2.1.2.2. Ability to reduce CH4 emissions. The PNSB strains that
passed our primary screening were also tested for their ability to
reduce CH4 emissions by following the method of Harada et al.
(2003). The PNSB strains were grown as described above for the
inoculum to obtain culture broths. Each culture broth was
centrifuged at 4307 g for 15 min, and its cell pellet was
washed twice with 0.25% NaCl solution. Finally the cell pellet
was suspended in 3 mL of sterile distilled water. The cell
suspension was adjusted to an optical density (OD) of 0.5 at
660 nm, by dilution with 0.25% NaCl solution, for use as the
inoculum. This provided approximately 108 CFUmL1 bacteria.