In this work, fourteen deep eutectic solvents (DES), four conventional solvents and four extraction techniques (ultrasonic-assisted, microwave-assisted, maceration and Soxhlet extractions) were tested for polysaccharide and antioxidant extraction from sweet and edible Larinus cocoon (Shakar tigal). Finally, Choline chloride-citric acid (DES) and ultrasonic-assisted extraction (UAE) were selected as the best solvent and technique for polysaccharides and antioxidants extraction. The Box-Behnken design (BBD) and response surface methodology (RSM) were used to optimize extraction variables (temperature, time, water content in choline chloride-citric acid, and liquid-to-solid ratio) in ultrasonic-assisted extraction. At optimum condition, total carbohydrate content and extraction yield were 5.32 mg Glu/gdw and 66.7%, respectively. Based on monosaccharide composition analysis, extracted polysaccharides had arabinose, xylose, glucose and galactose (molar ratio: 1:2.18:6.07:5.17). Presence of galactouronic acid (about 28.3%) was also confirmed by GC analysis. Based on TGA and DSC thermal analysis, extracted polysaccharides had the highest mass loss (about 50%) between temperatures of 250–370 °C. Antioxidant activity of extract was evaluated by different assays such as total phenolic (TPC) and total flavonoid content (TFC), DPPH assay, ferric-reducing antioxidant power (FRAP), trolox equivalent antioxidant capacity (TEAC) and reducing power assay (RPA).
