Microalgae as Raw Materials for Aquafeeds: Growth Kinetics and Improvement Strategies of Polyunsaturated Fatty Acids Production

Abstract

Studies have shown that ancient cultures used microalgae as food for centuries. Currently, scientific reports highlight the value of nutritional composition of microalgae and their ability to accumulate polyunsaturated fatty acids at certain operational conditions. These characteristics are gaining increasing interest for the aquaculture industry which is searching for cost-effective replacements for fish meal and oil because these commodities are one of the most significant operational expenses and their dependency has become a bottleneck for their sustainable development of the aquaculture industry. This review is aimed at highlighting the use of microalgae as polyunsaturated fatty acid source in aquaculture feed formulations, despite their scarce production at industrial scale. Moreover, this document includes several approaches to improve microalgae production and to increase the content of polyunsaturated fatty acids with emphasis in the accumulation of DHA, EPA, and ARA. Furthermore, the document compiles several studies which prove microalgae-based aquafeeds for marine and freshwater species. Finally, the study explores the aspects that intervene in production kinetics and improvement strategies with possibilities for upscaling and facing main challenges of using microalgae in the commercial production of aquafeeds.

Microalgae Technology in Aquaculture Applications: A Comprehensive Literature Review

“…Additionally, there are some research gaps include understanding nutrient assimilation (Kosten et al, 2020;X. Yang et al, 2020)., algal-bacterial cooperation (Falaise et al, 2016), economic assessments (Soto-Sánchez et al, 2023), biomass harvesting optimization (BASHIR et al, 2022), scaling production (Han et al, 2019), strain selection, and region-specific studies (Ayswaria et al, 2023). Advancements like natural antibiotics, improved biomass production, genetic engineering, economic assessments, biomass valorization, algal-bacterial interactions, and disease prevention applications hold potential to enhance microalgae technology for sustainable aquaculture (Y.…”

“…These applications extend to biofuels, cosmetics, and bioremediation (Balasubramaniam et al, 2021). Cultivation of microalgae on a large scale with a rapid growth rate positions them as a sustainable biomass source for numerous industries (Soto-Sánchez et al, 2023). Phytosterols, a vital bioactive compound found in microalgae, have been incorporated as food additives in various products like spreads, dairy items, and salad dressings (X.…”

“…Luo et al, 2015). Microalgae are also rich in polyunsaturated fatty acids (PUFAs), acknowledged for their health-promoting properties (Soto-Sánchez et al, 2023). However, challenges persist in commercial microalgae production and bioactive compound extraction, necessitating research for optimal yield and genetic enhancements (Kumar et al, 2020).…”

Nannochloropsis as an Emerging Algal Chassis for Light-Driven Synthesis of Lipids and High-Value Products

“…In comparison to the wildtype N. oceanica, the overexpression of AtDGAT resulted in a significant increase in C16 (C16:0 + C16:1) levels and a slight decrease in C18 (C18:0 + C18:1), providing novel insights into the genetic engineering of oleaginous microalgae [4]. In addition, there have been many studies exploring Nannochloropsis as feed for Pacific white shrimp, Atlantic salmon, kuruma shrimp, and European sea bass [5,6]. Adissin et al [7] used algal powder to take the place of fish oil and finally improved shrimp growth.…”

Applications of Microalgae in Foods, Pharma and Feeds and Their Use as Fertilizers and Biostimulants: Legislation and Regulatory Aspects for Consideration

“…When in perfect environmental conditions, microalgae can grow extremely fast and it is estimated that the growth of algae can be up to 10 times quicker than land-based, conventional crops [5], making them a potentially sustainable source of feed ingredients. Microalgae use as food is not new and dates back to Aztec times but there is growing demand for food ingredients [6], feed ingredients [7], and agents for water purification [8] that are of algal origin. Moreover, they are known for their potential use as biofuels in renewable energy [9], as well as ingredients for use in biostimulants [10], cosmetic compounds [11] and healthcare products.…”