Growth parameter estimation and model simulation for three industrially relevant microalgae: Picochlorum, Nannochloropsis, and Neochloris

Abstract

Multiple models have been developed in the field to simulate growth and product accumulation of microalgal cultures. These models heavily depend on the accurate estimation of growth parameters. In this paper growth parameters are presented for three industrially relevant microalgae species: Nannochloropsis sp., Neochloris oleoabundans, and Picochlorum sp. (BPE23). Dedicated growth experiments were done in photobioreactors to determine the maximal biomass yield on light and maintenance rate, while oxygen evolution experiments were performed to estimate the maximal specific growth rate. Picochlorum sp. exhibited the highest specific growth rate of 4.98 ± 0.24 day −1 and the lowest specific maintenance rate of 0.079 day −1 , whereas N. oleoabundans showed the highest biomass yield on light of 1.78 g x •mol ph −1 . The measured growth parameters were used in a simple kinetic growth model for verification. When simulating growth under light conditions as found at Bonaire (12 °N, 68°W), Picochlorum sp. displayed the highest areal biomass productivity of 32.2 g.m −2 •day −1 and photosynthetic efficiency of 2.8%. The

Thermotolerant microalgae : bioprospecting followed by adaptive laboratory evolution for strain selection and improvement

“…Mut4 and mut11 displayed a maximal specific growth rate of 5.45 ± 0.23 d -1 and 5.71 ± 0.14 d -1 , respectively, which is significantly higher than the maximal specific growth rate of the wildtype, 3.35 ± 0.15 d -1 . The growth rate of the wildtype strain, grown on nitrate is comparable to values reported in previous research [157].…”

“…Algaemist photobioreactors (Technical Development studio, WUR, The Netherlands) were used for characterization and comparison of growth characteristics and RNA expression patterns of the wildtype and two evolved strains of Picochlorum sp. BPE23 [157]. Cells were grown in turbidostat mode with similar growth conditions as in "paragraph 2.1.2.…”

“…Biomass harvest and biomass lyophilization, determination of pigments through HPLC, and determination of fatty acids through GC was performed as described in [150]. The photosynthesis irradiance curve and the maximal specific growth rate were measured as described in [157].…”

“…Microalgal strains naturally exhibit different biomass yields on light. However, causes for these differences are difficult to determine, and examples in literature are mostly speculative [157]. Potential causes for the increased photosynthetic efficiency are an increased photochemical efficiency, altered antenna size and filtering pigment composition, and an altered biomass composition [6,182].…”

Analysis and Modeling of Innovations in the Global Microalgae Lipids Market

“…Computational models are gaining attention with advanced software that may be employed for pathway prediction, data analysis, and optimization of bioproducts in microalgae cultivation [ 12 , 13 ]. Banerjee et al [ 12 ] showed the importance of computational modeling and prediction of microalgae growth focused on improved lipid production.…”