title: Alpha-glucosidase inhibition of natural curcuminoids and curcumin analogs.
abstract: Natural curcumin (1), demethoxycurcumin (2) and bisdemethoxycurcumin (3) isolated from Curcuma longa (turmeric), and synthetic curcumin analogs (A(1-7), B(1-7), C(1-6) and D(1-7)) were evaluated in vitro for the alpha-glucosidase inhibitory activity via UV and circular dichroism (CD) spectroscopy. The results indicated that natural curcuminoid compound 3 showed a remarkable inhibitory effect with IC(50) of 23.0 microM, and the synthetic compounds A(2), B(2), C(2) and D(2) showed potent inhibitory effects with IC(50) of 2.8, 2.6, 1.6 and 8.2 microM, respectively. Kinetic study exhibited that the mechanism of alpha-glucosidase inhibition of both 3 and C(2) was non-competitive. The structure activity relationship revealed that the ortho dihydroxyl groups could form a more tight interaction with alpha-glucosidase to exert more potential inhibitory activities.
authors.affiliation: School of Chemistry and Chemical Engineering, Sun Yat-Sen University, Guangzhou 510275, China.
authors.forename: Zhi-yun
authors.initials: ZY
authors.lastname: Du
authors.forename: Rong-rong
authors.initials: RR
authors.lastname: Liu
authors.forename: Wei-yan
authors.initials: WY
authors.lastname: Shao
authors.forename: Xue-pu
authors.initials: XP
authors.lastname: Mao
authors.forename: Lin
authors.initials: L
authors.lastname: Ma
authors.forename: Lian-quan
authors.initials: LQ
authors.lastname: Gu
authors.forename: Zhi-shu
authors.initials: ZS
authors.lastname: Huang
authors.forename: Albert S C
authors.initials: AS
authors.lastname: Chan
mesh_terms: D000818:Animals; D030024:Curcuma / Q000737:chemistry*; D003474:Curcumin / Q000031:analogs & derivatives / Q000138:chemical synthesis / Q000302:isolation & purification / Q000494:pharmacology*; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D065089:Glycoside Hydrolase Inhibitors; D020128:Inhibitory Concentration 50; D007700:Kinetics; D013329:Structure-Activity Relationship
chemical_list: D004791:Enzyme Inhibitors; D065089:Glycoside Hydrolase Inhibitors; D003474:Curcumin