Fig. 3

Carbohydrate, protein and lipid profiles of P. tricornutum during the two-stage treatment. A Heatmap shows the log2(fold change) values of carbohydrate, protein and lipid contents. B Carbohydrate, protein and lipid contents of day 3 cultures for CT, HL, HLC and HLR. C Microscopic observation of algal cells stained by the fluorescence dye Bodipy. Green fluorescence indicates the Bodipy-bound TAG-filled lipid droplets, while red indicates the plastid autofluorescence (PAF). The significant difference is designated by * (p < 0.05) or ** (p < 0.01) under Student’s t-test