Antioxidant and Free Radical-Scavenging Potential of Essential Oil from E nteromorpha linza L. Prepared by Microwave-Assisted Hydrodistillation

Abstract

The seaweed Enteromorpha linza has long been used as a food source rich in natural bioactive compounds in various regions of the world. In the present study, the essential oil from E. linza, extracted by microwave-assisted hydrodistillation, was analyzed for its chemical composition and was evaluated for its free radical-scavenging and antioxidant potential. Gas chromatography and mass spectroscopy revealed the presence of 24 compounds in the seaweed essential oil (SEO), among which hexadecanoic acid (47.32%), nonadecadiene (18.19%) and azetidine (2.84%) are of medicinal importance. SEO exhibited strong hydroxyl radical-scavenging and superoxide scavenging activity of 91.37 and 53.50%, respectively, at 500 μg/mL. SEO also exhibited strong reducing power (0.90) and inhibited lipid peroxidation by 70.53% at 500 μg/mL. Based on the high antioxidant activities of compounds in SEO, it can be used as a food additive, preservative and dietary supplement to control the deleterious effects of oxidative stress with increased nutritional values. Practical Applications Extensive investigations of free radicals and reactive oxygen species have revealed that these components have adverse effect on biomolecules that cause damage to macromolecules, including proteins, nucleic acids, lipids and carbohydrates, as well as various food products. Seaweeds are a favorable food source that serves as an effective resource for essential oil, which could be an alternative source of natural antioxidants, used as food additives or in food preservation. In this study, SEO from E. linza extracted by microwave-assisted hydrodistillation exhibited significantly high antioxidant and radical-scavenging potential, as well as inhibition of lipid peroxidation. These findings confirm that SEO from E. linza can be used by food industries as an additive, preservative or dietary supplement and as a nutraceutical to control the harmful effects of oxidative stress on food.