The antimicrobial activity of the essential oil was determined by
the standard agar disk diffusion method (Mahboubi, & Haghi,
2008). A 0.5 McFarland (1 107–1 108 CFU/mL) concentration
of bacterial suspension was uniformly inoculated on Mueller
Hinton agar (MHA) solidified in 120 mm Petri dishes. Once the
dishes were prepared, 6 mm-diameter discs of filter paper containing
10 lL of the essential oil, which had been diluted ten times
with dimethyl sulfoxide (DMSO), were pressed gently against the
surface of the agar. Discs containing an isoconcentration of pure
allyl isothiocyanate were used as positive controls, while the sol-
Fig. 1. The chemical structures of Genipin and Geniposide. vents dichloromethane and DMSO were used as negative controls