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Methanogenesis from acetate: enrichment studies.

L Baresi·R A Mah·D M Ward·I R Kaplan
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Abstract

An acetate enrichment culture was initiated by inoculating anaerobic sludge from a mesophilic methane digestor into a mineral salts medium with calcium acetate as the sole carbon and energy source. This enrichment was maintained indefinitely by weekly transfer into medium of the same composition. A study of this enrichment disclosed an unexpected age-dependent inhibition of methanogenesis by H2 and formate which apparently differed from the inhibition by chloroform and benzyl viologen. This age-dependent inhibition indicated that microbial interactions of the mixed enrichment population may play a regulatory role in methane formation. Futhermore, stimulation of methanogenesis in the acetate enrichment by addition of yeast extract showed a nutrient limitation which indicated that syntrophic interactions leading to formation of growth factors may also occur. A model is presented to illustrate the possible interrelationships between methanogenic and nonmethanogenic bacteria in their growth and formation of methane and carbon dioxide from acetate.

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AcetatesAnaerobiosisBacteriaBenzyl ViologenChloroformCulture MediaEuryarchaeotaFormatesGlucoseHydrogenMethaneSewageWater MicrobiologyJournal Article

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L Baresi, R A Mah, D M Ward, I R Kaplan. 1978. Methanogenesis from acetate: enrichment studies.. https://doi.org/10.1128/aem.36.1.186-197.1978

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