Park Ji-Hae, Lee Dae-Young, Yun Pyeong, Yeon Seung-Woo, Ko Jong Hee, Kim Yong-Soon, Baek Nam-In
College of Life Sciences & Plant Metabolism Research Center, Kyung Hee University, Yongin, South Korea.
J Asian Nat Prod Res. 2011 Apr;13(4):377-82. doi: 10.1080/10286020.2011.555331.
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.
