An oxidatively stressful situation: a case of Artemisia annua L. Issue 1 (2nd January 2020) - Kam, Melissa Yit Yee
ABSTRACT: Artemisinin (ART) is an antimalarial compound that possesses a variety of novel biological activities. Due to the low abundance of ART in natural sources, agricultural supply has been erratic, and prices are highly volatile. While heterologous biosynthesis and semi-synthesis are advantageous in certain aspects, these approaches remained disadvantageous in terms of productivity and cost-effectiveness. Therefore, further improvement in ART production calls for approaches that should supplement the agricultural production gap, while reducing production costs and stabilising supply. The present review offers a discussion on the elicitation of plants and/or in vitro cultures as an economically feasible yield enhancement strategy to address the global problem of access to affordable ART. Deemed critical for the manipulation of biosynthetic potential, the mechanism of ART biosynthesis is reviewed. It includes a discussion on the current biotechnological solutions to ART production, focusing on semi-synthesis and elicitation. A brief commentary on the possible aspects that influence elicitation efficiency and how oxidative stress modulates ART synthesis is also presented. Based on the critical analysis of current literature, a hypothesis is put forward to explain the possible involvement of enzymes in assisting the final non-enzymatic transformation step leading to ART formation. This review highlights the critical factors limiting the success of elicitor-induced modulation of ART metabolism, that will help inform strategies for future improvement of ART production. Additionally, new avenues for future research based on the proposed hypothesis will lead to exciting perspectives in this research area and continue to enhance our understanding of this intricate metabolic process.