M. tuberculosis culture - M. tuberculosis culture
Three 10ml cultures of M. tuberculosis H37Rv were grown at 37C in Middlebrook 7H9 broth (Difco) plus 10% (vol/vol) oleic acid-albumin-dextrose-catalase 2 (OADC) supplement (Becton Dickinson) and 0.05% (wt/vol) Tween 80. After 7 days the cultures were combined and OD taken. Four 100 ml volume 7H9 cultures were inoculated with 3 ml 7 day culture (passage 2-5, O.D approx 0.3), and incubated with stirring at 280 rpm using 40x8 mm stir bars for 4 days (ensuring screw top to 250 ml Duran bottle was loose enough to allow air exchange). O.D/CFU readings were taken from cultures (from day 4 to day 6) to ensure bacilli were in log-phase. Blood agar plates were set up on day 0 and day 4 to test for contamination.