Evaluation of bioactive component in Wasabi and other cruciferae
Abstract
Wasabia japonica or wasabi is very popular in Japan while cauliflower (Brassica
oleracea var. italica), broccoli (B. oleraceavar. botrytis), White radish (Raphanus
sativus) is a very popular plant among Malaysians. This project was carried out to
determine the bioactive component in these samples after extraction with two different
solvents which are water and ethanol. It is also required to compare which method will
give the best yield of antioxidant after the extraction. Water extraction method was
better compared to ethanol extraction. The compound and type of bond in the extraction
samples was also determined by using the Fourier-Transform Infrared (FTIR). Listerine
sample was used as a control for antiseptic and antibacterial agents. Moreover, extract
of these edible plants also were determined for their antibacterial activity against grampositive
and gram-negative bacteria. It is also tested on fungi and yeast as revealed by
Kirby-Bauer method. From FTIR study the OH groups present denotes the presence of
alcohol and phenolic compounds in the Listerine as well as sample especially in wasabi
and radish showing the presence of antiseptic and antibacterial in the sample studied.
The Kirby-Bauer method measured antibacterial activity against gram-positive and
gram-negative bacteria. Isothiocyanate analysis was not able to determine using the
HPLC method due to unavailability of the standards. Other active ingredient such as
Rosmarinic acid, 3-Hydroxy 5,6,7,9 tetramethylflavone (TMF), Sinensitin and
Eupatorin were determined.