Edible Burdock

Common/vernacular names Bardana, beggar s buttons, burdock, edible burdock, great bur, great burdock, clotbur, lappa. 

The roots of Arctium lappa (edible burdock, Gobo), which are used for food in Japan, are especially rich in both aliphatic acetylenes and acetylenic dithiophenes (Figure 5.6 and Table 5.1). Most of the aliphatic acetylenes isolated from A. lappa (17, 23-28, 35-38) are widely distributed in Asteraceae, whereas the dithiophenes (58-69) isolated from this species are not very common as only a few have been isolated from other plant species... 

Figure 5.6 Dithiophenes isolated from the roots of Arctium lappa (edible burdock).

Figure 5.7 The possible biosynthesis of dithiophenes isolated from the roots of Arctium lappa (edible burdock). [O] = oxidation, [H] = reduction, — [H] = dehydrogenation (oxidation followed by the loss of water), [H2S] = addition of H2S or the biochemical equivalent to H2S, [CH3] = methylation due to the cofactor S-adenosyl methionine, SQL = sesquiterpene lactone (a guaianolide).

Recently, Maruta et al. [112] have found that methanol extracts of roots of burdock show a significant antioxidant activity in an in vitro lipid peroxidation assay, and have isolated five caffeoylquinic acid derivatives (CQAs) from the roots of burdock (Arctium lappa L ), an edible plant in Japan. Antioxidant activities of DCQAs and related compounds have been investigated by measuring the hydroperoxidation of methyl linolate via radical chain reaction. This study indicates that in this particular system caffeic acid and CQAs are more effective than a-tocopherol. These results approximately agree with our findings [38], Additionally, CQAs as the principle antioxidative substance in burdock root have been characterized. 

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