Effect of Lactobacillus acidophilus KFRI342 on the development of chemically induced precancerous growths in the rat colon.

Lactobacillus acidophilus KFRI342, isolated from the Korean traditional food kimchi, was investigated for its suitability as a dietary probiotic. The effects of L. acidophilus KFRI342 on the development of chemically induced (1,2-dimethylhydrazine; DMH) precancerous cytological changes of the colon were investigated in rats. Forty-five male F344 rats were randomly divided into three dietary groups. The control group received a high-fat diet (HF), a second group received a high-fat diet containing the carcinogen (HFC), and a final group received a high-fat diet containing the carcinogen and L. acidophilus KFRI342 (HFCL). L. acidophilus KFRI342 was administered orally three times per week at 2×10(9) c.f.u. ml(-1). L. acidophilus KFRI342 treatments decreased the number of Escherichia coli in faecal samples, the enzyme activities of β-glucuronidase and β-glucosidase, and plasma triglyceride concentration compared to the HF and HFC treatments (P<0.05). L. acidophilus KFRI342 consumption also decreased the ratio of aberrant crypts to aberrant crypt foci incidence and the number of aberrant crypts in HFCL rats. Therefore, L. acidophilus showed potential probiotic activity as an inhibitor of DMH-induced symptoms in live rats. Our in vivo studies indicate that L. acidophilus from kimchi may be suitable as a probiotic for human use.