Optimisation of fermentation conditions for the production of a novel GABA-benzodiazepine receptor agonist byAcremonium strictum

The production of XR368, a novel GABA-benzodiazepine receptor agonist, has been optimised through manipulation of the medium composition and fermentation conditions leading to an increase in product titre from 1 to 100 mg L^–1. Key steps in the optimisation process were the selection of carbon and nitrogen sources, and the optimisation of the CN ratio and medium concentration. Furthermore, downstream processing has been facilitated through the introduction of a detergent treatment step which results in the release of over 90% of the desired product into the extracellular environment, avoiding the need to process both biomass and liquor fractions.