Batch and continuous culture experiments on nutrient limitations and temperature effects in the marine alga Tetraselmis suecica

Abstract

Batch growth and chemostat culture experiments were carried out with the marine alga Tetraselmis suecica (Kylin), a unicellular alga which is potentially useful for wastewater treatment by controlled eutrophication. In natural (Mediterranean coastal) seawater enriched with nutrients, at 22°C, under illumination at 12 h 12 h light/dark, with an intensity of 500 ft-candles, the maximal specific growth rate was μ max = 0.61 day −1 (base e), measured both in batch and in chemostat experiments. Cell population densities were determined as a function of temperature at fixed dilution rates. The optimal growth temperature was between 25 and 27°C. With an abundant supply of nutrients, it was possible to sustain substantial population densities in the temperature range of 15–32°C.