Secoiridoid Glucosides from Fraxinus Excelsior with Effects on LPS-Induced Nitrite Production in RAW 264.7 Macrophages and Human Cancer Cell Lines

Abstract

Nine secoiridoid glucosides, excelside A (1) and excelside B (2), nuzhenide (3), GI3 (4), GI5 (5), ligstroside (6), oleoside-11-methyl ester (7), oleoside dimethyl ester (8), 1′′′-O-β-D-glucosylformoside (9), and one phenylethanoid, salidroside (10), were isolated from the seeds of Fraxinus excelsior. The structures were established on the basis of NMR spectroscopic methods supported by MS or HRMS. HPLC method and a calibration curve was constructed for analysis the constituents of the extract. All isolated compounds were tested for cytotoxicity in human cancer cell lines (Hep G2, COLO 205, and HL-60) and anti-inflammatory activities in LPS-treated RAW264.7 macrophage cells. Among them, the water extract 11, and the compounds 5, 8, 9, 10, and 4 were modestly active to inhibit nitrite production in macrophages, followed by compounds 3, 2, 1, 6, and 7. Compound 4 was slightly effective as an anti-proliferative agent in HL-60 cells with IC50 of 82.0 μM. There was no cytotoxicity observed for any compounds except for 4 and the extract in these cells.