Enhanced biomass and lipid production of Neochloris oleoabundans under high light conditions by anisotropic nature of light-splitting CaCO3 crystal

• Published in: Bioresource technology Vol. 287; p. 121483
• Main Authors: Hong, Min Eui, Yu, Byung Sun, Patel, Anil Kumar, Choi, Hong Il, Song, Sojin, Sung, Young Joon, Chang, Won Seok, Sim, Sang Jun
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.09.2019
• Subjects: Anisotropic CaCO3 crystal; CaCO3 biomineralization; Mild calcification method; Multiple light-splitting effect; Neochloris oleoabundans; Anisotropic CaCO3 crystal; Multiple light-splitting effect; Mild calcification method; Neochloris oleoabundans; CaCO3 biomineralization
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2019.121483

[Display omitted] •CaCO3 crystal(CN)-coating much improve the microalgal biomass and lipid production.•CN-coating is carried out at mild alkali pH, CaCl2 under N-starvation in microalgae.•Autotroph Neochloris show superior CaCO3 crystallization after 6 days of induction.•Photosynthesis is augmented by anisotropic CN-driven light splitting at high light.•Separated biogenic CaCO3 crystal could be highly beneficial in microalgal industry. The aim of this work was to study the anisotropic effect of crystalline CaCO3 nanoparticles (CN)-driven multiple refraction/scattering from the CN-coated agglomerated cells on the rate of photosynthesis and the product yield under high light conditions in the freshwater microalgae Neochloris oleoabundans. The CN-coating via biomineralization significantly improved the biomass and lipid production of N. oleoabundans during second stage of autotrophic induction by sustaining relatively high rate of photosynthesis at high irradiance using the multiple-splitting effect of the anisotropic polymorphism. The CN were successfully produced, adsorbed and grown on the external cells under conditions of mild alkalinity (pH 7.5–8.0), mild CaCl2 concentration (0.05 M) and under nitrogen starvation with strong light (400 µE m−2 s−1). Consequently, lipid content and productivity of N. oleoabundans cells cultured with 0.05 M CaCl2 increased by 18.4% and 31.5%, respectively, compared to the cells cultured with 0.05 M CaCl2 and acetazolamide to inhibit calcification.