Microalga‐ and yeast‐based astaxanthin production via nutrient recovery from wastewater for aquaculture practice: an emerging technology for sustainable development

Abstract

Microbial astaxanthin, which is a high‐value antioxidative pigment, has been widely used in aquaculture for pigmentation, immunity enhancement and disease resistance. This novel model is regarded as an emerging way to alleviate environmental pollution and ecological problems. Therefore, cultivation of astaxanthin‐rich microorganisms for aquaculture merits attention of researchers and technicians. This paper presents research progresses in microbial strain screening, astaxanthin formation pathways and inducing conditions. Particularly, two‐stage cultivation, which could effectively improve astaxanthin productivity in microorganisms, is summarized. In addition, the integration of microorganism cultivation with wastewater remediation to simultaneously lower the production cost of astaxanthin and create environmental benefits is discussed. Last but not least, an in‐depth discussion of the effect of extracted astaxanthin or astaxanthin‐rich biomass on fish/shrimp rearing is provided. Based on a literature review and the present authors’ experience in industry, this paper lists some problems, such as safety risks of microbial biomass and potential ecological disasters. Besides, potential solutions and prospects are discussed to promote the further development of astaxanthin‐related industry. © 2022 Society of Chemical Industry (SCI).

Cultivation of microalgae in food processing effluent for pollution attenuation and astaxanthin production: a review of technological innovation and downstream application

“…Secondly, astaxanthin formation is accompanied with the encystment induced under the high ratio of C/N ( Kakizono et al, 1992 ; Li et al, 2022 ). Traditionally, to grow microalgae for astaxanthin production, low concentration of nitrate, ammonia, or organic nitrogen was added in artificial medium ( Lu and Lu, 2022 ). As shown in Table 3 , however, many FPEs, such as soybean processing effluent and meat processing effluent, contain high concentration of TN.…”

“…In a real-world application, however, high cost of natural astaxanthin production by microalgae cultivation has not been fully addressed. In the market, high sale price (US $2,000–2,500 per kilogram) of natural astaxanthin is hindering the wide application of this valuable bio-product in modern agriculture ( Liu et al, 2013 ; Lu and Lu, 2022 ).…”

Effect of salt stress on the biomass productivity and potential bioenergy feedstock of Graesiella emersonii KNUA204 isolated from Ulleungdo Island, South Korea

“…However, other studies have revealed that under high salt stress conditions, the fatty acids in membrane lipids become unsaturated, resulting in an increase in the proportion of unsaturated fatty acids and a decrease in that of saturated fatty acids (Atikij et al, 2019). Not only lipid but also carotenoid content increased under salinity stress, especially MgCl2, and NaCl (Kobayashi et al, 1997;Rad et al, 2011;Pourkarimi et al, 2020;Lu and Lu, 2022).…”

Challenges and potential solutions of microalgae-based systems for wastewater treatment and resource recovery

“…Firstly, microalgae could remove/reduce nutrients, organic pollutants, heavy metals, chemical oxygen demand (COD), and biological oxygen demand (BOD) in wastewater effectively ( Song et al, 2022 ). Secondly, algal biomass cultivated in wastewater could be used as a potential source of precious products that could be utilized in biofuels, cosmetics, pharmaceuticals, and nutraceuticals fields ( Li et al, 2021 ; Lu and Lu, 2022 ; Lu and Xiao, 2022 ). Thirdly, the microalgae-driven wastewater treatment could help to realize the integration of wastewater treatment, industrial CO 2 sequestration and microalgal biomass valorization, and shift wastewater treatment from linear economy to circular economy ( Vaz et al, 2023 ).…”