.001) and 1%-ESFL group (40% inhibition, p<0.05) compared to the control. The present study suggests that ESFL could contain an effective anticarcinogenic substance (s).
