From ocean depths to nutrient rich plates: A comparative study on the toxicity, nutritional composition and antioxidant potential of selected seaweeds
Author(s): S Adithiyalakshmi, Salnamchi J Sangma and PL Sridevi Sivakami
Abstract: Seaweeds, thriving in intertidal, shallow, and deep waters, are rich reservoirs of proteins, essential amino acids, fatty acids, vitamins, minerals, and phytochemicals. Their unique ability to flourish in environments laden with toxic minerals underscores their potential as absorbers of such elements, necessitating a thorough toxicity analysis for safety assessment. This study focuses on Sargassum wightii and Ulva lactuca, aiming to investigate their toxicity, nutritional composition, and antioxidant potential as contributors to overall health. Collected from the Mandapam coastal area of Rameswaram, Tamil Nadu, India, both seaweeds underwent rigorous processing, including washing, drying, and powdering, followed by comprehensive analyses. Primary toxicity assessment revealed concentrations of heavy metals (Mercury, Lead, Cadmium, Arsenic) below quantifiable limits for both species, affirming their non-toxic nature. Secondary toxicity analysis, employing a brine shrimp lethality assay, indicated low toxicity levels for both Sargassum wightii and Ulva lactuca. Nutritional composition analysis unveiled diverse profiles: Sargassum wightii exhibited richness in Carbohydrates (54.97 g), Protein (5.13 g), Fat (0.21 g), Fiber (24.1 g), Calcium (32.64 mg), and Iron (0.77 mg), while Ulva lactuca excelled in Fiber (27.6 g), Calcium (878.2 mg), and Iron (2.11 mg). Phytochemical screening highlighted various bioactive compounds, and antioxidant potential, assessed through the DPPH method, showcased significant activity in Sargassum wightii compared to Ulva lactuca. In conclusion, both seaweeds demonstrated edibility, absence of toxic heavy metals, and low toxicity levels, suggesting their potential as health-promoting dietary components. Their diverse nutritional profiles and notable antioxidant activity position Sargassum wightii and Ulva lactuca as promising candidates for inclusion in balanced and nutritious diets, emphasizing their safety and potential health benefits.
