Aquaculture sustainability through alternative dietary ingredients: Microalgal value-added products

Aquaculture contributes remarkably to the global economy and food security through seafood production, an important part of the global food supply chain. The success of this industry depends heavily on aquafeeds, and the nutritional composition of the feed is an important factor for the quality, productivity, and profitability of aquaculture species. The sustainability of the aquaculture industry depends on the accessibility of quality feed ingredients, such as fishmeal and fish oil. These traditional feedstuffs are under increasing significant pressure due to the rapid expansion of aquaculture for human consumption and the decline of natural fish harvest. In this review, we evaluated the development of microalgal molecules in aquaculture and expanded the use of these high-value compounds in the production of aquaculture diets. Microalgae-derived functional ingredients emerged as one of the promising alternatives for aquafeed production with positive health benefits. Several compounds found in microalgae, including carotenoids (lutein, astaxanthin, and β-carotene), essential amino acids (leucine, valine, and threonine), β-1-3-glucan, essential oils (docosahexaenoic acid and eicosapentaenoic acid), minerals, and vitamins, are of high nutritional value to aquaculture.