Presence of fatty acid synthase inhibitors in the rhizome of Alpinia officinarum hance.
The galangal (the rhizome of Alpinia officinarum, Hance) is popular in Asia as a traditional herbal medicine. The present study reports that the galangal extract (GE) can potently inhibit fatty-acid synthase (FAS, E.C.2.3.1.85). The inhibition consists of both reversible inhibition with an IC50 value of 1.73 microg dried GE/ml, and biphasic slow-binding inactivation. Subsequently the reversible inhibition and slow-binding inactivation to FAS were further studied. The inhibition of FAS by galangin, quercetin and kaempferol, which are the main flavonoids existing in the galangal, showed that quercetin and kaempferol had potent reversible inhibitory activity, but all three flavonoids had no obvious slow-binding inactivation. Analysis of the kinetic results led to the conclusion that the inhibitory mechanism of GE is totally different from that of some other previously reported inhibitors of FAS, such as cerulenin, EGCG (epigallocatechin gallate) and C75.
Li
Bing-Hui
BH
Department of Biology, Graduate School of Chinese Academy of Sciences, PO Box 3908, Beijing 100039, People's Republic of China.
Tian
Wei-Xi
WX
D032429:Alpinia / Q000737:chemistry*; D002384:Catalysis; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000494:pharmacology*; D004795:Enzyme Stability; D064429:Fatty Acid Synthases / Q000378:metabolism*; D005419:Flavonoids / Q000494:pharmacology*; D011485:Protein Binding; D011794:Quercetin / Q000494:pharmacology; D027343:Rhizome / Q000737:chemistry
D004791:Enzyme Inhibitors; D005419:Flavonoids; D011794:Quercetin; D064429:Fatty Acid Synthases