In recent years, the detrimental effects of climate change due to the increase in greenhouse gas (GHG) emissions are becoming more evident. The United States Environmental Protection Agency proposed a new Clean Air Act rule that would lead to significant, cost-effective reductions in methane emissions in support to the Global Methane Pledge for climate change mitigation. Methane is the main component of natural gas. The historic low and volatile prices of natural gas in the past decade have led to an increase in flaring which embodies wasted product, lost energy, and revenues, along with major GHG emission. Methanotrophs are gaining interests due to their capability to consume methane as their sole carbon and energy source to produce a wide variety of bio-products like lipids. These microbes are naturally present in a variety of environment such as wetlands, paddies, sediments, landfills, and waste treatment facilities. The lipids derived from methanotrophs are vital precursors for the production of green fuels and as oleochemical feedstocks. Thus, this research aimed to establish the growth conditions of methanotrophic consortium present in wastewater sludge that maximize methane consumption and lipid production. Growth parameters were varied to study the effects of media [nitrate mineral salts (NMS) and synthetic wastewater (SW)], pH (4.0 and 6.8) and methane to air volume ratio (1:1 and 1:4) on the bacterial conversion of methane to lipids. After 18 days of incubation, the consortium that was cultivated using SW medium, at pH=6.8, and methane to air volume ratio of 1:1 showed the highest methane consumption of 6.62 (vol.)% with a corresponding lipid yield of 7.27 (wt.)%. These results provide the basis of conditions for further optimization. Additionally, the findings highlight the potential of natural microbial consortium to convert methane into lipids using wastewater as medium that could address concerns on GHG emissions as well as for value-added resources recovery.

Assessing the influence of methanotrophic growth conditions on methane biocatalysis for lipid production: An initiative towards climate change mitigation

Fall 2022 abstracts, posters, and presentations will launch in mid-September.

ACS Fall 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.