Patent ID: 6897298

Claim:
A method for extracting a compound of a formula (I), comprising: (1) providing a corpus radicis and/or radix fibrosa of a ginseng spp. plant, ginseng or pseudo-ginseng, crushing roots, cold extracting once with industrial alcohol, hot extracting 0-3 times, combining the filtrates, and then extracting with n-butanol to obtain coarse total saponins; (2) separating the coarse total saponins with gradient elution solutions by silica gel column chromatography, the gradient elution solutions comprising chloroform, methanol and optionally water, and then condensing a desired fraction to obtain a condensed solution in a form of a decocted paste; and (3) dissolving the condensed solution with an appropriate amount of methanol, separating and purifying the solution with the gradient elution solutions on a reverse phase column, the gradient elution solutions comprising methanol and water, and collecting the desired fraction; recovering the methanol from the collected desired fraction, and allowing the fraction to stand for more than 24 hrs to separate out a white precipitate, and drying the precipitate to obtain a single substance.