Fig. 3From: Ultrasound-assisted extraction of bioactive pigments from Spirulina platensis in natural deep eutectic solventsResponse surface and contour plots representative of the interaction effects of (a, b) time and solvent-to-biomass ratio; (c, d) temperature and solvent-to-biomass ratio; (e, f) time and temperature on the total phenolic content (TPC)Back to article page