In vitro evaluation on the antiobesity effect of lignans from the flower buds of Magnolia denudata.

In the present study, an attempt has been made to isolate antiobesity components from crude extracts of the flower buds of Magnolia denudata by CH(2)Cl(2) and MeOH solvents. The crude extracts were partitioned into n-hexane, 85% aqueous MeOH, n-butanol, and water fractions. Their antiobesity effects were evaluated by measuring the effect on adipogenic differentiation using 3T3-L1 cells. Among the fractions, n-hexane and 85% aqueous MeOH fractions effectively reduced the lipid accumulation and the regulation of the adipogenic transcription factor. Both n-hexane and 85% aqueous MeOH fractions were further separated by diverse chromatographic methods to give four lignans (A-D). In comparative analysis, the presence of the lignans during adipogenic differentiation reduced the absorbance values of eluted Oil Red O solution in the order of potency C > D > B > A. Moreover, C and D effectively downregulated SREBP1, PPARγ, and C/EBPα.