The sea lettuce Ulva sensu lato: Future food with health-promoting bioactives

Abstract

Marine green macroalgae are a valuable natural resource for bioactive phytochemicals that have potential applications in therapeutics, even though they remain largely under-exploited. Green macroalgae Ulva or sea lettuce species are found at all levels of the intertidal zone that grows along rocky or sandy coasts of oceans and seas. Green algae are found in unicellular, colonial, and multicellular forms. Apart from carotenoids, Ulva is a good source of vitamin B, proteins, minerals (calcium, potassium, magnesium, sodium, copper, iron, and iodine), and dietary fibers. Ulva lactuca is a macroalgae grown widely along the Mediterranean coast, belongs to the phylum Chlorophyta, and is commonly known as “Sea lettuce”. U. lactuca contains about 13.6 % protein on a dry weight basis. Nutrient-dense U. lactuca is used as salad and also in kimchi preparations. This review highlights the chemistry, structure, and food and pharmaceutical applications of bioactives in green seaweeds and Ulva spp. precisely to exploit as a future superfood material owing to its nutraceutical properties and pharmaceutical applications just like brown algae Wakame. Hence, research in this area is opening entries for connecting the potential of marine natural products. While there are several reviews highlighting the biological and pharmaceutical activities of marine algae and their-derived bioactives especially sulfated polysaccharides and lipids, reports on future food applications are sparse. Therefore, the present review provides details on recent progress in green algae and food applications due to their nutritional potential.