Response surface optimization of mucilage aqueous extraction from flixweed (Descurainia sophia) seeds

• The mucilage extraction from Descurainia sophia seeds was optimized by RSM.
• A mucilage yield of 10.45% was obtained under the optimum conditions.
• The extracted mucilage had a high scavenging potential against DPPH free radical.

The effects of four factors of pH (4–8), temperature (50–95 °C), weed–seed ratio (W/S, 15–45), and time (1–4 h) on the yield of mucilage extraction of Descurainia sophia seeds were investigated using response surface methodology-Box-Behnken design (RSM-BBD). Results showed that a second-order model for the studied response was adequately fitted with a coefficient of determination of 98.7% (p < 0.0001). The optimum conditions to achieve the highest yield (10.45%) were extraction time of 2.9 h, extraction temperature of 94.32 °C, pH of 7.55 and the W/S ratio of 44.2. The extracted mucilage at the optimal point effectively scavenged DPPH free radical, and more concentrations of this polysaccharide indicated potent antioxidant activity in a dose-dependent manner.