title: [Alpha-glucosidase inhibitory active constituents contained in nutshell of Trapa acornis].
abstract: OBJECTIVE
  To study chemical constituents in nutshell of Trapa acornis and in vitro inhibitory activity against alpha-glucosidase.
  
  
  METHODS
  EtOAC and n-butanol extractive fractions were separated by chromatography and their structures were identified by multiple spectroscopic techniques.
  
  
  RESULTS
  Nine compounds were separated, they were 4,23,24-trimethylcholest-22-en-3-ol (1), stigmasterol (2), alpha-amyrin (3), (+)-nyasol (4), oleanolic acid (5), ursolic acid (6), hederagenin (7), 3,23-dihydroxy-12-ursen-28-oic acid (8) and beta-daucosterol (9). Total extracts from T. acornis nutshells, petroleum ether fractions, acetic ether fractions and normal butanol fractions showed inhibitory activity against alpha-glucosidase. Compound 5 (IC50 2.88 mg x L(-1)) and 6 (IC50 4.42 mg L(-1)) showed stronger inhibitory activity against alpha-glucosidase.
  
  
  CONCLUSIONS
  All compounds except compound 2 were separated from the genus for the first time, and compound 1-9 were separated from this plant for the first time.
authors.affiliation: Institute of Chinese Materia Medica, Henan University, Kaifeng 475004, China.
authors.forename: Baiquan
authors.initials: B
authors.lastname: Chen
authors.forename: Qian
authors.initials: Q
authors.lastname: Zhang
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.forename: Huan
authors.initials: H
authors.lastname: Huang
authors.forename: Wenyi
authors.initials: W
authors.lastname: Kang
mesh_terms: D004791:Enzyme Inhibitors / Q000737:chemistry*; D065089:Glycoside Hydrolase Inhibitors; D029561:Lythraceae / Q000737:chemistry*
chemical_list: D004791:Enzyme Inhibitors; D065089:Glycoside Hydrolase Inhibitors