Nutrient profiling and in-vitro antioxidant activity assessment of selected red seaweed species of North-west coast of India

Aim: Seaweed offers benefits over many terrestrial crops and can be used as food and feed ingredients. The objective was to study the nutritional value of particular red seaweeds. Methodology: Three species of red seaweed namely Centroceras clavulatum, Acanthophora specifera and Amphiora ancep from Wayangani coast, Ratnagiri, Maharashtra and two species such as Hylimenia venkata and Hylimenia venusta from Okha coast, Gujarat were collected and screened for biochemical characteristics, carotenoid composition, in-vitro antioxidant activity. Results: The seaweed proximate composition: crude protein, fat, total ash, crude fiber and nitrogen free extract ranged between 4.17-13.12, 0.44-0.91, 37.27-63.82, 2.43-6.07, 26.07-44.92 %, respectively. All the seaweed species contained lutein and zeaxanthin, xanthophyll carotenoids. The range of the total phenolic content was 180.92-375.16 mg GAE/g. The % DPPH radical scavenging capacity ranged from 41.32-73.78%. The strongest positive association was found between TPC (r= 0.821, P=0.088) and total carotenoid; while the highest correlation was found between the antioxidant activity and TPC (r= 0.920, P=0.027). Interpretation: H. venusta exhibits exceptional properties and significant potential as a functional ingredient in fish feed, contributing to enhanced aquaculture nutrition and sustainability. Key words: Antioxidants, Biochemical composition, Carotenoids, Minerals, Red seaweed