Inhibitory Effects of Constituents from the Aerial Parts of Rosmarinus officinalis L. on Triglyceride Accumulation.

Sixteen flavonoids (1-16) including two new ones, named officinoflavonosides A (1) and B (2) were obtained from the aerial parts of Rosmarinus officinalis. Among the known ones, 6, 10, and 13 were isolated from the rosmarinus genus for the first time. Their structures were elucidated by chemical and spectroscopic methods. Moreover, the effects on sodium oleate-induced triglyceride accumulation (TG) in HepG2 cells of the above-mentioned compounds and 16 other isolates (17-32) reported previously to have been obtained in the plant were analyzed. Results show that eight kinds of flavonoids (compounds 1, 2, 3, 6-9 and 11) and seven kinds of other known isolates (compounds 17-20, 23, 26 and 31) possessed significant inhibitory effects on intracellular TG content in HepG2 cells. Among them, the activities of compounds 1 and 20 were comparable to that of orlistat, which suggested that these compounds in this plant might be involved in lipid metabolism.