Using microbes to capture carbon is more cost-effective than harnessing technologies such as direct air capture, says Onyeaka.
“Microbial processes generally have low operational costs compared to technological interventions for carbon capture, which can often be capital-intensive,” she says. They are also “inherently scalable” as microbes “can be deployed in diverse environments, from open ponds to bioreactors”, she adds.
But technological constraints make scaling up these kinds of systems difficult, says Schipper. “Best-practices to select top strains, to cultivate them at large scale, including maximising the amount of CO2 that is absorbed, and then to harvest the biomass, are challenging and vary drastically between strains and locations.” Some companies have already started implementing systems to capture CO2 using microbes. In the US, LanzaTech uses bacteria to convert CO2 into aviation fuels and chemicals used in products ranging from laundry detergents to perfumes. UK company CyanoCapture is using cyanobacteria to produce biological oils and biomass.
Microbes could also have a multitude of other environmental benefits besides their carbon capture potential. According to a recent Canadian study, for example, they could help revive dying honeybee populations.
Pollinator populations are steadily declining worldwide, and the US saw its highest ever yearly loss rate for honey bee colonies between 2020 and 2021. (Read more: Can we save the bees that feed the world?)
Microbiologist Brendan Daisley from the University of Guelph in Canada set out to combat this “insect apocalypse” by developing probiotics that boost the health of bees.
Just like humans, bees have a microbiome and a healthy balance of microbes in their gut is essential for their overall health. Studies show that pesticides and antibiotics are harming the microbiota of bees, impacting their health.
This is also affecting crop production and food supply, warns Daisley. “It is a cascading effect,” he says. According to a 2020 study, a lack of bees is already limiting the supply of certain crops, including apples, blueberries and cherries, in 13 US states.
By targeting hives with probiotics, the scientists aimed “to re-establish microbial balance in honeybees,” says Daisley, who is a scientific fellow at Seed Health. Alongside a team of researchers from Western University and Lawson Health Research Institute in Canada, he delivered three probiotic strains to more than 30 large commercial hives in California, using a spray and a pollen patty infusion.
Both methods were shown to be highly effective at warding off bacterial and fungal pathogens.
The probiotics also increased the growth of the targeted hives, says Daisley.
Partnering with Seed Health, the scientists are now developing patents for the strains.