Table 4.

Description of the methods of purification used to improve the purity of phycocyanin recovered from Spirulina, the conditions used, and the values of purity and recovery obtained by each method.

Purification Method	Conditions	Purity *	Recovery (%)	Ref.
Ammonium sulfate (AS) precipitation	50–65% AS	2.11	86	[197]
Chitosan and activated charcoal	0.24% chitosan/8.4% activated charcoal	3.14	79	[198]
Stirred fluidized bed IEC	1%, dw/v in STREAMLINE DEAE 10%, dw/v in STREAMLINE DEAE	2.70 3.00	90 64	[199]
IEC	IEC with pH gradient using an anion-exchanger Q-Sepharose Fast Flow column	4.20	49	[200]
Combined methods	50–65% AS, dialysis in sodium acetate buffer, IEC on a DEAE-Sepharose Fast Flow column	5.59	67	[197]
	50% AS, dialysis, ultrafiltration with MWCO of 50 kDa and IEC (anion-exchanger resin Q-Sepharose Fast Flow column) with pH gradient	4.00	80	[44]
	65% AS, 65% dialysis with 12–14 kDa membranes, microfiltration, IEC in a Sephadex-G-100 column, and HPLC with a reverse column	92%	53	[88]
	1.113 M AS, filtration with a PVDF membrane and two hydrophobic interaction membrane chromatography steps	4.20	67	[201]
	2% w/v chitosan solution, 80 g/L activated charcoal, ultrafiltration, and IEC on DEAE Sephadex A-25	4.30	42	[151]

AS: ammonium sulfate, IEC: ion exchange chromatography, DEAE: diethylaminoethyl, HPLC: high performance liquid chromatography, MWCO: molecular weight cut-off, PVDF: polyvinylidene fluoride. * Phycocyanin purity index: A615-620/A280 > 0.7—food grade; >1.5—cosmetic grade, >3.9—reagent grade, >4.0—analytical grade [41].