Backgrounds: We reported that feeding 5% Asperagillus awamori-fermented burdock root diet was effective in preventing mouse hyperglycemia caused by alloxan.

Methods: Diets containing 5% burdock roots were prepared from raw and Asperagillus awamori-fermented burdock root powders. Acatalasemic mice, having a quite low catalase activity in blood, and normal mice were fed these diets for 14 weeks, separately. Then, alloxan (200 mg/ kg of body weight) or PBS was intraperitoneally administrated to each mouse. After 5 day from the administration, blood glucose assay and glucose tolerance test were carried out, and then insulin, C-peptide and lipid peroxide in plasma were examined.

Results: Incidences of hyperglycemia in normal mice fed control, raw and fermented burdock root diets were 25, 20 and 11 %, respectively, and these in acatalasemic mice were 73, 80 and 27%. Insulin and C-peptide in plasma of mice fed raw burdock root diet or control diet were low compared to mice fed the fermented diet.

Conclusions: Intake of raw burdock root does not suppress the alloxan-induced hyperglycemia but the fermented burdock root does. It is suggested that Asperagillus awamori plays an important role for the prevention.