Preliminary Studies Demonstrating Acetoclastic Methanogenesis in a Rat Colonic Ring Model

Table 3

Bacterial counts, lactate, and acetate concentrations in rat colonic ring preparations.

Assayed system	Concentrations
	1 hour; (𝑁=3, mean ± SD)	24 hours; (𝑁=3, mean ± SD)
Bacterial counts^a
Tissue	4.0 ± 0.4 × 10^5	5.0 ± 5.0 × 10^9
Media	5.0 ± 0.5 × 10^5	6.0 ± 6.0 × 10^9
Lactate^b	20.0 ± 1.0	3.0 ± 1.0
Acetate^b	5.0 ± 1.0	693 ± 1.5

aWashed rat colonic rings were incubated at the times indicated, as described in Methods.
Bacterial counts expressed as counts per gram of tissue or per 10 mL of media.
^bLactate or acetate concentrations were determined in the media, as described in Methods, and are expressed in mg/liter of media. The results are the average of three experiments, mean ± SD, with six rats in each experiment.