later they may be used after being purified so as to improve the purity of nobiletin the purification of the extract can be achieved by for example silica gel chromatography using a suitable eluent as the eluent it is preferable to use for example a mixed solvent of a solvent such as ethyl acetate methanol isopropyl ether tetrahydrofuran benzene or xylene and a solvent such as hexane heptane chloroform or dichloroethane as described in the following the present example verified the activation of ppar u03b3 by nobiletin first cv 1 cells cultured cells derived from kidneys of male african green monkeys were inoculated on 24 well culture plates so as to be 0 2 u03bcg well and cultured at 37 u00b0 c in 5 co 2 for 24 hours as a medium dmem dulbecco 39 s modified eagle medium available from gibco containing 10 fbs fetal bovine serum and a 10 mg ml penicillin streptomycin solution was used next using the lipofectamine system invitrogen corporation pm hppar u03b3 and p4 u00d7 uasg tk luc were transfected into the cultured cv 1 cells the above noted pm hppar u03b3 was a vector for expressing fusion protein containing residues 1 147 of gal4 binding domain and residues 204 505 of human ppar u03b3 ligand binding domain and the above noted p4 u00d7 uasg tk luc was a reporter plasmid containing four copies of an upstream activating sequence uas for gal4 binding domain.