Ascophyllum nodosum is a common brown alga that is found easily in the Atlantic ocean. Usually, it is called as knotted wrack, knotted kelp, Norwegian kelp, or egg wrack due to its shape. This seaweed grows in branched fronds with egg-shaped air bladders. Similar to other species of seaweeds, it has a protective factor that is against the sun rays. Various minerals in the knotted wrack act as key ingredients for human health when consumed as food sources.

Several studies have shown that knotted wrack is rich in actives such as vitamins, polysaccharides, and polyphenols. These active compounds from knotted wrack extract show the anti-inflammatory effect by suppressing the pro-inflammatory cytokines. Also, its anti-oxidant effect has been revealed by showing the suppression of ROS generation on epithelial cells.