Antioxidant activity of supercritical extracts from Nannochloropsis gaditana: Correlation with its content of carotenoids and tocopherols

•Minor lipids content and antioxidant activity were studied under a response surface design.•High temperature and CO2 density resulted in higher minor lipids content and antioxidant activity.•Extraction temperature had an effect higher than CO2 density on studied responses.•Antioxidant activity positively correlated with the minor lipids content in microalga oil.•Fatty acid composition was measured in selected supercritical extract from Nannochloropsis gaditana.•No previous studies have reported on supercritical extraction from pelletized microalgae.