Ez anaerobe chamber

Extracts were first tested against a C. acnes isolate obtained from the American Type Culture Collection (strain ATCC6919). Based on these results, the most active fractions and their parent extracts were tested for growth inhibitory activity in nine additional clinical isolates of C. acnes; strain and source details are provided in Table 3. All bacteria were streaked onto tryptic soy agar (TSA) plates supplemented with 5% sheep blood (Hardy). Plates were incubated at 37°C until individual colonies were visible (72 h for most isolates and 120 h for the slowest growers) before individual colonies were transferred into Brain Heart Infusion broth supplemented with 1% dextrose (BHId). Liquid cultures were incubated for an additional 72 h before preparation of a working culture for biological assays. An EZ Anaerobe Chamber and GasPak EZ Anaerobe (BD) container sachets were used to create the anaerobic conditions required for C. acnes growth.

The P. acnes isolate was obtained from the American Type Culture Collection (ATCC® 6919™). The strain was streaked from freezer stock onto Tryptic soy agar plates (TSA) supplemented with 5% sheep blood (BD, Franklin Lakes, NJ) and incubated at 37°C for 72 h prior to making liquid cultures in brain heart infusion (BHI) broth (BD, Franklin Lakes, NJ) supplemented with 1% dextrose (Fisher Scientific, Waltham, MA) (additional 72 h incubation) for use in the below described assays. All cultures were grown in anaerobic chambers using the EZ Anaerobe Chamber (BD, Franklin Lakes, NJ) and GasPak EZ Anaerobe container sachets (BD, Franklin Lakes, NJ).