Sustainable production of C50 carotenoid bacterioruberin from methane using soil-enriched microbial consortia

Bacterioruberin is widely used in medicine, food, and cosmetics owing to its prominent characteristics of antioxidants and bioactivities. Bioconversion of methane into bacterioruberin is a promising way to address biomanufacturing substrate costs and greenhouse gas emissions but has not been achieved yet. Herein, this study aimed to upcycle methane to bacterioruberin by microbial consortia. The microbial consortia consist of Methylomonas and Methylophilus capable of synthesizing carotenoids from methane was firstly enriched from paddy soil. Through this microbial community, methane was successfully converted into C50 bacterioruberin for the first time. The bioconversion process was then optimized by the response surface methodology. Finally, the methane-derived bacterioruberin reached a record yield of 280.88 ± 2.94 μg/g dry cell weight. This study presents a cost-effective and eco-friendly approach for producing long-chain carotenoids from methane, offering a significant advancement in the direct conversion of greenhouse gases into value-added products.