Evaluation of carbon capture in competent microalgal consortium for enhanced biomass, lipid, and carbohydrate production.

Enrichment of carbon dioxide (CO2) in environment is a major factor for enhancement of global warming on Earth surface. Microalgal consortia play an important role in inhibiting the alarming fluxes of CO2 through sustainable mechanism of bioconversion of CO2 into biomass. In the present investigation, eight heterogeneous consortia of cyanobacteria and green algae such as MC1, MC2, MC3, MC4, MC5, MC6, MC7, and MC8 for the sustainable utilization of effective CO2 sequestration and biomass production were studied. Two factorial central composite designs (% CO2 and pH) were used for optimization of cellular morphology, growth, and development of consortia. The photosynthetic quantum yield of consortium MC8 was found to be maximum (0.61) in comparison with other consortia. The morphological and physiological behavior of the above consortium was analyzed under C, 5, 10, and 15% concentrations of CO2 resource capture in 250 mL BG-11+ medium. We have identified that 10% CO2 concentrated medium maximally promoted the cellular growth in terms of cell dimension, dried biomass, carbohydrate, and lipid contents in this consortium. As such, the elemental composition of carbon and carbon capturing capability was high at 10% CO2 concentration. However, further CO2 enrichment (15%) led to decline in growth and morphology of cell size as compared to control. The results indicate that the optimum CO2 enrichment in consortia exhibits potent commercial utilization for rapid biomass production and plays a distinguished role in global carbon sequestration and mitigation agent. © King Abdulaziz City for Science and Technology 2019.