Conceptual Process Synthesis for Recovery of Natural Products from Plants: A Case Study of Artemisinin from Artemisia annua

Abstract

A systematic method of conceptual process synthesis for recovery of natural products from their biological sources is presented. This methodology divides the task into two major subtasks namely, isolation of target compound from a chemically complex solid matrix of biological source (crude extract) and purification of target compound(s) from the crude extract. Process analytical technology (PAT) is used in each step to understand the nature of material systems and separation characteristics of each separation method. In the present work, this methodology is applied to generate process flow sheet for recovery of artemisinin from the plant Artemisia annua (A. annua). The process flow sheet is evaluated on the basis of yield and purity of artemisinin obtained in bench scale experiments. Yields of artemisinin obtained in individual unit operations of maceration, flash column chromatography, and crystallization are 90.0%, 87.1% and 47.6%, respectively. Results showed that the crystallization step is dominant to the overall yield of the process which was 37.3%.