# Antioxidant and Erythroprotective Effects of C-Phycocyanin from the Cyanobacterium Spirulina sp. in Attenuating Oxidative Stress Induced by Peroxyl Radicals

## TL;DR

This study shows that C-phycocyanin from Spirulina can reduce oxidative stress in blood, with varying effects across different blood types.

## Contribution

The study evaluates the erythroprotective and antioxidant effects of C-phycocyanin after in vitro digestion across different blood groups.

## Key findings

- C-phycocyanin showed increased antioxidant capacity in all tested assays after digestion.
- In vitro digestion enhanced the erythroprotective effect in most blood groups.
- Blood groups exhibited varying susceptibility to oxidative stress and hemolysis.

## Abstract

Diseases caused by oxidative stress can present different susceptibilities depending on blood typing according to the ABO system and RhD factor, which turn out to be of great clinical importance. The use of antioxidants such as C-phycocyanin (a phycobiliprotein) could be an alternative to mitigate oxidative stress in the blood. Therefore, the objective of this study is to evaluate the antioxidant and erythroprotective activity of C-phycocyanin (C-PC) from Spirulina sp. against oxidative stress caused by peroxyl radicals, before and after in vitro digestion, comparing susceptibilities between blood groups. C-phycocyanin from Spirulina sp. was obtained commercially. The antioxidant capacity by ABTS+•, DPPH•, and FRAP assays of the bioaccessible fraction of C-PC increased compared to baseline in all assays. Samples appear to have high hydrogen atom transfer. C-PC is not cytotoxic in most blood groups. The AAPH hemolysis assays showed differences between blood groups, yielding results of 27.90, 22.60, 26.94, 27.66, 28.16, 28.34, and 24.91% hemolysis for O+, O−, A+, A−, B+, AB+, and AB−, respectively. Furthermore, in vitro digestion increased the erythroprotective effect in the bioavailable fraction in most blood groups, showing 37.12, 80.13, 5.48, 92.38, 67.93, 80.30, and 76.49% inhibition of hemolysis in O+, O−, A+, A−, B+, AB+, and AB−, respectively. These results demonstrate the biotechnological and biomedical potential of phycobiliproteins as safe candidates for the development of nutraceuticals and functional foods aimed at preventing oxidative damage.