Optimizing Biomass and Phycobilin Production in Arthrospira platensis Through Carbon Source Variation and Developing a Cost-Effective Purification Method

Arthrospira platensis, commonly known as Spirulina , is an industrially cultivated cyanobacterium due to its high content of phycobiliproteins, mainly phycoerythrin, phycocyanin, and allophycocyanin. In this work, a low-cost strategy for the enhancement of biomass and pigment production, along with the improvement of phycocyanin extraction, is investigated. In this regard, two carbon sources at different dosages were tested for their effect on biomass and phycobilin production. Biomass production was estimated in terms of specific growth rate (SGR), cell count per liter, and increase in dry weight. Phycobilin protein quantification was done through spectrophotometry and gel electrophoresis. The results indicated that the addition of extra carbon sources increased cell proliferation and biomass production. Sodium acetate at 50 mg/L/day significantly increased the biomass, SGR, and phycocyanin production. Glycerol at 1 cc per day enhanced cell proliferation and biomass but did not enhance phycobilin accumulation. The spectrophotometric analysis on 5 mg dry phycocyanin with 10 cc distilled water showed no significant difference (p ≥ 0.05) at 680 nm, while in the absorbance at 620 nm, there is a significant difference between spray and oven drying of the samples (p ≤ 0.05).