Table 1.

List of macroalgae sources, bioactive molecules and compounds, and their applications.

Seaweed	Group	Compound	Source	Use	Bioactivity Reported	Reference
Brown seaweed (Phaeophyta)
Brown	Polyphenol	Phlorotannins	Ascophhyllum nodosum, Eisenia arborea, Fucus spp., and Sargassum spp.	Modulate gut microbiota.	Antimicrobial and bacterial inhibitor. Anti-inflammatory effects.	[51,52,53]
Brown	Polysaccharide	Alginate	Phaeophyceae spp.	Numerous applications in food and biotechnology. Gelling abilities, stabilizing, water holding capability.	Antioxidant, Anti-inflammatory, antimicrobial, and antitumor properties. Growth-promoting effects in plants and animals.	[54,55,56]
Brown	Polysaccharide	Fucoidan	Cladosiphon novae caledoniae, Fucus vesiculosus, Hizikia fusiformis, Phaeophyceae spp., Saccharina japonica, Sargassum crassifolium, and Undaria pinnatifida	Functional foods and nutraceuticals. Prebiotic properties.	Antioxidant, anti-inflammatory, antiangiogenic, anticoagulant, immunomodulatory, anti-adhesive, antitumoral, antidiabetic, antimicrobial, and anti-neurodegenerative.	[57,58]
Brown	Polysaccharide	Laminarin	Laminaria spp.	Source of arabinose, galactose, mannose, xylose, glucose, rhamnose, and glucuronic acid.	Antitumour, antihyperglycaemic, and antihyperlipidaemic agents (mouse model).	[9,59]
Red seaweed (Rhodophyta)
Red	Polysaccharide	Agar	Agarophyton vermiculophyllum, Gelidium spp.	Gelling thickener and clarifying agent.	Enhance bifidobacterial populations (in vitro). Increase complement pathway activity in fish (Pangasius bocourti).	[1,60,61]
Red	Polysaccharide	Carrageenan	Furcellariaceae spp., Gigartinaceae spp., Hypneaceae spp., Phyllophoraceae spp., and Solieriaceae spp.	Gelling, thickening, emulsifying and stabilizing agents. These are the functional ingredients commonly found in vegetable-based products, dairy, baked items, meat, and fish.	Antioxidant, antiviral, antibacterial, antihyperlipidemic, anticoagulant, anticancer, and immunomodulatory effects.	[49,62,63]
Red	Protein	Allophycocyanin, Phycocyanin, Phycoerythrin, and Phycoerythrocyanins	C. crispus, G. gracilis, G. turuturu, Gelidium amansii. Porphyra spp., Porphyridium cruentum, and Rhodosorus marinus	Colorants for food and cosmetics Immune system improvement.	Antioxidant, antitumoral, antidiabetic, anti-inflammatory, antioxidative, and anti-irradiative effects.	[64,65,66,67]
Green seaweed (Chlorophyta)
Green	Polysaccharide	Ulvan	Entermorpha sp. and Ulva sp.	Gelling and rheological properties like gum arabic.	Antibacterial antitumor, antioxidant, anti-thrombolytic, immunomodulation, antiviral, and anticoagulant activity, pharmacokinetics, oxidative and thermal stability	[57,62,68]