Research Article

The Effect of Saturated Fatty Acids on Methanogenesis and Cell Viability of Methanobrevibacter ruminantium

Table 2

Methane inhibition rate, K+ efflux, and cell viability in cell suspensions treated with different saturated fatty acids at 10 μg/mL in Experiment ( ; means ± standard error).

Time3 h24 h
TreatmentK+(mg/L)CH4 inhibition rate (%)1Cell viability (%)2K+  (mg/L)CH4 inhibition rate (%)1Cell viability (%)2

Blank5.1 ± 0.1d−6.8 ± 3.5b79 ± 7a14.2 ± 0.3b−2.5 ± 11.1b50 ± 8a
Control5.4 ± 0.4db81 ± 2a12.9 ± 0.3bb40 ± 6a
C1213.8 ± 0.2a99.9 ± 0.0a43 ± 2b15.7 ± 0.2a100 ± 0.1a1 ± 0b
C1413.9 ± 0.2a99.8 ± 0.2a36 ± 5b15.7 ± 0.3a100 ± 0.0a3 ± 1b
C168.7 ± 0.2b85.4 ± 1.8a68 ± 6a13.5 ± 0.1b100 ± 0.1a12 ± 5b
C187.0 ± 0.1c7.9 ± 17.6b78 ± 5a13.9 ± 0.2b44 ± 16.2ab38 ± 5a
P values<0.0001<0.0001<0.0001<0.00010.0015<0.0001

Treatment means with unequal superscripts are different at P < 0.05.
1Calculated from methane production rate (μmol/mg cell DM/min) in percent of the value of the control group after 3 and 24 h, respectively.
2Percentage of live cells (green) of total cells (green, yellow, and red) as determined with the LIVE/DEAD BacLight Kit.