Inhibition of S. aureus
agr
lux reporter with H. canadensis leaf extract. An S. aureus
lux reporter strain was used that responds to exogenous AIP-1. A constant level of AIP-1 was mixed with extract, incubated with the lux reporter, and bioluminescence was measured. The extract was standardized to berberine and added to a concentration range of 10–80 µg/mL. AIP-2, a known inhibitor, was used as positive control. Values reported represent means of quadruplicate assay wells, with error bars representing the standard deviation of the mean, and * indicates p <0.0001 compared to vehicle (calculated with a two-tailed student’s t-test).