Encapsulation of phlorotannins from edible brown seaweed in chitosan: Effect of fortification on bioactivity and stability in functional foods.

Phlorotannins are a family of proven therapeutic agents. However, low stability disturbs their full bioactivity expression in the human body. Hence, this study focused on preserving their vitality through encapsulation. Phlorotannins isolated from Sargassum ilicifolium were encapsulated in the chitosan-tripolyphosphate carrier. Their storage stability, processing stability, and bioactivity retention upon in vitro digestion were determined. Results revealed the highest total phlorotannin content (TPC) of 854.38 ± 48 mg Phloroglucinol Equivalence/g in the semi-purified ethyl acetate fraction while the NMR spectrum and the LCMS profile revealed the isolation of phlorotannins in it. Storage at -18℃ and 4℃ temperatures preserved thrice both the encapsulated and non-encapsulated phlorotannins than ambient conditions. Encapsulated compound reported 56.4% of TPC retention at 175 ℃ processing temperature. Fermented fraction of encapsulated form showed significantly higher (p < 0.05) antioxidant activities and TPC (0.23 ± 0.03 mg/mL) suggesting the potential for targeted delivery of phlorotannins to their absorption sites through encapsulation.