Screening of Ulva rigida, Gracilaria sp., Fucus vesiculosus and Saccharina latissima as Functional Ingredients

Abstract

The intent of the present work was to evaluate the potential of four macroalgae prevalent in Europe, namely Ulva rigida, Gracilaria sp., Fucus vesiculosus and Saccharina latissima, for application in functional foods, either in the direct form or as extracts. Accordingly, nutritional composition, the content of phytochemical antioxidants, and the inhibitory ability of key enzymes with impacts on obesity and diabetes (α-glucosidase and pancreatic lipase) or on arterial pressure (angiotensin-I converting enzyme), were evaluated. Overall, protein, lipid, ash and fiber contents of the macroalgae ranged from 9–24% dw, 0.5–3.0% dw, 20–32% dw, and 37–45% dw, respectively, making them good candidates for nutritional supplementation of several foods, particularly due to their mineral and fiber contents. In addition, brown macroalgae, in particular F. vesiculosus, stood out for its superior phenolic content, which was reflected by its high antioxidant ability and inhibition towards α-glucosidase activity (0.032 mg/mL of hydroacetonic extract inhibited 50% of the enzyme activity).

Seaweed’s Bioactive Candidate Compounds to Food Industry and Global Food Security

“…The ideal ratio of ω-6:ω-3 should range from 3:1 to 5:1 and it is associated with a reduction in the risk of cardiovascular and other chronic diseases, such as diabetes, and the improvement of the immune response and brain function [119,128,129]. On average, this ratio ranges from 0.1 to 8.2 in red species, from 0.2 to 2 in green species, and 0.2 to 2.4 in brown species [52,101,106,[130][131][132][133][134]. Thus, consumption of seaweed products should be encouraged as they offer these health-promoting PUFAs.…”

Effect of Food Preparations on In Vitro Bioactivities and Chemical Components of Fucus vesiculosus

“…Macroalgae have been used for centuries as a source of food, fuel, feed, and agricultural fertilizers [1]. The consumption of seaweeds has been growing in the past years because people are looking for a more environmentally friendly and healthier lifestyle, being aware of the influence of diet on health and well-being [2,3]. The global seaweed industry produces approximately 12 million tons per annum in volume of which 85 percent comprises food products [4].…”

“…Phlorotannins, the phenolic compounds high in concentration in brown algae, are highly hydrophilic, have a molecular size from 234 to more than 100,000 Da [14] and are composed of oligomers of phloroglucinol (1,3, [15]. According to different studies, phlorotannins reaches 15% of F. vesiculosus dry weight and are characterized by low toxicity and high antioxidant activity [16,17].…”

“…According to different studies, phlorotannins reaches 15% of F. vesiculosus dry weight and are characterized by low toxicity and high antioxidant activity [ 16 , 17 ]. Phlorotannins have also been described as having in vitro anti-cancer, anti-diabetic, anti-lipidemic, and anti-hypertensive activities, among others [ 6 , 18 , 19 , 20 ] and therefore have been used as food additives [ 3 ].…”

Ulva lactuca, A Source of Troubles and Potential Riches

“…Alginate, one of the main structural polymers of brown seaweeds, provides both stability and flexibility for the specimens exposed to flowing water, and is one of the industrially-relevant carbohydrate compounds found in seaweed biomass, as are other hydrocolloids, such as agar and carrageenans, which are commonly used as thickeners, gelling agents or emulsifiers. Various other non-carbohydrate products obtained from seaweeds include protein, lipids, phenols and terpenoids, and minerals such as iodine, potash and phosphorus—useful for human and animal nutrition [8]. The harvesting of macroalgae—a valuable raw material for food—before they beach could well be developed into an effective solution [9].…”