Kinetic modeling of microalgal growth and lipid synthesis for biodiesel production

Abstract

A mathematical modeling of microalgae biomass is an essential step to optimize the biomass and lipid production rate and to reduce the cost of microalgal biodiesel production system. In the present study, kinetic studies were carried out to describe the growth and neutral lipid production of two marine microalgae Chlorella salina and Nannochloropsis oculata under the nitrogen-repleted and -depleted conditions using logistic and Luedeking–Piret equations. This research paper provides the information on mathematically efficient procedure to predict suitable environment condition for biomass and lipid production. The predicted results were compared with experimental data, which showed that this model closely agreed with simulated results. From this investigation, it was found that nitrogen was an essential nutrient for algal growth, which increased under nitrogen-rich condition, whereas during nitrogen-limited condition some loss in growth was observed but with increased lipid content. Since metabolic changes occurred under nitrogen- depleted state, the protein and carbohydrate pathways were shifted to lipid biosynthesis.

Induction of oil accumulation by heat stress is metabolically distinct from N stress in the green microalgae Coccomyxa subellipsoidea C169

“…Therefore, we modeled C . subellipsoidea growth using a logistic model displaying a lag phase, an initial growth rate, and stationary state with sigmoidal curve [ 27 – 29 ]. To evaluate and compare the maximum specific growth rates of C169 at different temperatures, we performed kinetic modeling using the logistic approach to the experimental growth data using Eq ( 2 ).…”

“…An unstructured typical kinetic model used widely is the Leudeking-Piret approach, which can model both the growth and non-growth-associated phenomena for product (P) formation of TAG, starch, and chlorophyll [ 27 – 29 ]: Eq ( 4 ) shows that product formation rate depends linearly on the growth rate and the cell concentration. In this equation, the product formation rate can be contributed by (i) growth related ( α , mg-product per mg-biomass) coefficient, and (ii) non-growth related ( β , mg-product per mg-biomass per day) coefficient.…”

Cultivation of Chlorella mutant in cellulosic ethanol wastewater using a static mixing airlift photo‐bioreactor for simultaneous wastewater treatment

“…The nitrogen source and the N/P ratio in wastewater have direct effects on microalgal growth and the removal rates of substrates such as nitrogen and phosphorous. It was reported that when ammonia was used as a nitrogen source, the removal rates of nitrogen and phosphorus were higher than those with nitrate, and a ratio of N/P at 7:1–8:1 was proper for the growth of microalgae . In this study, the main type of nitrogen in the CEW was ammonia which was more easily to be removed, showing highly efficient treatment of wastewater by Chlorella vulgaris CEW‐1.…”

Comparação De Métodos De Ruptura Celular E Extração De Lipídios De Biomassa Perifítica

“…As células das microalgas tendem a produzir lipídios em maior quantidade quando são submetidas a condições de cultivo sob estresse, isto é, em condições de escassez de nitrogênio, que revertem o metabolismo de carboidratos e proteínas para lipídios (SURENDHIRAN et al, 2015).…”