Differences in the chemical profiles and biological activities of Paeonia lactiflora and Paeonia obovata.

Paeonia lactiflora and P. obovata are perennial herbs, each root of which has been consumed as a major oriental medicine, Paeoniae Radix and a famous folk medicine, Mountain Paeony Root, respectively. Although morphological studies have been performed comparing these two plants, there is insufficient scientific evidence that characterizes the differences in their chemical profiles and biological activities. Hence, the present study was undertaken to compare these two medicinal foods using a high-performance liquid chromatography-diode-array detector (HPLC-DAD) analysis and a gastric ulcer model in mice. HPLC analysis employed to assess the nine components revealed that P. lactiflora exhibited higher contents of phenolic compounds than P. obovata. Although a monoterpene glycoside, 6'-O-acetylpaeoniflorin was identified in P. obovata, it was not detected in P. lactiflora. Multivariate statistical analysis for HPLC data revealed that the orthogonal projections to latent structure-discriminant analysis is more appropriate than principal component analysis for differentiating the two groups. Moreover, the 50% methanol P. lactiflora extract (PL) was more effective against experimental gastric ulcer than P. obovata extract (PO) in the HCl/ethanol-induced ulcer model. In addition, PL displayed higher 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and lower nitric oxide production in a murine macrophage cell line, RAW 264.7, than PO. The DPPH radical scavenging activity of PL was as high as that of the positive control, butylated hydroxytoluene, at a concentration of 25 μg/mL.