Evaluation of the proximate composition, minerals, and heavy metals of brown seaweeds: Sargassum wightii and Sargassum thunbergii collected from the Mandapam coastal regions, Tamil Nadu

Abstract

A vital renewable resource for the marine environment, seaweed naturally supplies nutrients and has several health benefits. The nutritional properties of seaweed compounds have yet to be well investigated; much research has been done on their chemical and biological makeup. Seaweeds provide an alternate supply of these essential nutrients, including protein, fibre, and necessary and non-essential trace elements. In the present study, two brown seaweeds-Sargassum wightii and Sargassum thunbergii,collected from the Mandapam coastal region of Tamil Nadu, were assessed for their proximate composition, minerals, and heavy metals.The findings on dry weight basis showed that carbohydrates (65.1–67.9%) predominated in the proximal analysis, followed by ash content (12.5–16.3%). On a dry weight basis, the critical trace elements found in seaweeds, such as copper (Cu), zinc (Zn), and iron (Fe), were between 8.14–12.41 ppm, 3.95–4.86 ppm, and 648.92-898.45 ppm, respectively. Both seaweeds have a very high calcium (Ca) concentration, ranging from (14,805.08-16,235.62) ppm. The seaweed species did not contain any measurable levels of dangerous heavy metals such as cadmium (Cd), beryllium (Be), lead (Pb), or mercury (Hg). The results demonstrated how seaweed or marine macroalgae may be helpful for essential nutrient supply.