Process for the recovery of avermectin from a fermentation medium

摘要

In the whole broth extraction of avermectins, the pH of the whole broth is adjusted with mineral acid and the broth is then contacted with a solvent extractant so that the avermectin-active component is taken up by the solvent. The new avermectin-rich extractant is then processed through a solvent concentration step and the avermectin isolated by conventional crystallization. The extractant is then recycled with appropriate make-up to extract a subsequent batch of whole broth.