Biochemical characterization, antioxidant and antiproliferative assays of functional salt derived from Gracilaria corticata: Effects of ultrasound and temperature regimes

Abstract

This study investigates the effects of sonication and temperature on the extraction and biological activities of oligosaccharide-rich salts derived from the red seaweed Gracilaria corticata. Time (0, 5, 10, and 15 min) and temperature (10, 20, 30, and 40 °C) were varied to assess their impact on yield, antioxidant activity, mineral composition, cytotoxicity, and potential anticancer activity in Chinese hamster ovary (CHO) and hepatocyte-derived carcinoma (Huh-7) cell lines. The highest yield (51.34 ± 2.21 %) was obtained at 10 °C with 10 min of sonication, while the highest antioxidant activity (1.09 ± 0.12 mg g⁻¹) was observed at 20 °C with 15 min of sonication. Mineral analysis showed that potassium was 64707.00 ± 53597.41 mg kg⁻¹ at 10°C, 0-minute, and iron at 144.86 ± 48.06 mg kg⁻¹ at 20°C, 0-minute. NMR analysis revealed the highest galactose content (46.16 ± 7.63 %) in the yield obtained at 20 °C with 0 min of sonication. FT-IR confirmed that temperature and sonication affected the rheological properties of agar. Biological assays showed anti-proliferative activity of 37.99 ± 8.70 % on Huh-7 and 38.59 ± 6.10 % on CHO cell lines (20°C, 0-minute), lowest wound healing 21.42 % and 26.49 % after 6 and 12 h (20°C, 0-minute). This is the first study that optimized temperature sonication enhances the yield and bioactivity of Gracilaria corticata salts, offering a scalable route to nutraceutical and pharmaceutical applications.