Research On Chemical Composition And Biological Activity Of Radix Paeoniae Alba

Radix Paeoniae Alba, derived from the dried roots of Paeonia lactiflora Pall. in Paeonia genus Ranunculaceae family, is widely distributed in Zhejiang, Anhui, Sichuan province.In our bioactivity-guided isolation of the chemical constituents of P. lactiflora,20 compounds were obtained from the EtOAc soluble parts of the 60% ethanol extract of the dried roots of this plant through various chromatographic techniques. Their structures were elucidated on the basis of physiochemical property and spectroscopic analysis. The 20 compounds from P. lactiflora are 4’-O-benzoylpaeoniflorin (1)*,4-O-galloylalbiflorin (2)*, paeoniflorin (3), acetylpaeoniflorin (4), benzoylpaeoniflorin (5), benzoyloxypaeoniflorin (6),4-O-methyl-benzoylpaeoniflorin (7), albiflorin (8), galloylalbiflorin (9), benzoylalbiflorin (10), lactiflorin (11), 1-O-β-D-glucopyranosyl-8-O-benzoylpaeonisuffrone (12),6’-O-benzoylpaeonidanin (13), naringenin-7-O-β-D-glucopyranoside (14)#, (+)-catechin (15), benzoic acid (16), gallic acid (17), methyl gallate (18), ethyl gallate (19), 1,2,3,4,6-pentagalloylglucose (20). Among them, compounds 1 and 2 are new compounds, and compound 14 was isolated from the Paeonia genus for the first time.The fingerprint chromatograms of the 60% ethanol extract and EtOAc soluble parts of P. lactiflora have been established using DAD-HPLC. Above 80% of the peak areas in the chromatogram have been identified by comparing with the pure compounds (2,3,5,8-10,15-20) isolated from the plant in each chromatogram.The immunomodulatory activity of several compounds was evaluated. Among the 18 tested compounds,4 compounds were found to promote the proliferation of T lymphocytes of mice, in which compound 20 (1,2,3,4,6-pentagalloylglucose) showed promotion activity significantly. Further test results showed that the 4 compounds had activity within 5～100μM, but there were no obvious dose-effect relationships.All the compounds, except compounds 4 and 6, were evaluated for anti-inflammatory activity.20 (1,2,3,4,6-pentagalloylglucose) was found to inhibit NO release of rat peritoneal macrophages in 100μM, but there were no obvious dose-effect relationships within 1～100μM.18 compounds were evaluated for inhibitory activity against tyrosinase. The results showed that compound 20 (1,2,3,4,6-pentagalloylglucose) possessed strong inhibitory activity within 1～100μM, and there is obvious dose-effect relationship. The half inhibition concentration is 28.03μM.