Effects of nitrogen and phosphorus on biochemical composition of microalgae polyculture harvested from phycoremediation of piggery wastewater digestate.

• Autor(a) principal: MICHELON, W.
• Data de Publicação: 2016
• Outros Autores: SILVA, M. L. B. da, MEZZARI, M. P., PIROLLI, M., PRANDINI, J. M., SOARES, H. M.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da EMBRAPA (Repository Open Access to Scientific Information from EMBRAPA - Alice)
• Texto Completo: http://www.alice.cnptia.embrapa.br/alice/handle/doc/1111098
• topic: Swine wastewater; Phycoremediation; Suíno; Microalga; Águas Residuais; Carbohydrates; Lipids; Microalgae

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 %&#8201;±&#8201;0.5 to 16.3 %&#8201;±&#8201;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&#8201;<&#8201;0.01) as compared to centrifugation.