Bioaccumulation and the Effect of Selenate Concentration on Growth and Photosynthetic Pigment Content of Spirulina platensis

Selenium (Se) is a necessary microele-ment for microalgae growth. Moreover, it might be directly act and cause a decrease in primary production in microalgae. Now-adays, there is a great focus on prepara-tions of Se-enriched products. In the current study, the effects of various selenate concen-trations on Spirulina evaluated as a primary stage to large-scale production of Se-en-riched S. platensis. Zarrouk medium sup-plemented to investigate the stimulatory/in-hibitory effects of selenate on the growth at various concentrations. Biomass dry weight and cell mass measured on OD550. Thereaf-ter, inhibitory and algicidal concentrations were determined. Furthermore, its effects on morphology and changes of some important pigments in response to the metal challenge investigated, too. While the results showed that at 5 and 10 ppm concentrations growth was supported, the dry weight of microal-gae decreased at selenate levels above 50 ppm. Besides, the inhibitory and lethal ef-fects of selenate were at 100 ppm and 300 ppm, respectively. In addition, morpholog-ical changes observed at this concentration. Additionally, chlorophyll, carotenoid and phycobiliproteins, showed a stimulatory ef-fect at 5-50 ppm, 10 ppm, and 10 ppm, re-spectively. Moreover, Spirulina uses for foods produc-tion because some chemicals are unique compounds. Simple cultivation method and high quality of its protein, and no toxic ef-fects, cause its feasibility for large-scale production.