Effect of three sources of nutrients on biomass and pigment production of freshwater microalgae Hyaloraphidium contortum

Abstract

Multifunctionality of microalgae is becoming increasingly important, hence science develops new techniques to maximize their potential by providing food, sustainable and affordable fuels and innovative environmental solutions. In this study, we analyzed the effect of different nutrient sources (Nitrofoska®, Quimifol® and Guillard) and sowing time on the kinetics of growth and pigment production of freshwater microalgae Hyaloraphidium contortum; besides of registering some physical and chemical variables in different growth means. Bioassays were performed in batch cultures by quadruplicate, maintaining and continuously controlling temperature, ventilation and lighting. Growth was determined by cell count and production of pigments by spectrophotometry. The largest population densities and productivities per volume of culture were obtained in f/2 Guillard (9.7±0,2x10⁷ cel/ml and 7,6x10⁸ cel/l/día) and Nitrofoska® (8.7±0,5x10⁷ cel mL^-1 and 5.7x10⁸ cel/l/día). The highest average chlorophyll a, chlorophyll b and total carotenoid concentration was achieved with foliar fertilizer Nitrofoska®, on days 18 and 24 (8, 3.29 and 2.2 μg mL, respectively), followed by the obtained by Guillard and Quimifol®. We conclude that this microalgae can be grown with commercial agricultural fertilizers as an alternative source of nutrients to produce biomass and pigments with applications in biotechnology and aquaculture industries.