title: Allergy-preventive effects of Hibiscus mutabilis 'versicolor' and a novel allergy-preventive flavonoid glycoside.
abstract: Allergy-preventive activity was demonstrated for the MeOH extract (HM) of the petals of Hibiscus mutabilis L. 'versicolor' MAKINO in a continuing search for allergy-preventive substances from natural sources, using the in vivo assay method. This assay system uses monitoring of a decrease in the blood flow at the tail vein of mice subjected to hen egg-white lysozyme (HEL) sensitization. By bioassay-directed fractionation, a new flavonol triglycoside, quercetin 3-O-[beta-D-xylopyranosyl(1-->2)-alpha-L-rhamnopyranosyl(1-->6)]-beta-D-galactopyranoside (1: mutabiloside), was isolated, together with four known flavonols identified as quercetin 3-O-[beta-D-xylopyranosyl(1-->2)]-beta-D-galactopyranoside (2) and kaempferol 3-O-[beta-D-xylopyranosyl(1-->2)]-beta-D-galactopyranoside (3), quercetin (4) and hyperoside (5). The structure of the new flavonol 1 was elucidated by spectroscopic methods. Among these flavonol derivatives, compounds 1 and 2 showed significant allergy-preventive effects.
authors.affiliation: School of Pharmacy and Pharmaceutical Sciences, Mukogawa Women's University, Japan.
authors.forename: Emiko
authors.initials: E
authors.lastname: Iwaoka
authors.forename: Hisae
authors.initials: H
authors.lastname: Oku
authors.forename: Yumi
authors.initials: Y
authors.lastname: Takahashi
authors.forename: Kyoko
authors.initials: K
authors.lastname: Ishiguro
mesh_terms: D000818:Animals; D018926:Anti-Allergic Agents / Q000302:isolation & purification / Q000494:pharmacology*; D005419:Flavonoids / Q000302:isolation & purification / Q000494:pharmacology*; D006027:Glycosides / Q000302:isolation & purification / Q000494:pharmacology*; D031584:Hibiscus / Q000737:chemistry*; D008297:Male; D051379:Mice; D009113:Muramidase / Q000276:immunology; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology; D010974:Platelet Aggregation / Q000187:drug effects; D012039:Regional Blood Flow / Q000187:drug effects; D013623:Tail / Q000098:blood supply
chemical_list: D018926:Anti-Allergic Agents; D005419:Flavonoids; D006027:Glycosides; D010936:Plant Extracts; C540145:quercetin 3-O-(beta-D-xylopyranosyl(1-2)-alpha-L-rhamnopyranosyl(1-6))-beta-D-galactopyranoside; C421864:hen egg lysozyme; D009113:Muramidase