Optimization of Natural Deep Eutectic Solvents' Extraction Process From Atractylodes macrocephala–Astragali Radix Using the Dual Mathematical Model and Its Activity Evaluation

Natural deep eutectic solvents (NADESs) have garnered significant attention for their application in the extraction of natural products. This study proposes a strategy to enhance the extraction efficiency of target compounds from the Atractylodes macrocephala Koidz-Astragali Radix (AM-AR) combination, and the crude extracts were employed for subsequent in vitro and in vivo investigations. The extraction efficiencies of nine NADESs and conventional solvents were compared for isolating calycosin 7-O-glucoside, ononin, quercetin, and atractylenolide III using high-performance liquid chromatography (HPLC) analysis. The extraction parameters were then optimized through response surface methodology (RSM) and genetic algorithm-back propagation neural network (GA-BPNN) models. In addition, the antioxidant activities were evaluated in vitro using assays such as 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) free radical scavenging, and ferric reducing antioxidant power (FRAP). An in vivo rat model of middle cerebral artery occlusion (MCAO) was utilized to assess the biological activities. Among the tested solvents, NADES-7 exhibited the highest extraction efficiency, achieving a comprehensive evaluation value of 0.173 and was selected for subsequent experiments. These findings indicate that NADESs can serve as promising alternative solvents for extracting natural products from traditional Chinese medicine (TCM).