GC-MS Based Phytochemical Profiling and Antioxidant-Nutraceutical Relevance of Kappaphycus alvarezii

Abstract

Marine red algae are recognized as significant sources of bioactive compounds with potent antioxidantand nutraceutical attributes. This study thoroughly examined ethanolic and methanolic extracts ofKappaphycus alvarezii by a dual analytical methodology: comprehensive antioxidant assay profiling(DPPH, ABTS, FRAP, ORAC) and GC–MS chemical characterization. Antioxidant assays exhibitedconsiderable radical scavenging and reducing properties, particularly in ethanolic extracts (DPPH IC₅₀:43 μg/mL; ABTS IC₅₀: 46 and methanolic extracts FRAP: 774 μM TEAC/g; ORAC: 722 μmol TE/g),indicating strong activity through both SET and HAT mechanisms. The GC-MS investigation showed29 distinct peaks, which were made up of phenolic antioxidants, aliphatic hydrocarbons, alkenes, fattyacids, and minor esters. 2,4-Di-tert-butylphenol (13.02%, RT 14.04 min) was an important antioxidantmarker, and a significant hydrocarbon peak (18.37%) changed the overall profile a lot. The extract'sbioactivity is greatly enhanced by the addition of Artonin L monomethyl ether, a methoxylatedpolyphenolic flavonoid. The chemical makeup and functional antioxidant evidence reveal thatKappaphycus alvarezii is a great source of natural antioxidants and functional bio actives from the sea.It could be used in functional foods, dietary supplements, and medicines.