Development of Chlorella pyrenoidosa EMS mutants with enhanced biomass and lipid content for biofuel production

Abstract

Biodiesel production from microalgae depends on algal biomass production through autotrophic cultivation, and it has a lot of potential as a feasible alternative source of energy. The lethal and mutagenic effects of ethyl methanesulphonate (EMS) are investigated in the present study on the organism Chlorella pyrenoidosa for the generation of paler mutants. The C. pyrenoidosa wild-type strain was treated with 0.1, 0.2, and 0.5 M EMS doses and the colonies that appeared after 20 days of growth on a solid TAP medium were analyzed, and a total of two mutant colonies with less pigmentation were identified. The CPM1 (10.02 ± 0.03 and 3.12 ± 0.04 µg/ml) and CPM2 (9.55 ± 0.0 and 32.84 ± 0.03 µg/ml) mutants had lower chlorophyll a and b and carotenoids content than wild type. Mutants produced significant biomass (1.34- and 1.31-fold enhanced biomass in CPM1 and CPM2) and lipid content than the wild type. These findings suggest that genetic modification of C. pyrenoidosa has the potential to produce strains with increased biomass productivity and lipid content for biofuel production.