A novel, validated, eco-friendly, and cost-effective rp-HPLC method for the determination of alginic acid content in seaweed, seaweed formulations, and other higher plant extracts

Abstract

<div><p>Alginic acid products are widely used in all fields, and the main source of alginic acid is seaweed. Alginic acid varies in various varieties of seaweed, plant parts, season to season, and the temperature of the water in which it is grown. The content of alginic acid also varies from manufacturer to manufacturer, as it depends on the process of extraction. No full-proof method for quantification is available. As alginic acid became a point of concern for regulators, a robust method for quantifying alginic acid became a prime requirement. As seaweed is only considered a source of alginic acid, essential amino acids, and nonessential amino acids, other sources need to be identified to overcome future needs and maintain biodiversity. The author succeeds in identifying another source of alginic acid, nutrients, and amino acids, i.e., <em>Chromolaena odorata</em> leaf extract, which contains about 5 to 6% alginic acid and 30 to 40% amino acids and proteins. A novel RP-HPLC method was found to be simple, suitable, and robust for the determination of alginic acid content in seaweed extract, its formulations, and also in phytoextracts (<em>Chromolaena odorata</em> leaf extract). The alginic acid content in seaweed and the formulated product quantified shows 10.05 ± 0.1% and 1.0 ± 0.03%, respectively, and is in close agreement with the declared content. Various authors have used gravimetric, colorimetric, titrimetric, and HPLC methods, each with their own limitations. The novel method is simple in terms of sensitivity, eco-friendly mobile phase, regular HPLC column and detector, lowest retention time (rapid analysis), and no internal standard required.</p></div>