title: Hydrolysis of the potato glycoalkaloid alpha-chaconine by filamentous fungi.
abstract: Three strains of filamentous fungi have been isolated from potato sprouts to obtain an enzyme degrading the glycoalkaloids. All of the strains hydrolyzed alpha-chaconine and not alpha-solanine when grown on the sprouts. From strain HP341, identified as Plectosphaerella cucumerina, the enzyme hydrolyzing alpha-chaconine was purified on columns of DEAE-Toyopearl and Phenyl-Toyopearl. The partially purified enzyme hydrolyzed alpha-chaconine to beta1-chaconine but not to beta2- or gamma-chaconine, suggesting that the enzyme is a rhamnosidase specific for the hydrolysis of the rhamnose (C1-C4) glucose linkage in alpha-chaconine. Conversion of alpha-chaconine to beta1-chaconine may be the first step of detoxification for filamentous fungi to grow on potato sprouts that accumulated antifungal alpha-chaconine.
authors.affiliation: Department of Upland Agriculture Research, National Agricultural Research Center for Hokkaido Region, Memuro, Kasai, Hokkaido 082-0071, Japan. yujioda@affrc.go.jp
authors.forename: Yuji
authors.initials: Y
authors.lastname: Oda
authors.forename: Katsuichi
authors.initials: K
authors.lastname: Saito
authors.forename: Akiko
authors.initials: A
authors.lastname: Ohara-Takada
authors.forename: Motoyuki
authors.initials: M
authors.lastname: Mori