Simultaneous enhancement of lipid biosynthesis and solvent extraction of Chlorella using aminoclay nanoparticles.

[Display omitted] • Magnesium aminoclay (MgA) induces CO 2 absorption and oxidative stress. • The effect of MgA on growth and lipid accumulation is Chlorella strain-dependent. • MgA improved the total lipid content and hexane extractability of Chlorella KR-1. • MgA promoted triacylglycerol biosynthesis but reduced cell wall thickness. Magnesium aminoclay nanoparticles (MgANs) exert opposing effects on photosynthetic microalgae by promoting carbon dioxide (CO 2) uptake and inducing oxidative stress. This study explored the potential application of MgAN in the production of algal lipids under high CO 2 concentrations. The impact of MgAN (0.05–1.0 g/L) on cell growth, lipid accumulation, and solvent extractability varied among three tested oleaginous Chlorella strains (N113, KR-1, and M082). Among them, only KR-1 exhibited significant improvement in both total lipid content (379.4 mg/g cell) and hexane lipid extraction efficiency (54.5%) in the presence of MgAN compared to those of controls (320.3 mg/g cell and 46.1%, respectively). This improvement was attributed to the increased biosynthesis of triacylglycerols and a thinner cell wall based on thin-layer chromatography and electronic microscopy, respectively. These findings suggest that using MgAN with robust algal strains can enhance the efficiency of cost-intensive extraction processes while simultaneously increasing the algal lipid content. [ABSTRACT FROM AUTHOR]