Chondrus crispus treated with ultrasound as a polysaccharides source with improved antitumoral potential

Ultrasound-assisted extraction was used to recover gelling biopolymers and antioxidant compounds from Chondrus crispus with improved biological potential. The optimal processing conditions were evaluated using a Box-Behnken design, and the impact on the biological and thermo-rheological properties of the carrageenan fraction and on the bioactive features of the soluble extracts were studied. The optimum extraction parameters were defined by extraction time of ~34.7 min; solid liquid ratio of ~2.1 g/100 g and ultrasound amplitude of ~79.0% with a maximum power of 1130 W. The dependent variables exhibited maximum carrageenan yields (44.3%) and viscoelastic modulus (925.9 Pa) with the lowest gelling temperatures (38.7 °C) as well as maximum content of the extract in protein (22.4 mg/g), gallic acid (13.4 mg/g) and Trolox equivalents antioxidant capacity (182.4 mg TEAC/g). Tested hybrid carrageenans exhibited promising biological activities (% of growth inhibition around 91% for four human cancer cellular lines: A549; A2780; HeLa 229; HT-29). •The proposed Box-Behnken design was useful to optimize ultrasound treatment of C. crispus.•The optimum conditions were 34.7 min extraction time, 2.1 g/100 g solid liquid ratio and 79.0% amplitude.•Solid liquid ratio and extraction time were the variables with higher contribution on the extracts features.•Optimum treatment involved rheologically suitable carrageenans without jeopardizing the antioxidant features.•Predicted features under the optimal conditions involved biopolymers with enhanced biological activities.