Comprehensive analysis of dehydrated edible macroalgae: Volatile compounds, chemical profiles, biological activities, and cytotoxicity

Abstract Seaweeds offer sustainable, low-calorie nutritional options to address global food demand. Their limited use is due to a lack of understanding of their flavor, influenced by volatile organic compounds (VOCs). This study aims to expand knowledge of sensory, bioactive, and chemical properties of edible macroalgae ( Chondrus crispus, Gracilaria gracilis, Porphyra dioica, Pyropia haitanensis, Palmaria palmata, and Ulva rigida ) analyzing their VOCs, phenolics, proteins, free amino acids, sugars, and bioactivities. Extracts were obtained using 80% ethanol (25ºC, 60 min). HS-SPME/GC–MS analyses identified distinct compounds, such as 3-methyl-1-butanol, 2-ethyl-1-hexanol, geranylacetone, trans -linalool oxide, and trimethylpyrazine in P. haitanensis , ( Z )-4-heptenal in P. dioica , octanal, isophorone, heptanoic acid, 2,6-dimethylpyrazine, and tetramethylpyrazine in P. palmata , 2-methyl-2-pentenal, 1-pentanol, and 1-hexanol in G. gracilis , ( E )-2-pentenal, ( E , E )-2,4-heptadienal, 5-ethyl-2-furaldehyde, α-terpineol, and α-muurolene in U. rigida . Novel compounds were discovered in P. haitanensis (20), P. palmata (4), C. crispus (10), U. rigida (14), G. gracilis (11), and P. dioica (19). Red algae, especially Porphyra / Pyropia and P. palmata , were rich in phenolics, proteins, and sugars. P. haitanensis showed the strongest antioxidant and anti-inflammatory properties, while P. dioica demonstrated lipid peroxidation prevention. These results, with the safe profile of all evaluated macroalgae, underscore the potential of seaweeds as innovative nutritional and bioactive food ingredients.