Immunological Activities of Components from Leaves of Liriodendron chinensis

ObjectivesTo investigate the anti-inflammatory components from the leaves of Liriodendron chinensis.MethodsThe 95% alcohol extract from the leaves of L. chinensis was subjected to column chromatography, and the structures of purified compounds were determined by spectral methods. The bioassay was performed through the inhibitory effects on the inflammatory cells activated by lipopolysaccharide (LPS).ResultsNine compounds were isolated, including octacosanoic acid (1), stearic acid (2), (2R)-2-hydroxy-N-[(2S,3S,4R,8E)-1,3,4-tri-hydroxyicos-8-en-2-yl]tetracosanamide (3), (2R)-2-hydroxy-N-[(2S,3S,4R,8E)-1-O-β-D-glucopyranosyloxy-3,4-dihydroxy-octadec-8-en-2-yl]eicosanamide (4), (2R)-2-hydroxy-N-[(2S,3S,4R,8E)-1-O-β-D-glucopyranosyloxy-3,4-dihydroxyoctadec-8-en-2-yl]hexadecanamide (5), dicentrinone (6), liriodenine (7), daucosterol (8), and liriodendritol (9) and among which five compounds could significantly lower the content of nitric oxide (NO) from peritoneal macrophages of rats induced by LPS and reduce the splenic lymphocyte proliferation in mice. This is the first report on the occurrence of ceramides and dicentrinone in the plants of Liriodendron Linn.ConclusionThe five compounds are likely to be anti-inflammatory compounds concerning to their pronounced inhibitory action on the activated inflammatory cells. This assessment might provide a basis for searching the potent active compounds used for the treatment of inflammation.