Fig. 4

a Artificial biofilm obtained by inoculating three cyanobacteria isolates on agar. b After the growth, the biofilm was cut into representative pieces all around the same size and with similar biofilm coverage to test the effect of different essential oils concentrations. c Biofilm samples used as controls and biofilm samples treated with emulsified EOs at 0.1% (d), 1% (e), 10% (f). After the treatment, there was an evident reduction in pigment content, proportional to the EOs concentration