Evaluation of antioxidant potential of anthocyanin-rich hydro ethanol extract of Syzygium cumini fruit pulp in various in vitro models and in food supplement enriched with omega-3 fatty acids

Omega-3 fatty acids have immense health benefits but are highly susceptible to oxidation due to high degree of unsaturation in their molecular structure. Therefore, development of omega-3 fatty acids fortified stable functional food is a challenging task. The aim of the study was to evaluate antioxidant potential of anthocyanin-rich hydro ethanol extract of Syzygium cumini fruit pulp extract in various in vitro models and in omega-3 fatty acids enriched food supplement in bulk oil and oil-in-water emulsions model systems along with chemical analysis of the fruit pulp extract and evaluation of its cytotoxic potential, if any. The in vitro antioxidant potential was evaluated by DPPH radical scavenging, ABTS°+ decolorization and Fe2+ ion chelating methods. Antioxidant activity against oxidation of omega-3 fatty acids enriched food supplement in bulk oil and oil-in-water emulsions model systems was evaluated by monitoring primary oxidation, secondary oxidation and total oxidation of the omega-3 enriched oil using AOCS guidelines and iodometric method. Chemical analysis was performed by HR-LCMS analysis technique. Cytotoxic potential was evaluated by Allium cepa test. The test extract exhibited varying degrees of antioxidant activity in various in vitro models as well as against oxidation of omega-3 fatty acids enriched food supplement both in bulk oil and oil-in-water emulsions model systems. Chemical analysis revealed the presence of three major tentatively identified compounds malvidin-3,5-diglucoside, delphinidin-3,5-diglucoside and peonidin-3,5-diglucoside as major components of the extract. Test extract did not show any cytotoxic potential at recommended dosage level with LC50> 1000 µg/ml. The results provide evidence that anthocyanin-rich hydro ethanol extract of Syzygium cumini fruit pulp may serve as a potential source of safe and effective, novel natural antioxidant for retarding oxidation of omega-3 fatty acids enriched food supplement which subsequently may help to develop omega-3 fortified stable functional foods in food industry.