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Abstract Microalgae biofilms have been demonstrated to recover nutrients from wastewater and serve as biomass feedstock for bioproducts. However, there is a need to develop a platform to quantitatively describe microalgae biofilm production, which can provide guidance and insights for improving biomass areal productivity and nutrient uptake efficiency. This paper proposes a unified experimental and theoretical framework to investigate algae biofilm growth on a rotating algae biofilm reactor (RABR). Experimental laboratory setups are used to conduct controlled experiments on testing environmental and operational factors for RABRs. We propose a differential–integral equation‐based mathematical model for microalgae biofilm cultivation guided by laboratory experimental findings. The predictive mathematical model development is coordinated with laboratory experiments of biofilm areal productivity associated with ammonia and inorganic phosphorus uptake by RABRs. The unified experimental and theoretical tool is used to investigate the effects of RABR rotating velocity, duty cycle (DC), and light intensity on algae biofilm growth, areal productivity, nutrient uptake efficiency, and energy efficiency in wastewater treatment. Our framework indicates that maintaining a reasonable light intensity range improves biomass areal productivity and nutrient uptake efficiency. Our framework also indicates that faster RABR rotation benefits biomass areal productivity. However, maximizing the nutrient uptake efficiency requires a reasonably low RABR rotating speed. Energy efficiency is strongly correlated with RABR rotating speed and DC.
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This content will become publicly available on November 1, 2026
Engineering Approaches for Sustainable Protein Production in Microalgae: A Comprehensive Review
ABSTRACT The continuously growing demand for dietary protein raises the urgency of expanding supply chains beyond conventional animal‐based sources. Microalgae are well‐known as biofactories due to their high photosynthetic efficiency, rapid growth, minimal resource requirements, and ability to thrive in diverse environments. To maximize protein production, mixotrophic cultivation is often preferred, as it enables significantly higher biomass yields. Key factors, including light quality (intensity and wavelength), carbon sources (inorganic CO2and organic substrates), and nitrogen availability, play significant roles in directing metabolic fluxes toward protein biosynthesis, the modulation of which refers to biochemical engineering. In the field of genetic engineering, precise gene editing tools, especially CRISPR/Cas9, have demonstrated considerable promise, although the application in enhancing microalgal protein production remains challenging and limited. By contrast, random mutagenesis has been proven effective in improving multiple strains for increased protein accumulation. Beyond upstream strategies, downstream engineering, including drying, extrusion forming, and fermentation, is emphasized for improving the nutritional and functional properties of microalgal proteins for food and feed applications in the form of whole cells. Furthermore, extracted microalgal proteins broaden the range of potential applications, whose quality is significantly affected by the methods used for cell disruption/extraction, purification, and hydrolysis. Novel biorefinery strategies are also discussed to enhance economic viability by integrating value‐added biomass utilization within a protein‐first recovery scheme. Altogether, by combining advances in cultivation technologies, strain modification, processing, and supportive policy frameworks, this review supports the development of sustainable protein production platforms based on microalgae.
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- Award ID(s):
- 2328159
- PAR ID:
- 10655766
- Publisher / Repository:
- Comprehensive Reviews in Food Science and Food Safety
- Date Published:
- Journal Name:
- Comprehensive Reviews in Food Science and Food Safety
- Volume:
- 24
- Issue:
- 6
- ISSN:
- 1541-4337
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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