A start-up company in Australia has raised about $2 million to fund research into cutting methane emissions by ruminant livestock using bromoform produced in yeast culture.
No 8 Bio will further develop its intellectual property and scale up its fermentation processes.
According to co-founder Tom Williams, bromoform could be produced considerably more cheaply than the current alternatives, which are not yet economic for large cattle herds.
Yeast culturing in precision fermentation tanks isn’t cheap in itself, but the whole biomass is harvested and fed to animals without costly downstream processing, he told the AgFunder Network website.
Bromoform disrupts the pathways of methanogens in the gut of ruminants, and several companies are now developing and promoting products using it, such as DSM with Bovaer, and CH4 and Sea Forest with asparagopsis seaweed.
Seaweed growing in land tanks has upper limits on volume because of light shadowing through what is called cellular shading, when existing cells block photosynthesis for other cells.
Yeast culturing, however, can grow to the level of a thick pea soup in a couple of days, Williams said.
“We have been able to produce a whole host of inhibitors of methanogenesis in yeast, some of which are seaweed molecules.”
The active compounds do not have to be extracted from the yeast with costly downstream processing. Instead, the yeast is dried and fed to animals.
No 8 Bio has a lot of trials ahead with different formulations, animals and their feeding systems.
It also wants to introduce circularity by using micro-organisms that feed on greenhouse gases for their carbon source, rather than sugars.
One of two Australian and New Zealand developers going the asparagopsis route, CH4 Global, said bromoform is not the sole bioactive in seaweed.
“Our data, as yet unpublished, clearly shows that, with asparagopsis, bromoform is responsible for an important percentage of the overall effect, but the other halogenated actives are responsible for even more of the effect.
“This synergistic effect is part of the magic.
“You could increase the dose of bromoform if you were just dosing bromoform to increase efficacy.
“But higher levels of bromoform could cause safety concerns that would have to be evaluated and have not, as yet.
“We are working to enhance stability, palatability and usability of our asparagopsis-containing formulations for different cattle feeding regimes.
“These efforts further demonstrate that asparagopsis is agriculture’s best bet for reducing enteric methane at scale.”