Evaluation Of The Growth Kinetics Of Scenedesmus Quadricauda Cultivated In Brewery Wastewater

LOIS-MILEVICICH, J.; ALVAREZ, P.; MATEUCCI R.,; CASA, N.E.; BUSTO, V.; GUTIERREZ, M.C.; GIULIETTI, A.; DE ESCALADA PLA M

Paris

Congreso; AlgaEurope Conference; 2019

EABA

The aim of this study was to evaluate the growth kinetics of Scenedesmus quadricauda, cultivated in a formulated nutrition medium based on brewery wastewater.Three systems were formulated with a Brewery effluent with Chemical Oxygen Demand (COD) of 3000 mgO2/L, containing different salts levels: 1) NaNO3 1.5 g/L, MgSO4.7H2O 0.074 g/L, ammonium ferric citrate 0.0055 g/L; 2) NaNO3 0.75 g/L, MgSO4.7H2O 0.037 g/L, ammonium ferric citrate 0.0055 g/L; 3) ammonium ferric citrate 0.0055 g/L. The systems were inoculated with 10% S. quadricauda, incubated at 26±2°C with 2800 lux light intensity and 100 rpm orbital shaking. Growth was followed by optical density (OD) at 680 nm and by cell count in Neubauer chamber throughout 21 days.The maximal specific growth rate determined by OD was significantly higher for system 3 (1.54±0.09 d-1), although maximal biomass concentration was the lowest for this system (1.98±0.04 g/L). There was no difference between systems 1 and 2 neither in growth rate (1.0±0.1 d-1 and 1.1±0.1 d-1 respectively) nor maximal concentration (2.5±0.1 g/L for both). Same behavior was observed with curves obtained from cell count data. However, cell count brought up significant differences in maximal biomass concentration for all systems.It was found that supplementation with NaNO3 and MgSO4 salts did not improve the growth rate of S. quadricauda, but increased the maximal biomass concentration in the conditions herein assayed. Considering the slight difference observed in maximal cell count, system 2 turns out to be more inexpensive option to continue with further studies.