Flavonoid aglycone and glycoside cpds. purification - by selective adsorption on oxide, hydroxide or basic salt of divalent metals

摘要

Flavonoid aglycones and glycosides are isolated from extracts by forming complexes of the flavonoids with metal ions. In this process, solns. of the flavonoids in organic solvents (which may contain small amts. of water) are subjected to column chromatography using as sorbents granular oxides, hydroxides or basic salts of divalent cations which (a) are insoluble in the organic solvent used, (b) are soluble in dilute acids and (c) have a pH of 7-13 in aq. suspension. One or more columns contg. different sorbents as defined above may be arranged in series. Impurities are washed from the column by elution with organic solvents in which the sorbents are insoluble, then the flavonoids are recovered by dissolving in dilute acids and isolating from the resulting acidic soln. Plant flavonoids have a favourable effect on the heart and blood vessels. The process is suitable for use on a technical scale. It gives smooth removal of impurities without loss of flavonoids.