Fig. 2

Light microscopy assay. Effect of essential oils (EO) on inhibition of biofilm formation (growth and development); Escherichia coli, A1 bacteria supplemented with EO of cinnamon at MIC (high activity), B1 bacteria supplemented with Ci/Ca EOs combination MIC (poor activity), C1 positive control (bacteria supplemented with antibiotic MIC), D1 negative control (non-treated slides). Bacillus subtilis, A2 bacteria supplemented with EO of cinnamon/cardamom combination at MIC (high activity), B2 bacteria supplemented with CaEO at MIC (poor activity), C2 positive control (bacteria supplemented with antibiotic MIC), D2 negative control (non-treated slides)