Ultrasound-Assisted Water Extraction of Mastocarpus stellatus Carrageenan with Adequate Mechanical and Antiproliferative Properties

• Published in: Marine drugs Vol. 19; no. 5; p. 280
• Main Authors: Torres, Maria Dolores, Flórez-Fernández, Noelia, Dominguez, Herminia
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 19.05.2021; MDPI
• Subjects: Amplitude; Amplitudes; Antioxidants; antiproliferative; biopolymer; Biopolymers; Box–Behnken design; Carrageenan; Carrageenans; Enzymes; Experiments; Gallic acid; hybrid carrageenan; Hydrogels; Mastocarpus stellatus; Mechanical properties; Molecular weight; Phenolic compounds; Phenols; Protein composition; Proteins; Rheological properties; Rheology; Sulfates; Ultrasonic imaging; Ultrasound; Variables; Viscoelasticity; Vitamin E; Yield
• ISSN: 1660-3397; 1660-3397
• DOI: 10.3390/md19050280

Ultrasound-assisted water extraction was optimized to recover gelling biopolymers and antioxidant compounds from Mastocarpus stellatus. A set of experiments following a Box–Behnken design was proposed to study the influence of extraction time, solid liquid ratio, and ultrasound amplitude on the yield, sulfate content, and thermo-rheological properties (viscoelasticity and gelling temperature) of the carrageenan fraction, as well as the composition (protein and phenolic content) and antiradical capacity of the soluble extracts. Operating at 80 °C and 80 kHz, the models predicted a compromise optimum extraction conditions at ~35 min, solid liquid ratio of ~2 g/100 g, and ultrasound amplitude of ~79%. Under these conditions, 40.3% carrageenan yield was attained and this product presented 46% sulfate and good mechanical properties, a viscoelastic modulus of 741.4 Pa, with the lowest gelling temperatures of 39.4 °C. The carrageenans also exhibited promising antiproliferative properties on selected human cancer cellular lines, A-549, A-2780, HeLa 229, and HT-29 with EC50 under 51.9 μg/mL. The dried soluble extract contained 20.4 mg protein/g, 11.3 mg gallic acid eq/g, and the antiradical potency was equivalent to 59 mg Trolox/g.