Verbascose roots

In 1910, Bourquelot and Bridel reported17 the isolation of a new oligosaccharide, verbascose, from the roots of the mullein, Verbascum thapsus. 

In 1940, Murakami published a study21 of the constitution of verbascose. To prepare this sugar, Murakami extracted the finely ground roots with 95% alcohol, clarified the extract with lead acetate, and precipitated the verbascose with barium hydroxide and alcohol. After processing the barium complex in the usual way, and precipitating the saccharide several times from an aqueous solution by alcohol, Murakami obtained verbascose in 0.5-mm. spherocrystals composed of fine needles these had m.p. 253°, [a]20D + 170.2° (in water). The elementary analysis and the cryoscopic molecular-weight values were appropriate for a pentasaccharide. 

Finally, in 1910, he isolated (with Bridel), from the roots of Verbascum thapsiforme, a pentasaccharide which he called verbascose and which contained (per molecule) three molecules of n-galactose associated with one of sucrose. 

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