Wasabi (Wasabia japonica Matsum.) Rhizome Possesses Potent Amylolytic Activity

Wasabi (Wasabia japonica) is a traditional condiment used in Japanese dishes. The wasabi rhizome shows potent amylolytic activity. The amylase activities of 12 Brassicaceae vegetables, including wasabi and three non-Brassicaceae root vegetables, were determined and compared. Among the 15 vegetables, wasabi showed the highest amylase activity (203 U g-1 fresh weight). The second and third highest activities were found in horseradish (14 U g-1 fresh weight) and sweet potato (8.6 U g-1 fresh weight), respectively. The 12 other vegetables exhibited activities less than 3 U g-1 fresh weight. Immunoblot analyses using an anti-radish (Raphanus sativus) β-amylase antibody indicated that wasabi contained an abundance of the antigen. Tissue printing indicated that the β-amylase antigen is generally distributed throughout the wasabi rhizome. These results suggest that wasabi contains a large amount of β-amylase, and therefore shows strong amylolytic activity.