Microalgae as a Sustainable Source of Antioxidants in Animal Nutrition, Health and Livestock Development

Abstract

Microalgae are a renewable and sustainable source of bioactive compounds, such as essential amino acids, polyunsaturated fatty acids, and antioxidant compounds, that have been documented to have beneficial effects on nutrition and health. Among these natural products, the demand for natural antioxidants, as an alternative to synthetic antioxidants, has increased. The antioxidant activity of microalgae significantly varies between species and depends on growth conditions. In the last decade, microalgae have been explored in livestock animals as feed additives with the aim of improving both animals’ health and performance as well as product quality and the environmental impact of livestock. These findings are highly dependent on the composition of microalgae strain and their amount in the diet. The use of carbohydrate-active enzymes can increase nutrient bioavailability as a consequence of recalcitrant microalgae cell wall degradation, making it a promising strategy for monogastric nutrition for improving livestock productivity. The use of microalgae as an alternative to conventional feedstuffs is becoming increasingly important due to food–feed competition, land degradation, water deprivation, and climate change. However, the cost-effective production and use of microalgae is a major challenge in the near future, and their cultivation technology should be improved by reducing production costs, thus increasing profitability.

Phytohormone Supplementation for Nutrient Removal from Mariculture Wastewater by Oocystis borgei in Sequential Batch Operation

“…SOD and CAT are pivotal antioxidant enzymes in microalgal cells, with SOD acting as the first defense against oxidative stress. Moreover, carotenoids have antioxidant characteristics and maintain cells against free radicals, inhibit lipid peroxidation, increase the stability of the photosynthetic apparatus, and protect integrity membranes [86]. In this study, 10 −6 M IAA, GA3, and ZT significantly increased the levels of antioxidant enzymes SOD and CAT as well as carotenoids (Figure 3B), indicating that O. borgei enhanced antioxidant capacity in response to abiotic stress.…”

Emerging microalgal feed additives for ruminant production and sustainability

“…The inclusion of microalgae in animal diets has gained widespread attention for aquaculture, as well as the production of poultry, monogastric mammals, and ruminants (El-Ghany 2020 ; Ma et al 2024 ; Madeira et al 2017 ; Martins et al 2021 ). Microalgae are abundant in aquatic environments, possessing favorable characteristics such as rapid proliferation, widespread habtitats, and environmental adaptability, which make them easily accessible as natural food and feed sources for various aquatic organisms (Olabi et al 2023 ; Udayan et al 2021 ).…”

Light and Nutrient Conditions Influence Fucoxanthin Production of the Microalgae Cyclotella meneghiniana

“…Microalgae are of high commercial value and also produce proteins, lipids, vitamins, pigments, cosmetics, and food and feed additives [4]. Microalgae offer a renewable and sustainable way to obtain bioactive substances like essential amino acids, polyunsaturated fatty acids, and antioxidants, which have been documented to have beneficial effects on health and nutrition [5]. Prior studies have confirmed the effectiveness of microalgae in serving as a source of fucoxanthin, with diatoms exhibiting a goldenbrown hue, attributed to their richness in pigments such as fucoxanthin [6,7].…”