Research Article

The Ability of Hop Extracts to Reduce the Methane Production of Methanobrevibacter ruminantium

Table 1

The percentage reduction of methane by aqueous and commercial hop extracts, metronidazole (4.5 mg/ml), and water compared to an untreated control at 10-day time points over 30 days. Results are an average of 3 separate repeats.

ControlsPercentage methane produced at
Day 10Day 20Day 30
 Metronidazole 4.5 mg/ml0%0%0%
 Sterile distilled water100%100%100%
Hop extractsPercentage methane produced
 Citra3%32%42%
 Fuggles2%26%49%
 Willamette2%20%50%
 Magnum6%39%62%
 Northdown5%23%68%
Commercial hop extractsPercentage methane produced
 Tetra-hydro-iso-alpha acid29%1%1%
 Beta acid9%1%1%