Author(s): MICHELON, W.; SILVA, M. L. B. da; MEZZARI, M. P.; PIROLLI, M.; PRANDINI, J. M.; SOARES, H. M.

Summary: Abstract: The effects of nitrogen (N) and/or phosphorus (P) starvation on the biochemical composition of native microalgae Chlorella spp. polyculture obtained from the phycoremediation of swine wastewaters were investigated. Microalgae-specific growth rate of 1.2 day(-1) was achieved (30.3 mg L(-1) day(-1)). PO4 (-2) and NH3 were completely removed from swine digestate effluent after 3 and 11 days, respectively. Microalgae harvested immediately after nutrient removal showed high protein (56-59 %) and carbohydrate (25-34 %) but low lipid (1.8-3 %) contents. Depletion of N or P alone stimulated carbohydrate production at the expenses of proteins. Significant lipid accumulation from 3 % ± 0.5 to 16.3 % ± 0.8 was reached only after 25 days following N and P starvation as demonstrated by Nile red-stained cells. Regarding to the effects of harvesting methods on cellular biochemical composition, circumstantial evidences indicate that coagulation-flocculation with tannin may lead to lower protein and lipid amounts but increased carbohydrate content (p < 0.01) as compared to centrifugation.

Publication year: 2016

Types of publication: Journal article

Unit: Embrapa Swine & Poultry

Keywords: Carbohydrates, Lipids, Microalga, Microalgae, Phycoremediation, Suíno, Swine wastewater, Águas Residuais