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Molecular biology

Phycocyanin

The blue spirulina pigment that scavenges free radicals and calms inflammation

Definition

Phycocyanin is a deep-blue, water-soluble phycobiliprotein found in spirulina (Arthrospira platensis) and other cyanobacteria, where it acts as a light-harvesting pigment for photosynthesis. It makes up as much as 15-20% of spirulina's dry weight and is responsible for its blue-green hue. In the human body it functions as a potent antioxidant and anti-inflammatory: it neutralizes peroxyl, hydroxyl and peroxynitrite radicals and inhibits the NF-κB inflammatory pathway. It is one of the most extensively studied bioactive compounds in spirulina.

Detailed explanation

Phycocyanin consists of an apoprotein covalently bound to a linear tetrapyrrole chromophore called phycocyanobilin, structurally related to bilirubin — which underlies its radical-scavenging capacity. Studies published in Biochemical and Biophysical Research Communications show it is a potent peroxyl-radical scavenger both in vitro and in vivo, reducing lipid peroxidation in models of liver injury.

Its anti-inflammatory mechanism centers on inhibition of cyclooxygenase-2 (COX-2) and modulation of the NF-κB pathway, with documented reductions in pro-inflammatory cytokines across multiple experimental models of inflammation. It also activates the Nrf2/HO-1 axis, a master regulator of cellular antioxidant defense that overlaps with the targets of other carotenoids such as astaxanthin.

Reviews of the medical applications of phycocyanin describe hepatoprotective, neuroprotective and immunomodulatory effects, with a favorable safety profile in in vivo toxicity studies. In longevity protocols its antioxidant action is leveraged as part of addressing oxidative stress and inflammaging, typically via spirulina consumption or standardized phycocyanin extracts.

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LongevityMap content is for informational and educational purposes only. It does not constitute personalised medical advice. Always consult a healthcare professional before starting any treatment. Our team · Methodology