Determination of growth and protein ratio of Spirulina platensis cultured under nitrogen and phosphorus deficiency in different coloured LED light sources

The study was carried out to determine the effect of nitrogen and phosphorus limitation (50% N and 50% P reduction) on chlorophyll a, dry matter, optical density and protein ratios of Spirulina platensis cultivated in the laboratory under different coloured (red, green, blue and white) LED light sources. It was determined that the growth was best in the white light source among the treatment groups. Optical density (OD) values in control groups were 1.554, 1.098, 1.088 and 1.062 in white, blue, green and red light sources, respectively. In nitrogen deficiency groups, good growth was observed in blue and red light sources after white, and in phosphorus deficiency groups, good growth was observed in red light sources after white. Protein ratios were highest in the control groups with 76.59% and lowest with 70.29% in the cultures illuminated with red and blue light sources, respectively. In the nitrogen and phosphorus deficiency groups, the lowest protein ratios of 66.87% and 67.27% were found in the cultures illuminated with blue colour, while they were high and similar in the other groups. Keywords: Spirulina platensis, LED, Nitrogen deficiency, Phosphore deficiency, Protein