title: Flavonoids from silkworm droppings and their promotional activities on heme oxygenase-1.
abstract: A new flavane glucoside, 7,2'-dihydroxy-8-hydroxyethyl-4'-methoxyflavane-2'-O-β-d-glucopyranoside (3), along with three known flavonoids, 7,2'-dihydroxy-8-prenyl-4'-methoxyflavane (1), euchrenone a(7) (2), and 7,2'-dihydroxy-8-prenyl-4'-methoxy-2'-O-β-d-glucopyranosylflavane (4), was isolated from silkworm droppings. The structures of the compounds were elucidated on the basis of 1D and 2D NMR spectroscopic analyses and optical rotational characteristics. The compounds isolated from silkworm droppings were evaluated for their effects on heme oxygenase-1 (HO-1) activity. Compounds 1 and 3 increased the expression of HO-1 in HepG2 cells. HO-1 is an antioxidant enzyme that catabolizes heme to carbon monoxide, free iron, and biliverdin, all of which are involved in the suppression of inflammatory mediators.
authors.affiliation: College of Life Sciences & Plant Metabolism Research Center, Kyung Hee University, Yongin, South Korea.
authors.forename: Ji-Hae
authors.initials: JH
authors.lastname: Park
authors.forename: Dae-Young
authors.initials: DY
authors.lastname: Lee
authors.forename: Pyeong
authors.initials: P
authors.lastname: Yun
authors.forename: Seung-Woo
authors.initials: SW
authors.lastname: Yeon
authors.forename: Jong Hee
authors.initials: JH
authors.lastname: Ko
authors.forename: Yong-Soon
authors.initials: YS
authors.lastname: Kim
authors.forename: Nam-In
authors.initials: NI
authors.lastname: Baek
mesh_terms: D000818:Animals; D001664:Biliverdine / Q000378:metabolism; D012831:Bombyx / Q000378:metabolism*; D005243:Feces / Q000737:chemistry; D005419:Flavonoids / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D005960:Glucosides / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D051547:Heme Oxygenase-1 / Q000187:drug effects*; D056945:Hep G2 Cells; D006801:Humans
chemical_list: C558754:7,2'-dihydroxy-8-hydroxyethyl-4'-methoxyflavane-2'-O-beta-D-glucopyranoside; D005419:Flavonoids; D005960:Glucosides; D051547:Heme Oxygenase-1; D001664:Biliverdine