SUMMARY: Enrichments were established to examine the potential of Blelham Tarn profundal sediment to metabolize benzoate to CH and CO. Long‘adaptation’ times were required before benzoate-dependent CH production occurred, though both increased inoculum size and prior methanogenic adaption to aliphatic fatty acids reduced the adaptation time. Benzoate was metabolized according to the stoichiometry: 4CHCOOH + 18HO 15CH + 13CO. The optimum temperature for CH production from benzoate in the enrichments was 37 °C irrespective of the enrichment temperature. Methanogenic benzoate degradation was associated with a particulate‘floc’ in the enrichments and was tentatively identified as an important constituent of this floc by scanning electron microscopy. Anaerobic benzoate fermentation was observed after 4 h in undiluted sediment by the use of [C]benzoate, and the temperature optimum for C-labelled gas formation was 28 °C. The CH: CO ratio indicated that methanogenic fermentation of benzoate was occurring CO became the main gaseous product from [C]benzoate when sulphate was added to sediment, and 20 mM-molybdate reversed this effect. Methanogenesis was slightly inhibited by addition of 20 mM-molybdate. Methanogenic benzoate fermentation in sediments was found to be inhibited by H.


Article metrics loading...

Loading full text...

Full text loading...

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error