Investigations into the growth of Mycobacterium leprae in a medium with palmitic acid under different gaseous environments.

: Low oxygen tension has often been considered important for the growth of Mycobacterium leprae. Palmitic acid has been suggested as the oxidizable substrate for the in vitro cultivation of leprosy bacilli. The combined effects of palmitic acid and various known gas mixtures on the in vitro growth of M. leprae were investigated. When palmitic acid was included in the medium an optimal growth in both liquid and solid media was obtained between 16 to 20 weeks of incubation under gas mixtures containing 2.5 or 5% O2 and 5 or 10% CO2 as well as air. The use of different gas mixtures is tedious, time consuming and laborious. Since the cultures incubated under air gave the same cell yield as obtained when incubated under optimal gas mixtures, air alone can be used for the in vitro cultivation trials of M. leprae when palmitic acid is included in the culture medium.