Influence of Extraction Methods on Antiplasmodial Potential of Bioactive Extracts from Artemisia annua L: Response Surface Methodology Approach for Microwave-Assisted Extraction

Abstract

This study focuses the eco-friendly extraction of medicinal plants and the optimal conditions for extracting bioactive ingredients from Artemisia annua L., which is regarded as a rich source of secondary metabolites with antiplasmodial potentials. The research specifically aimed to optimize the microwave-assisted extraction method for secondary metabolites from Artemisia annua L. using single-factor experiments. To enhance extraction yield and biological activities, Response Surface Methodology (RSM) was employed to develop predictive models for simulating and optimizing the extraction process. The antiplasmodial activity of the extract was evaluated. Ethanol (EtOH), a hydroethanolic mixture of EtOH:H₂O (70:30), and distilled water were used as extraction solvents. Among the various extraction methods investigated, microwave-assisted extraction (MAE) with a hydroethanolic solvent provided the highest extraction yield (13.35 %) and the best IC50 value of the in vitro antiplasmodial assay (2.67 µg/mL). Biological analyses confirmed that the extract exhibited strong antiplasmodial activity against Plasmodium falciparum strains in vitro. Under optimal microwave-assisted extraction conditions of 120 s for extraction time (X1), 80 % (v/v) for ethanol concentration (X2) and a solid-to-liquid ratio of 3.3:20 g/mL (X3); the extraction yield reached 13.35%, closely aligning with the model’s predicted value. This research work is of great significance as it has the propensity of contributing significantly to the management of malaria cases with attendant reduction in infant mortality rate in particular and general upgrading of healthcare in Africa.