EFFECTS OF NITROGEN AND PHOSPHORUS ON BIOCHEMICAL COMPOSITION OF MICROALGAE POLYCULTURE HARVESTD

TÍTULO

EFFECTS OF NITROGEN AND PHOSPHORUS ON BIOCHEMICAL COMPOSITION OF MICROALGAE POLYCULTURE HARVESTD FROM PHYCOREMEDIATION OF PIGGERY WASTEWATER DIGESTATE

DOCUMENTO - ARTIGO CIENTÍFICO  

AUTORES - WILLIAM MICHELON, MARCIO LUIS BUSI DA SILVA, MELISSA PAOLA MEZZARI, MATEUS PIROLLI, JEAN MICHEL PRANDINI, HUGO MOREIRA SOARES

RESUMO/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.

Profissionais, estudantes e interessados na cadeia do biogás e, atuantes nas diversas áreas, etapas de projetos ou operação na produção de biogás.