title: Acetylcholinesterase-inhibiting steroidal alkaloid from the sponge Corticium sp.
abstract: A new stigmastane-type steroidal alkaloid, 4-acetoxy-plakinamine B (1), was isolated from the Thai sponge Corticium sp. The compound was subjected to the acetylcholinesterase inhibitory activity determination to reveal a high inhibitory activity (IC(50) 3.75+/-1.69 microM). The kinetics of enzyme inhibition showed a decrease in V(max), whereas K(m) was increased, thus suggesting an unusual mixed-competitive mode of inhibition. Compound 1 is the first steroidal alkaloid bearing a stigmastane skeleton ever been reported to exhibit such good potency in the acetylcholinesterase inhibition bioassay.
authors.affiliation: Department of Pharmacognosy and Pharmaceutical Botany, Faculty of Pharmaceutical Sciences, Prince of Songkla University, Hat-Yai, Songkhla 90112, Thailand.
authors.forename: Roosanee
authors.initials: R
authors.lastname: Langjae
authors.forename: Somchai
authors.initials: S
authors.lastname: Bussarawit
authors.forename: Supreeya
authors.initials: S
authors.lastname: Yuenyongsawad
authors.forename: Kornkanok
authors.initials: K
authors.lastname: Ingkaninan
authors.forename: Anuchit
authors.initials: A
authors.lastname: Plubrukarn
mesh_terms: D000110:Acetylcholinesterase / Q000378:metabolism*; D000470:Alkaloids / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D000818:Animals; D002800:Cholinesterase Inhibitors / Q000302:isolation & purification / Q000494:pharmacology*; D011161:Porifera / Q000737:chemistry*
chemical_list: D000470:Alkaloids; D002800:Cholinesterase Inhibitors; D000110:Acetylcholinesterase