Résumé
Objective: To investigate the chemical constituents from Juniperus convallium, as well as their anticomplementary and antioxidant activities. Methods: The constituents were isolated and purified by column chromatography over silica gel, Sephadex LH-20, ODS-C18, and preparative HPLC. Their structures were identified by spectra analysis. The cell hemolysis assay was used to evaluate the anticomplementary activities and the targets through classical and alternative pathways. Also the anti-oxidant activities were tested by DPPH, ABTS and FRAP methods. Results: A total of 17 compounds were obtained from the ethyl acetate extract of J. convallium and identified as amentoflavone (1), cupressuflavone (2), cupressuflavone-4″’-O-β-D-glucosides (3), naringenin-7-O- glycoside (4), apigenin (5), tiliroside (6), quercetin 3-O-β-D-glucoside (7), quercetin-3-O-rhamnoside (8), hypolaetin-7-O-β-D- glucopyranoside (9), isomassonianoside B (10), (+)-isolariciresinol 2a-O-β-D-glucoside (11), (+)-isolarisiresinol 3a-O-β-D-glucopyranoside(12), cryptomeridiol (13), 3β-hydroxysandaracopimeric acid (14), (1R,3R,4aR,4bS,7R,10aR)-7-ethenyl-1,2,3,4,4a,4b,5,6,7,9,10,10a- dodecahydro-3-hydroxy-1,4a,7-trimethyl-1-phenanthrene methanol (15), 4-hydroxy-5-methyl-coumarin (16) and β-sitosterol (17). Compounds 1-15 and 17 showed anticomplementary activities in different degrees (CH50: 0.05-3.99 mmol/L, AP50: 0.58 -19.13 mmol/L). The flavonoids, especially the biflavonoids, are the important anticomplementary constituents in J. convallium. Further analysis of structure-activity relationship showed that phenolic hydroxyl and glycosidic groups influenced their anticomplementary activity. Only the flavonoids (1-3, 5-9) and lignans (10-12) showed different degrees of antioxidant activities due to their hydroxyl groups. Conclusion: All the 17 compounds are isolated from J. convallium for the first time. The flavonoids and lignans are the important anticomplementary and antioxidant constituents in J. convallium with a certain structure-acticity relationship. This study provides a good reference for further research on the pharmacological substance and quality control of J. convallium.