Comparative lipidomic analysis of Chlorella stigmatophora and Hemiselmis cf. andersenii in response to nitrogen-induced changes

authors	Fernandes, T; Ferreira, A; Cordeiro, N
nationality	International
journal	ALGAL RESEARCH-BIOMASS BIOFUELS AND BIOPRODUCTS
author keywords	Nitrogen supplementation; Hemiselmis cf; andersenii; Chlorella stigmatophora; Lipidome analysis; Nutraceutical lipids
keywords	MARINE MICROALGAE; FATTY-ACIDS; STERYL GLYCOSIDES; GROWTH; BIOSYNTHESIS; SALINA; PLANTS; ALGAE; CELL
abstract	The current focus of algae biotechnology is the production of high-value lipids, and its improvement by employing abiotic perturbations such as nitrogen-induced changes. In the present study, the growth dynamics, nitrogen uptake, pigments, and lipid composition of Chlorellla stigmatophora and Hemiselmis cf. andersenii were studied, in response to low (LN), medium (MN) and high (HN) nitrogen supplementations. Both microalgae responded to increased nitrogen levels by increasing their nitrogen uptake rate and pigment content. However, for lipid accumulation, C. stigmatophora presented a different pattern (LN: 16.56% > MN: 11.51% > HN: 10.95%) to that of H. cf. andersenii (MN: 15.37% > HN: 13.06% > LN: 6.71%). Untargeted gas chromatography-mass spectrometry analysis allowed the visualization of the biochemical diversity of C. stigmatophora and H. cf. andersenii, as well as differences in lipid regulation upon nitrogen-induced changes among species. For instance, glycosyl sterols were only detected for C. stigmatophora samples grown under MN and HN conditions. Moreover, lipid analysis of H. cf. andersenii, before and after alkaline hydrolysis, suggests that wax esters play a key role in the response of this microalga to high nitrogen levels. The cultivation of H. cf. andersenii at MN and HN was shown to be ideal for providing a rich source of omega 3 and polyunsaturated fatty acids for nutraceutical purposes. The hierarchical cluster analysis showed the differential intra- and interspecific effects of nitrogen on lipid composition. The diverse ways by which both microalgae responded to nitrogen-induced changes highlighted the influence of phylogeny on the carbon flux through metabolic networks, and accumulation.
publisher	ELSEVIER
issn	2211-9264
year published	2021
volume	58
digital object identifier (doi)	10.1016/j.algal.2021.102417
web of science category	12
subject category	Biotechnology & Applied Microbiology
unique article identifier	WOS:000686735100012