Strategies for improved production of phycobiliproteins (PBPs) by Oscillatoria sp. BTA170 and evaluation of its thermodynamic and kinetic stability

In the present study, cyanobacterium BTA 170 was isolated from Manipur, India and was phylogenetically related to Oscillatoria sp. The biomass of BTA 170 contained 6.5% of ash, 32.25% of carbohydrate, 37.44% of protein, 22.31% of lipid and 1.5% of moisture. 0.3 M of glycine and 5 mM of sodium glutamate were required for BTA 170 as supplements in BG 11 media for maximum yield of cell biomass and PBPs production. However, 6k Lux of light intensity and 14:10 (Light: Dark) of photoperiod were found as optimum for higher productivity. The specific growth rate was found to be 0.228 day(-1) and production of PBPs was found to be growth associated. The first-order kinetic model was used to investigate the deactivation process of PBPs and the deactivation rate constant (kd) was found to be minimum in the temperature range from 10 to 40 degrees C and pH 7. The maximum deactivation of PBPs was found at pH 12 and 80 degrees C. Gibb's free energy for PE, PC and APC were found to be 109.38-117.34; 108.10-115.21 and 108.74-116.48 kJ/mol respectively at pH 7. The pH and thermal tolerances of PBPs suggested that they may have potential for use as pigments in industry.