Enrichment of a fraction toxic to guinea-pigs from Pachystigma pygmaeum (Schltr.) Robyns

Pachystigma pygmaeum is one of several species of rubiaceous plants which cause delayed heart failure among ruminants after their ingestion at relatively high doses. Using guinea-pigs for toxicity determinations, we were able to separate and enrich a toxic fraction from a fermentation extract of the plant material by countercurrent distribution. It contained virtually no potassium salts, passed through a 500 dalton selective membrane, exhibited lability under acid conditions and was toxic at 1 g/kg per os, with a delayed response of 3-4 days.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.Department of Agriculture