Purification of artemisinin precursor amorphadiene from microbial metabolites containing isomeride farnesene: Solid-Pd chemocatalysis of farnesene to squalene with high boiling point

Abstract

Due to complex chemical mechanism of sesquiterpene synthases, amorpha-4, 11-diene (AD) from microbial fermentation contained isomeride β-farnesene (FA) with similar boiling point. For purifying AD, FA was converted to biofuel-valued squalene (SQ) with high boiling point using solid Pd catalysts. (NHT)OS-Pd catalysts resulted in FA conversion of >99.9% and SQ selectivity of >99.0% at 80 °C for 5 h. Moreover, this catalyst exhibited great stability and recycling performance. When (NHT)OS-Pd was applied to AD mixture, almost FA was converted to SQ and AD remained in the pre-reaction state. As SQ had a higher boiling point, AD was easily distilled out.