title: Polyhydroxylated alkaloids isolated from mulberry trees (Morusalba L.) and silkworms (Bombyx mori L.).
abstract: New polyhydroxylated alkaloids, (2R,3R,4R)-2-hydroxymethyl-3,4-dihydroxypyrrolidine-N-propionamide from the root bark of Morus alba L., and 4-O-alpha-D-galactopyranosyl-calystegine B(2) and 3 beta,6 beta-dihydroxynortropane from the fruits, were isolated by column chromatography using a variety of ion-exchange resins. Fifteen other polyhydroxylated alkaloids were also isolated. 1-Deoxynojirimycin, a potent alpha-glucosidase inhibitor, was concentrated 2.7-fold by silkworms feeding on mulberry leaves. Some alkaloids contained in mulberry leaves were potent inhibitors of mammalian digestive glycosidases but not inhibitors of silkworm midgut glycosidases, suggesting that the silkworm has enzymes specially adapted to enable it to feed on mulberry leaves. The possibility of preventing the onset of diabetes and obesity using natural dietary supplements containing 1-deoxynojirimycin and other alpha-glucosidase inhibitors in high concentration is of great potential interest.
authors.affiliation: Faculty of Pharmaceutical Sciences, Hokuriku University, Ho-3 Kanagawa-machi, Kanazawa 920-1181, Japan. naoki22@po.incl.ne.jp
authors.forename: N
authors.initials: N
authors.lastname: Asano
authors.forename: T
authors.initials: T
authors.lastname: Yamashita
authors.forename: K
authors.initials: K
authors.lastname: Yasuda
authors.forename: K
authors.initials: K
authors.lastname: Ikeda
authors.forename: H
authors.initials: H
authors.lastname: Kizu
authors.forename: Y
authors.initials: Y
authors.lastname: Kameda
authors.forename: A
authors.initials: A
authors.lastname: Kato
authors.forename: R J
authors.initials: RJ
authors.lastname: Nash
authors.forename: H S
authors.initials: HS
authors.lastname: Lee
authors.forename: K S
authors.initials: KS
authors.lastname: Ryu
mesh_terms: D000470:Alkaloids / Q000302:isolation & purification*; D000818:Animals; D012831:Bombyx / Q000737:chemistry* / Q000201:enzymology; D002852:Chromatography, Ion Exchange; D003920:Diabetes Mellitus / Q000188:drug therapy; D006026:Glycoside Hydrolases / Q000037:antagonists & inhibitors* / Q000378:metabolism; D006801:Humans; D006900:Hydroxylation; D008517:Phytotherapy; D018515:Plant Leaves / Q000737:chemistry* / Q000378:metabolism; D010946:Plants, Medicinal / Q000627:therapeutic use
chemical_list: D000470:Alkaloids; D006026:Glycoside Hydrolases