Edible microalgae and their bioactive compounds in the prevention and treatment of metabolic alterations

Abstract

Marine and freshwater algae and their products are in growing demand worldwide because of their nutritional and functional properties. Microalgae (unicellular algae) are probably one of the foods of the future for nutritional and environmental reasons. They are sources of high-quality protein and bioactive molecules with potential application against the modern epidemics of obesity and diabetes while they may decisively contribute to a sustainable world through carbon dioxide fixation and minimization of agricultural land use. This paper reviews the current knowledge related to the effect of edible microalgae on the metabolic alterations known as metabolic syndrome (MS). The microalgae include Chlorella, Spirulina (Arthrospira spp.) and Tetraselmis spp., as well as Isochrysis spp. and Nannochloropsis spp. as candidates for use in humans. Chlorella has shown antioxidant, antidiabetic, immunomodulatory, antihypertensive, and antihyperlipidemic effects in humans and other mammals. The components of the microalgae reviewed is suggesting they may be effective against MS at two levels, namely the early stages in the development of insulin resistance (IR) and the later stages when pancreatic -cell function is already compromised. The active components could act at both levels because of their biochemical properties as antioxidant scavengers and anti-inflammatory lipid mediators. Their action should be attributed to the presence of carotenoids and -3 PUFAs (EPA/DHA), prebiotic polysac-charides, phenolics, anti-hypertensive peptides, several pigments such as phycobilins and phycocyanin, and some vitamins such as folate. As a source of high-quality protein, including an array of bioactive molecules with potential action against the modern epidemics of obesity and diabetes, microalgae are proposed as excellent food for the future. Moreover, their incorporation to human diet would decisively contribute to a more sustainable world because of their role in carbon dioxide fixation and reducing the use of land for agricultural purposes.