title: Isolation of cholinesterase-inhibiting flavonoids from Morus lhou.
abstract: Cholinesterases are key enzymes that play important roles in cholinergic transmission. Nine flavonoids displaying cholinesterase inhibitory activity were isolated from the root bark of Morus lhou L., a cultivated edible plant. The isolated compounds were identified as a new flavone (1), 5'-geranyl-5,7,2',4'-tetrahydroxyflavone (2), kuwanon U (3), kuwanon E (4), morusin (5), morusinol (6), cyclomorusin (7), neocyclomorusin (8), and kuwanon C (9). All compounds apart from compound 6 inhibited cholinesterase enzyme in a dose-dependent manner with K(i) values ranging between 3.1 and 37.5 μM and between 1.7 and 19.1 μM against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes, respectively. The new compound was charactierized as 5'-geranyl-4'-methoxy-5,7,2'-trihydroxyflavone (1). It showed the most potent inhibitory activity (K(i) = 3.1 μM for AChE, K(i) = 1.74 μM for BChE). Lineweaver-Burk and Dixon plots and their secondary replots indicated that flavones (5-9) with prenyl substitution on C-3 were noncompetitive inhibitors, whereas those unsubstituted (1-4) at C-3 were mixed inhibitors of both AChE and BChE. In conclusion, this is the first study to demonstrate that alkylated flavonoids of M. lhou have potent inhibitory activities against AChE and BChE.
authors: Division of Applied Life Science (BK21 program, IALS), Gyeongsang National University, Jinju, Republic of Korea.
authors: Ji Young
authors: JY
authors: Kim
authors: Woo Song
authors: WS
authors: Lee
authors: Young Soo
authors: YS
authors: Kim
authors: Marcus J
authors: MJ
authors: Curtis-Long
authors: Byong Won
authors: BW
authors: Lee
authors: Young Bae
authors: YB
authors: Ryu
authors: Ki Hun
authors: KH
authors: Park
mesh_terms: D002800:Cholinesterase Inhibitors / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D002802:Cholinesterases / Q000737:chemistry; D005419:Flavonoids / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D007700:Kinetics; D031625:Morus / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D018517:Plant Roots / Q000737:chemistry
chemical_list: D002800:Cholinesterase Inhibitors; D005419:Flavonoids; D010936:Plant Extracts; D002802:Cholinesterases