Analysis of peramine in fungal endophyte-infected grasses by reversed-phase thin-layer chromatography

Abstract

The presence of the fungal endophyte Acremonium lolii in perennial ryegrass (Lolium perenne) has been linked to resistance of infected plants to attack by the Argentine stem weevil (Listronotus honariensis). Production in the infected plants of the alkaloid peramine, a feeding deterrent to adult weevils, is thought to be largely responsible for the resistance’. Isolation and identification of peramine was first reported by Rowan and coworkers’,*, but the method used was too time-consuming and difficult for use in routine analysis. Tapper et a1.3 recently reported an improved method for extraction, identification and measurement of peramine. Their procedure involved a two-stage extraction using methanolchloroform (1: 1, v/v); then hexaneewater (l:l, v/v) followed by cleanup of the extract on small ion-exchange columns. Peramine was detected on silica gel layers using Ehrlich’s reagent or quantified by a high-performance liquid chromatography (HPLC) procedure. We report here the development of a rapid and sensitive reversed-phase (RP) thin-layer chromatography (TLC) procedure for detection and quantitation of peramine in crude extracts of endophyte-infected grasses.