“…The positive control was Rhodococcus rhodochrous strain DAP 96253 grown on yeast extract (10 g) malt extract (10 g) agar (20 g) (YEMEA) supplemented with cobalt (100 p.p.m. ), urea (7.5 g), and glucose (4 g) for 7 days at 30 C (Tucker et al, 2012;Dietz & Thayer, 1980). Cells were combined with 2 ml of saponification reagent (200 g KOH, 400 ml deionized water and 400 ml methanol) and mixed for 30 s, then autoclaved for 80 min at 121 C. The cooled mixture was combined with 1.5 ml of acidification reagent (6 M HCl) and shaken for 30 s. Mycolates were extracted twice with 2 ml dichloromethane (DCM).…”