Mass production of Tetraselmis suecica (Kylin) Butch. (Prasinophyceae), under different concentrations of nutrients and additions of carbon dioxide

Abstract

A series of four experiments with Tetraselmis suecica was carried out under laboratory conditions in order to learn the production yield in volumes of 1,000 litres, with salinity of 28‰, with absence and addition of buffer and carbon dioxide, air flow of 25 I/min and average time of addition of carbon dioxide of two and a half minutes, at a  pressure of 50 kg/cm² to keep the pH equal to or below 7.5. A maximum density of 508,000 cells/ml was obtained with a ratio of 150/10 g/l of NaN0₃/NaH₂P0₄, with an average constant of growth of 0.35 and 0.50 doublings per day. With a quarter and with half of the nutrients without buffer, a higher constant of growth was recorded, although it did not differ significantly at 95% confidence in relation to the control experiment. Productivity per unit of culture volume of T. suecica showed that on using low concentrations of nutrients plus carbon dioxide, good population yields relative to the control are obtained. Productivity was not affected by temperature since it was kept constant at 19 + 1ºC, but it decreases when the supplement of carbon dioxide is insufficient to keep the pH between 7.2-7.5.