Table 2.

The inhibition activity of sub-MIC levels of plant extracts against biofilm formation of PS-1

Sub-MIC Levels	Plant extracts (MIC)
	Cinnamon (6.25 mg/ml)	Clove (6.25 mg/ml)	Thyme (6.25 mg/ml)	Rosemary (12.5 mg/ml)	Peppermint (12.5 mg/ml)	Pomegranate (6.25 mg/ml)	Ginger (12.5 mg/ml)
	Biofilm inhibition mean %1 ± SD
0.5× MIC	64.00 ± 0.12a	67.41 ± 0.02d	59.37 ± 0.02e	90.83 ± 0.01g	85.47 ± 0.01i	91.93 ± 0.01g	71.56 ± 0.01h
0.25× MIC	54.47 ± 0.57b	61.00 ± 0.06e	48.10 ± 0.02f	72.33 ± 0.01h	71.23 ± 0.57h	72.30 ± 0.14h	64.30 ± 0.01a
0.125× MC	50.70 ± 0.14c	50.87 ± 0.07c	47.43 ± 0.01f	72.33 ± 0.02h	48.50 ± 0.13f	64.63 ± 0.06a	51.70 ± 0.08c

1: The inhibition % calculated from biofilm control (untreated with plant extract); SD, standard deviation. Statistical analysis was performed using two-way ANOVA and Tukey’s test (P < 0.05); different small letters represent the significant between means of the percentage of biofilm inhibition. The maximum biofilm inhibition activity shown in bold letters