A biphasic photobioreactor system for consecutive extraction of lipids and carotenoids from pre-hydrolysed microalgae and evaluation of its biodiesel potential.

A green extraction method is developed using partially hydrolysed microalgal cells grown in biocompatible solvent for simultaneous cultivation and extraction of bioproducts from a highly efficient permeabilized microalgal cell with enhanced biomass and lipid content for potential use in biodiesel production. Incomplete digestion of cell wall was achieved by regulating the incubation time of the enzymatic pretreatment of the microalgal cells. 15.77% increase in lipid content was seen when untreated cells were cultured with biocompatible solvent, while cultivation of these enzymatically pretreated cells with biocompatible solvent, the lipid content increased by 53.33% and 22% higher carotenoid content was observed as compared to conventional extraction. The total fatty acids obtained after 1st and 2nd extractions in untreated samples were 67.82%, while those in enzymatically partially digested samples were 91.94%. The untreated and partially enzymatically predigested strain showed suitable properties for quality biodiesel production as per international recommendations. The cost benefit analysis of the overall process showed the use of biocompatible solvent coupled to enzymatically predigested biomass was a favorable option as compared to conventional extraction. [Display omitted] • Non-destructive green method using dodecane in enhanced permeabilized algal cell. • Simultaneous cultivation and extraction using biocompatible solvent dodecane. • Consecutive recovery of lipids and carotenoids from single biomass in biphasic PBR. • Recovery using wet biomass and scalable method for a profitable enterprise. • Suitable for quality biodiesel production with higher lipid and carotenoid content. Synopsis Statement A green extraction method using partially hydrolysed microalgal cells grown in biocompatible solvent is evaluated for cultivation in PBR with enhanced lipid content as potential biodiesel feedstock. [ABSTRACT FROM AUTHOR]