Interaction of photoperiods and light intensities on population growth and biochemical composition of marine diatom Thalassiosira weissflogii (Grunow) G. Fryxell & Hasle, 1977
Abstract
The study was conducted to investigate the interactive effects between light intensity and photoperiod on the growth of populations and biochemical composition of marine diatom, Thalassiosira weissflogii. In this research, T. weissflogii was cultured in 9 experimental conditions, representing a full factorial design of 3 light intensities at three different levels of 75, 100, and 125 µmol/m/s (µE/m2/s) and three photoperiods of 12 hours light: 12 hours dark (12hL:12hD), 16 hours light: 8 hours dark (16hL:8hD), and continuous light for 24 hours (24hL:0hD). Population growth parameters (maximum cell density, exponential growth rate) and the biochemical composition of microalgal were collected. The study results revealed a strong interaction between light intensity and photoperiod, significantly regulating the growth of T. weissflogii population. The average light intensities and photoperiod (100-125 µE/m2/s and 18hL:6hD) resulted a high productivity in the culture of T. weissflogii. The high light intensities and photoperiods resulted the increasing accumulation of SFAs and MUFAs, as well as decreased the levels of EPA and DHA in specific cases.
