Spirulina + Chlorella vulgaris as Complementary Nutraceutical Microalgae for Antioxidant, Anti-Inflammatory and Metabolic Support

Abstract

Chronic non-communicable diseases (NCDs) are multifactorial biological processes that develop due to oxidative stress, low-grade inflammation, and metabolic disorders. The bioactive compounds of edible microalgae are considered to have an impact on all three processes. Spirulina (Limnospira platensis) is a filamentous cyanobacterium that is used as a food additive and pharmaceutical raw material. Chlorella vulgaris is a single-celled green algae species that differs from Spirulina in its cellular structure and biochemical composition. The two microalgae are a rich source of protein, carotenoids, polysaccharides, vitamins, minerals, and polyunsaturated fatty acids. They also contain significant amounts of unique compounds: C-phycocyanin, phycocyanobilin, and γ-linolenic acid in spirulina and chlorophyll a and b, lutein, β-carotene, and α-linolenic acid in chlorella. The content of many nutrients depends on the habitat and technology of cultivation, which may explain differences in the literature data. In vitro and animal experiments have demonstrated the ability of spirulina and chlorella to neutralise reactive oxygen species by donating electrons and hydrogen atoms, reduce pro-inflammatory cytokines (TNF-α, IL-6, IL-1β) and the NF-κB transcription factor, increase glucose uptake and insulin sensitivity, and lower cholesterol levels, especially LDL and triglycerides. Studies of the combined use of chlorella and spirulina have revealed a synergistic effect of the two microalgae on the reduction of oxidative stress and inflammation. However, there is no specific clinical evidence for this synergy. The critical evaluation of the available data on the effects of spirulina and chlorella presented in this article shows that these microalgae can be used as a dietary supplement to improve health status and quality of life. However, it cannot be recommended to use them as a method of treating chronic NCDs since the existing evidence is insufficient in terms of the sample size and experimental design.