Journal: Journal of Veterinary Diagnostic Investigation : Official Publication of the American Association of Veterinary Laboratory Diagnosticians, Inc
Article Title: Improved detection of Mycobacterium tuberculosis and M. bovis in African wildlife samples using cationic peptide decontamination and mycobacterial culture supplementation
doi: 10.1177/10406387211044192
Figure Lengend Snippet: Conventional Bactec MGIT (MGIT tube containing PANTA-OADC antimicrobial enrichment media) and TiKa (MGIT tube containing PANTA-OADC and TiKa supplement B) culture results represented as median time to positivity (d) with interquartile ranges (IQR) for sterile phosphate buffer spiked in duplicate with known amounts (cfu) of A. Mycobacterium bovis SB0121 (10,000–10 cfu) and B. M. tuberculosis H37Rv (10,000–10 cfu), respectively. Prior to inoculation into growth indicator tubes, all spiked samples were either: decontaminated with MycoPrep (treatment 1: MycoPrep MGIT; treatment 2: MycoPrep TiKa), not decontaminated (treatment 3: MGIT control; treatment 4: TiKa control), or decontaminated with KiC agent (treatment 5: KiC MGIT; treatment 6: KiC TiKa). For some data points, the IQRs were shorter than the height of the bar; in these cases, the ranges were not drawn. Using the multiple t -test with Bonferroni–Dunn correction for multiple testing (alpha = 0.01), statistical significance ( p < 0.01) was calculated between treatments for each amount of mycobacteria. Within each amount of the target Mycobacterium , bars with a different superscript are significantly different at p < 0.01.
Article Snippet: M. bovis SB0121 and M. tuberculosis H37Rv stock cultures (Stellenbosch University) were subcultured in separate T25 culture flasks (Thermo Fisher) containing 5 mL of liquid Middlebrook 7H9 broth medium (Merck), 0.05% Tween 80 (Merck), 0.2% glycerol, and 10% Middlebrook oleic acid dextrose citrate (OADC) growth supplement (Merck) at 37°C for 5 d. The optical density (OD) was determined, and cultures diluted to an OD = 0.05 in 30 mL of 7H9 culture medium in T75 culture flasks.
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