Optimization of spirulina platensis and natural pigment production by response surfaces production

Spirulina platensis has attracted special attention in various industries due to its natural pigments with specific performance characteristics. In this study, the effects of vitamin B12 (0.5 to 1.5 µg/l), date waste extract as a carbon source (1 to 1.5 g/l of glucose), and urea as a source of nitrogen (50 to 150 mg / l) parameters by fed-batch feeding under submerged culture was optimized and the production of Spirulina platensis and natural pigments were examined. The results showed that the addition of urea and date waste extract increased the production of biomass and phycocyanin, allophycocyanin, carotenoids, and chlorophyll. The results of the effect of vitamin B12 showed that this vitamin in low concentration has a positive effect on the production of spirulina and the pigments phycocyanin, allophycocyanin, carotenoids, and chlorophyll. Also, the use of date waste extract with vitamin B12 should be used optimally in combination with each other to achieve the highest production efficiency of biomass and pigments phycocyanin, allophycocyanin, carotenoids, and chlorophyll. At low concentrations of vitamin B12, increasing changes in date waste increase carotenoid production. Also, in low concentrations of date waste, with increasing changes in vitamin B12, carotenoid production increases, but in the highest concentration of these two variables, carotenoid production decreases due to the opposite effect. In high concentrations of vitamin B12, increasing changes in urea increase chlorophyll production. At the optimized condition, (vitamin B12 0.5 µg.l-1, date waste extract 1.5 g.l-1 of glucose, urea 150 mg.l-1) the biomass, phycocyanin, allophycocyanin, carotenoids and chlorophyll contents were 203 (g/100g) 128, 8.42,  4.09 and 7.2  (mg.l-1). It can be concluded that vitamin B12 along with the use of date waste creates mixotrophic conditions in the growth of Spirulina platensis, which leads to increased production of biomass and natural pigments.