Plant metabolism of xenobiotics. Comparison of the metabolism of 3.4-dichloroaniline in soybean excised leaves and soybean cell suspension cultures

Abstract

Excised leaves and cell suspension cultures of soybean (Glycine max L.) were incubated with [UL-14C]-3, 4-dichloroaniline. The compound was almost completely metabolized after 48 h in both systems; it was apparent that the major detoxification pathways present in the excised leaves were also present in the cultured cells. Besides considerable amounts of insoluble residues, the N-glucosyl and the N-malonyl conjugates of 3, 4-dichloroaniline, and a yet unknown metabolite was formed in the excised leaves; tentatively the latter was identified with the 6'-0-malonylester of N-glucosyl-3, 4-dichloroaniline. The cell suspension cultures produced predominantly the N-malonyl conjugate, besides negligible amounts of the N-glucosyl conjugate, and insoluble residues; the majority of the N-malonyl compound was excreted into the medium. It was shown, that the metabolism of 3, 4-dichloroaniline in excised leaves and cell suspension cultures of soybean was directed towards different end products: the excised leaves were able to make extensive use of cell wall structures as a deposit for xenobiotic bound residues, resembling plants in this respect; lack of these structures in the cultured soybean cells resulted in a soluble end product, namely the N-malonyl conjugate. © 1992, Walter de Gruyter. All rights reserved.