The invention provides compositions and methods for isolating phenolic compounds,
particularly isoflavones, from aqueous extracts of plant materials that contain
such compounds. The process comprising:
- (a) providing an aqueous plant extract at a first pH less than 10, the
aqueous plant extract comprising a plurality of phenolic compounds;
- (b) extracting the aqueous plant extract with a first organic solvent
to yield a first organic extract;
- (c) extracting the first organic extract with an aqueous phase of pH
greater than 10 to yield a phenol rich aqueous phase;
- (d) adjusting the pH of the phenol rich aqueous phase to a pH of less
than 9; and
- (e) isolating the phenolic compounds from the phenol rich aqueous phase.