Sprirulina extract enrich in phenolic antioxidants may provide a promising source of natural antioxidant. Thus, crude organic extracts of S.splatensis possessed strongest free radical scavenging activity. This finding suggests that the presence of electron and/or hydrogen donating constituent in algal organic extracts such as phycocyanin, carotenoid and phenol compounds. However, the positive correlations between phenol, phytosterol and carotenoids contents in Sprirulina and its antioxidant activity is also well documented .Total phenolic, phycocynin, carotenoids and chlorophyll-derived present in the organic extracts might It is worth mentioning that, antioxidant activity of phenol compounds is mainly due to their redox properties, which can play an important role in adsorbing and neutralizer free radical, quenching singlet and triplet oxygen, or decomposing peroxides .Similar antioxidant properties were found for carotenoid compounds that is capable to scavenging of free radicals and quench singlet oxygen primarily by physical mechanism. Это и многое другое вы найдете в книге Therapeutic potential of Spirulina platensis: Beryllium toxicity (Sangeeta Shukla,Purneema Rawat and Sadhana Shrivastava)