Biological Activity of Dhurrin and Other Compounds from Johnson Grass (Sorghum halepense)

Abstract

Johnson grass (Sorghum halepense L. Pers.), a severe weed pest in the southeastern United States, has been shown by several workers to release compounds toxic to higher plants. Here, several previously isolated phytotoxins and taxiphyllin, not previously found in Johnson grass, have been isolated from methanolic extracts of Johnson grass rhizomes. These compounds were active against tomato and radish seedling root growth and also inhibited growth of several of nine bacteria tested. Exudates from living rhizomes did not affect radish and tomato root growth but did affect bacterial growth and slowed germination of three of five crop species tested. A 13C NMR method is presented for distinguishing the epimers dhurrin and taxiphyllin which were found in Johnson grass rhizomes. © 1983, American Chemical Society. All rights reserved.