Differential effects of biologically and chemically synthesized copper oxide nanoparticles on artemisinin biosynthesis gene expression in Artemisia absinthium

Artemisinin is an effective antimalarial compound produced by Artemisia absinthium. Due to its low natural yields, it is crucial to investigate novel strategies to enhance biosynthesis of artemisinin. The impact of copper oxide nanoparticles (CuO NPs) on the expression of important genes involved in the biosynthesis of artemisinin was examined in this work. CuO NPs were synthesized using both green microwave irradiation and conventional wet chemical methods. Application of a variety of techniques, including XRD, DLS, FESEM, EDX, and FTIR confirmed the proper synthesis of CuO NPs. Nodal segments of A. absinthium were treated with CuO NPs at 2 and 4 ppm in MS medium and gene expression was analyzed using qRT-PCR. The results showed significant increases in key biosynthetic genes, including FDS, ADS, CYP71AV1, DBR2, and ALDH1. Specifically, a high level of expression of several transcripts associated with ADS, CYP71AV1, and DBR2 was observed in the cultures treated with 4 ppm of green synthesized CuO NPs (with 2.03-, 2.00-, and 1.83-fold increases, respectively) and 2 ppm of chemically synthesized CuO NPs (with 2.35-, 1.86-, and 2.34-fold increases, respectively), in comparison with the control. Additionally, there was only a slight increase in RED1, a gene that redirects metabolic flow away from artemisinin production. It can be concluded that CuO NPs, particularly those synthesized with green method, can be considered as potent nano-elicitors, enhancing the biosynthesis of artemisinin by modifying gene expression. This study demonstrates how nanotechnology can be used to increase pharmaceutical compound production of medicinal plants in a sustainable manner.