Microwave-Assisted Extraction of Polysaccharides From the Abelmoschus sagittifolius: Optimization, Structure, and Bioactivity

The aim of this study was to extract polysaccharides from Abelmoschus sagittifolius using the microwave-assisted extraction (MAE) method. Three independent variables, including extraction temperature, microwave power, and microwave time, were chosen for investigation through single-factor experiments. Response surface methodology (RSM) based on a Box-Behnken design (BBD) was utilized to optimize the extraction conditions. The study found that the optimal conditions for polysaccharide extraction were a temperature of 63 degrees C, a microwave power of 650 W, and a duration of 58 min. The polysaccharide yield under these conditions was 29.8 g/100 g, closely matching the experimental yield of 30.1 g/100 g. This yield was approximately 1.15 times higher than the yield achieved through conventional extraction methods (heat reflux extraction (HE) method). The study also demonstrated that polysaccharides extracted using the MAE method exhibited improved antioxidant capacity and enzyme inhibition and displayed significant inhibitory effects on HepG2 cells compared to the conventional extraction method. Moreover, the polysaccharides obtained from the optimized MAE process had a lower molecular weight and higher polydispersity than the HE method. These findings indicate that MAE is a promising, efficient, and environmentally friendly technology for extracting polysaccharides from A. sagittifolius.