The methanol extracts of the two microalgae showed higher content of phenolic compounds (EMS = 2.62 mg/g; EMC = 0.69 mg/g) compared to ethanol extracts (EES = 1.37 mg/g; EEC = 0.41 mg/g), with the values being significantly higher (p ≤ 0.05) for Spirulina. The results showed that the greater polar solvent (methanol) contributed to extract higher concentrations of phenolic compounds for both microalgae studied. It is known that phenolic compounds, particularly phenolic acids, are mostly found in extracts of higher polarity [26], besides the possibility to also find pigments such as phycocya- nine and sulfated polysaccharides [27], which may con- tribute to increase the antioxidant activity [28]. The val ues found for the extracts of Spirulina in this study were higher than those of Souza et al. [23] who obtained 1.15 mg gallic acid.g−1 for methanol extracts of microalgae Spirulina platensis. Cepoi et al. [29] evaluated the influ- ence of ethanol concentration of the solvent for the ex- traction of phenolic compounds from Spirulina platensis and Nostoc linckia, and concluded that the highest con- centration of ethanol (70%) did not provide greater ex- traction of phenolic compounds from Spirulina, and that a concentration of 55:50 (ethanol:water) did. However, for the microalga Nostoc, the higher content of phenolic compounds was obtained in the highest concentration of ethanolic solvent. Manivannan et al. [30] evaluated the effect of the solvents methanol, diethyl ether and hexane for extraction of phenolic compounds from Chlorella