Preliminary Studies Demonstrating Acetoclastic Methanogenesis in a Rat Colonic Ring Model

Table 1

H₂ and CH₄ production by rat fecal homogenates.

Gas production (ppm)^a
	H2		CH4
	1 hour	24 hours	1 hour	24 hours
Without added lactose	486 ± 220	380 ± 415	17±15	56±37
With added lactose	2,001 ± 706	14,235 ± 17,004	48±12	144±42

aOne gram of freshly collected feces in the colon was incubated as described in Methods. Lactose (1.25 g% final concentration) was added where indicated. H₂ and CH₄ were determined as described previously [1]. The concentration of the gases is expressed as part per million. The results are the average of three experiments, mean ± SD, with six rats in each experiment.