Submitted to: Preparative Biochemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/15/1999
Publication Date: N/A
Interpretive Summary: The Colorado potato beetle is a major pest of potato, both in the United States and worldwide. Leptine glycoalkaloids are natural deterrents to the Colorado potato beetle (CPB), found only in the foliage of the wild potato species Solanum chacoense. In order to assess more accurately the effects which Leptine has on the CPB, it is advantageous to feet it to the CPB in artificial diet studies. In this paper we describe a technique for extracting and partially purifying quantities of leptines, suitable for use in insect diet studies. This research will benefit potato growers and potato physiologists.
Technical Abstract: Leptine I, a glycoalkaloid only known to occur in the foliage of the wild potato species Solanum chacoense (Bitt.), may be a potent feeding deterrent to the economically serious insect pest, the Colorado potato beetle (Leptinotarsa decemlineata Say). In order to demonstrate, systematically, the effectiveness of leptine I, incorporation into synthetic beetle diet trials is necessary. We describe a preparative procedure for the partial purification of leptine I by a series of steps, starting with a solid-phase C-18 extraction, followed by sequential silica gel chromatography, and finally reversed-phase preparative HPLC. This preparation yields a white powder, containing leptine I as the sole glycoalkaloid, with an overall purity of greater than 65%.