Optimization of enzyme-assisted ultrasound extraction of polysaccharides from wild sotol (Dasylirion wheeleri) plants using response surface methodology

• The effects of key parameters on the EAUE of sotol polysaccharides were investigated. • Ultrasound power, temperature, and enzyme concentration were identified as significant factors. • A second-order model that adequately described all responses was proposed. • The optimal extraction conditions were determined and verified. • Enhanced sotol fructan extraction can be achieved through EAUE. Sotol plants are rich in fructans, which hold strong potential as functional ingredients in the food industry. However, their yield and quality are influenced by the extraction methods and conditions employed. In this study, enzyme-assisted ultrasound extraction (EAUE) of polysaccharides from sotol ( Dasylirion wheeleri ) was optimized under varying ultrasound powers (UP), temperatures (T), and enzyme concentrations (EC) using a central composite design. Conventional thermal extraction at 85 °C was used as the control. The sotol polysaccharide extraction yield (SPEY), reducing sugars (RS), total fructan content (FRU), glucose and fructose contents, and the average degree of polymerization (DP n ) were evaluated in the obtained sotol extracts. The variables UP, T, and EC had significant effects, and a second-order model that adequately described all the responses was proposed. The highest fits (> 99%) were observed for RS and the glucose and fructose contents, followed by SPEY, FRU, and DP n (>86%). The optimal extraction conditions were a UP of 43.75 W, a T of 44.15°C, and an EC of 334 U/g of sotol powder, resulting in a FRU of 50.67 g/100 g dw, SPEY of 75.3%, RS of 20.11 g/100 g dw, glucose content of 9.67 g/100 g dw, fructose content of 3.02 g/100 g dw, and a DP n of 1.23. These results demonstrate that the extraction of sotol fructans can be enhanced using EAUE compared with a hot-water process. Low DP n fructans obtained by EAUE can be used as functional ingredients in the formulation of various food products, providing low viscosity and prebiotic effects.