Application of novel HPLC method to the analysis of regional and seasonal variation of the active compounds in Paeonia lactiflora

Alcohol extracts of the dried root of paeony (Paeonia lactiflora), an Oriental medicinal herb, have been reported to contain cardiovascular protective monoterpene glycosides such as paeoniflorin and albiflorin. To analyze these compounds, a novel HPLC method with good precision was developed by a gradient elution making use of Inertsil ODS-3 column and acetonitrile–H2O as the eluent. At the optimum analytical condition, albiflorin and paeoniflorin were resolved well with the retention times of 14.30 and 17.74 min, respectively. By applying this method, the contents of paeoniflorin and albiflorin in 12 regional samples of paeony root were compared. The contents of these compounds in the seasonal samples from different parts of 4 year-grown paeony were also analyzed, with the highest values in the root sample of June, which was expected to be applicable to a cultivation management for producing paeony root with good functional activity.