RESUMEN
Objective: To study the chemical constituents in the whole herb of Lycopodium japonicum. Methods: The constituents were isolated and purified by silica gel and semi-preparative HPLC, and their structures were elucidated by means of physicochemical properties and spectroscopic analysis. All the isolated compounds were evaluated using relevant in vitro anti-inflammatory assay against LPS-induced NO releases. Results: Nineteen compounds were isolated from the whole herb of L. japonicum, and identified as lycoposerramine-M N-oxide (1), acetyllycoposerramine-M (2), lycopodine (3), lycoposerramine-M (4), miyoshianine-C (5), 12-epilycodoline N-oxide (6), gnidioidine (7), lycoposerramine-K (8), lucidioline (9), 4α-hydroxyanhydrolycodoline (10), flabelline (11), hydroxypropyllycodine (12), lycodine (13), des-N-methyl-α-obscurine (14), α-obscurine (15), des-N-methyl-β-obscurine (16), lycoflexine (17), lycoflexine N-oxide (18), and fawcettidine (19). Compound 5 and 18 could inhibit the release of nitric oxide (NO) in the RAW264.7 cell line stimulated by lipopolysaccaride. The IC50 values of 5 and 18 are 31.82 and 40.69 μmol/L, respectively. Conclusion: Compound 1 is a new compound, named lycoposerramine-M N-oxide, compounds 2, 6, 11, 12, 16, 18, and 19 are isolated from this plant for the first time. Compounds 5 and 18 exhibit the potent inhibitory activity.