title: Antioxidant and α-Glucosidase Inhibitory Constituents from Hornstedtia Species of Malaysia.
abstract: Seven compounds were isolated from the n-hexane and chloroform extracts of the flowers and leaves of four Hornstedtia species and their structures were identified using spectroscopic techniques as 3,7,4'-trimethylkaempferol (1), 3,7-dimethylkaempferol (2), 7,4'-dimethylkaempferol (3), 3,5-dimethylkaempferol (4), 3-methylkaempferol (5), stigmast-4-en-3-one (6), and 6-hydroxy-stigmast-4-en-3-one (7). Compounds 1 to 7 were isolated from these species for the first time. They were assayed for free radical scavenging and α-glucosidase inhibition activities. The DPPH assay showed that 3-methylkaempferol (5) was the most potent antioxidant agent with an IC50 value 78.6 µM, followed by 7,4'-dimethylkaempferol (3) (IC50 = 86.1 µM). For α-glucosidase inhibition activity, 3-methylkaempferol (5) exhibited significant inhibitory activity with an IC50 value 21.0 µM. The present study revealed that Hornstedtia species have potential activities as antioxidant and α-glucosidase inhibitors.
authors.forename: Siti Ernieyanti
authors.initials: SE
authors.lastname: Hashim
authors.forename: Hasnah Mohd
authors.initials: HM
authors.lastname: Sirat
authors.forename: Khong Heng
authors.initials: KH
authors.lastname: Yen
authors.forename: Intan Safinar
authors.initials: IS
authors.lastname: Ismail
authors.forename: Siti Nurulhuda
authors.initials: SN
authors.lastname: Matsuki
mesh_terms: D000975:Antioxidants / Q000737:chemistry* / Q000494:pharmacology*; D001713:Biphenyl Compounds / Q000737:chemistry; D065089:Glycoside Hydrolase Inhibitors / Q000737:chemistry / Q000494:pharmacology*; D008296:Malaysia; D010851:Picrates / Q000737:chemistry; D018515:Plant Leaves / Q000737:chemistry; D030521:Zingiberaceae / Q000737:chemistry*; D000520:alpha-Glucosidases / Q000378:metabolism*
chemical_list: D000975:Antioxidants; D001713:Biphenyl Compounds; D065089:Glycoside Hydrolase Inhibitors; D010851:Picrates; C004931:1,1-diphenyl-2-picrylhydrazyl; D000520:alpha-Glucosidases