Work

Selection and characterization of acid-tolerant Chlorophyta division microalgae for potential metabolites production in a bubble column bioreactor: A ready-to-industrial scale screening

Year: 2025

Type: article

Abstract: • Screening of 28 Chlorophyta strains revealed two unique kinetic behaviors for nitrate use. • Pseudococcomyxa simplex strains showed high nitrate uptake but low biomass growth rates. • Chlorella vulgaris achieved 42 % carbohydrate content with a productivity of 0.25 g/L/day. • Lipid productivity increased with growth rate, peaking at 18% in selected strains. • Extreme strains showed distinct metabolite pools, crucial for tailored industrial applications. Microalgae are promising candidates for sustainable bioprocesses owing to their ability to capture/utilize CO 2 and produce valuable metabolites. However, strain-to-strain variability poses a challenge to industrial scalability. This paper reports a study on the screening of 28 Chlorophyta microalgal strains from six species cultivated under standardized semi-continuous conditions in a bubble column bioreactor. Growth kinetics, nitrogen uptake, and metabolite accumulation were analyzed to identify strains characterized by promising biomass/metabolite productivities. The results indicated two distinct kinetic behaviors: a large fraction of the investigated strains was characterized by a common biomass/nitrate uptake behavior, and a subset of the strain pool was characterized by atypical nitrogen assimilation patterns. Strains characterized by high biomass growth rates are characterized by high lipid productivity. Strains with intermediate biomass growth rates are characterized by high carbohydrate accumulation. Chlorella vulgaris (ACUF 058) and Chloroidium saccharophilum (ACUF 050) emerged as strong candidates for carbohydrate and protein production, respectively. This study proposed a systematic procedure for strain selection, bridging laboratory screening, and industrial feasibility. These results emphasize the role of tailored cultivation strategies in optimizing biomass yield and metabolite productivity. Further research integrating genomic and proteomic insights will enhance strain-specific process optimization, facilitating the large-scale deployment of microalgal bioprocesses.

Source: Bioresource Technology

DOI: 10.1016/j.biortech.2025.132579

Authors: Luigi Marra, Elena Aurino, Francesca Raganati, Antonino Pollio, Antonio Marzocchella

Institution: University of Naples Federico II

Language: English

Topic: Algal biology and biofuel production

Subfield: Renewable Energy, Sustainability and the Environment

Field: Energy

Domain: Physical Sciences

SDG: Responsible consumption and production

Open Access status: hybrid

Estimated APC paid: $4,880