The soluble fraction of Solanum tuberosum enhances growth and pigmentation of the microalga Tetraselmis suecica under photoheterotrophic conditions

The soluble fraction of Solanum tuberosum was utilized in the range 0.1–6.2 mg dry weight ml−1 to stimulate photoheterotrophic growth of axenic cultures of the marine microalga Tetraselmis suecica. The concentration of 5.0 mg ml−1 produced the highest cell density, 1.4 × 106 cells ml−1. This was 3.9 and 3.1 times higher than an autotrophic control (0.4 × 106 cells ml−1) and a photoheterotrophic control (0.5 × 106 cells ml−1). Using 3.7 mg dry weight of the S. tuberosum extract ml−1, the microalgae reached the highest contents of chlorophyll and carotenoids, 8.2 and 4.1 times higher than the autotrophic control. The marked enhancement of the photoheterotrophic growth of the microalgae by the addition of potato extract exceeded the growth stimulation caused by glucose and yeast extract. It suggests the feasibility of the use of potato biomass for the production of microalgal biomass and pigments.