WASABI

Wasabi is a perennial herb belonging to the Brassicaceae or mustard family. It forms underground the typical rhizomes which can be 30 cm long. The wasabi leaves are long, toothed and have palmate veins. It forms typical white Cruciferae flowers that are arranged on racemes.

Parts used

Mainly the roots (rhizomes) are used, but also fresh wasabi leaves can be eaten, having the same spicy flavor.

Phytochemicals

These are typical phytochemicals found in wasabi: 6-(methylsulfinyl)hexyl isothiocyanate, monogalactosyl diacylglycerides, isothiocyanates.

Scientific studies about wasabi

Anti-cancer effects

Wasabi contains isothiocyanates, which are known to neutralize carcinogens and inhibit the growth of cancer cells [1-5]. Especially the isothiocyanate 6-(Methylsulfinyl)hexyl isothiocyanate has been studied extensively for its anti-cancer effects.
Anti-bacterial effects
The wasabi root may suppress bacteria responsible for gastric inflammation. Shin and co-workers at the Kangnung National University, South Korea, explored the bactericidal activity of wasabi roots, stems and leaves against Helicobacter pylori[6]. They found that all parts of wasabi showed bactericidal activities against different H. pylori strains. Allyl isothiocyanates are the main antibacterial phytochemicals, but other components may play a role since wasabi leaves showed stronger activity than wasabi roots, while the roots contained higher levels of allyl isothiocyanates.

Traditional use

In Japan wasabi is often eaten with raw fish to prevent food poisoning but this method is not very reliable.

Other facts

Wasabi grows naturally along stream beds in mountain river valleys in Japan. Mayn restaurants substitute wasabi with less expensive European horseradish. However, European horseradish does not contain the longer-chain isothiocyanates, such as 6-MITC.

Other names

Japanese horseradish

References

[1] Suppressive effect of wasabi (pungent Japanese spice) on
gastric carcinogenesis induced by MNNG in rats.
Nutr Cancer. 1991;16(1):53-8.

[2] Dynamics of Nrf2 and Keap1 in ARE-mediated NQO1 expression
by wasabi 6-(methylsulfinyl)hexyl isothiocyanate.
J Agric Food Chem. 2011 Nov 23;59(22):11975-82.

[3] Selective sensitivity to wasabi-derived 6-(methylsulfinyl)
hexyl isothiocyanate of human breast cancer and
melanoma cell lines studied in vitro.
Cancer Detect Prev. 2005;29(2):155-60.

[4] Tumor cell proliferation and cyclooxygenase inhibitory constituents
in horseradish (Armoracia rusticana) and Wasabi (Wasabia japonica).
J Agric Food Chem. 2005 Mar 9;53(5):1440-4.

[5] Colon cancer proliferating desulfosinigrin in
wasabi (Wasabia japonica).
Nutr Cancer. 2004;48(2):207-13.

[6] Bactericidal activity of wasabi (Wasabia japonica)
against Helicobacter pylori.
Int J Food Microbiol. 2004 Aug 1;94(3):255-61.