In the present study, the effects of β-
glucans isolated from Euglena on the formation of preneoplastic
aberrant crypt foci (ACF) in the colon were examined in mice. Mice were fed a semi-purified AIN-93M diet containing
cellulose or the same diet but with the
cellulose replaced with β-
glucans in the form of Euglena,
paramylon, or amorphous
paramylon, for 11 weeks. After consuming these dietary supplements for 8 days, half of the mice were intraperitoneally administered
1,2-dimethylhydrazine (
DMH) at a dose of 20 mg kg(-1)
body weight every week for 6 weeks. Among the
DMH-treated groups, the
paramylon- and amorphous
paramylon-fed mice displayed a significantly lower number of ACF than the control group. Also, the liver weight of the
paramylon group was markedly decreased compared with those of the control and Euglena groups, whereas the cecal content weight and fecal volume of the
paramylon group were significantly increased. As for the levels of organic
acids in the cecal contents, the
paramylon group displayed significantly increased
lactic acid levels compared with the control and Euglena groups. From these findings, although the mechanism of the ACF-inhibiting effects of
paramylon remains unclear, it is considered that β-
glucans, such as
paramylon and its isomer amorphous
paramylon, have preventive effects against
colon cancer and are more effective against the condition than Euglena.