Ujor is an assistant professor of food science at UW–Madison. His research interests include renewable fuels and chemicals, metabolic engineering/synthetic biology, bio-based waste-to-energy technologies, and bioprocess design.
Postdoc (pictured above): Ademola Duduyemi is the postdoc on the project with research interests centered on advancing a circular economy by utilizing agricultural and industrial wastes as low-cost substrates for the sustainable and cleaner production of biofuels and platform chemicals.
Bioconversion of whey permeate (WP) to value-added compounds and materials is a key prerequisite to eliminating the burden of this waste stream on the dairy industry, and in turn, safeguarding water and soil quality, whilst enhancing the economics of dairy operations. The central thrust of the proposed study is to convert WP at 12-liter bioreactor scale to 2,3-butanediol (2,3BD)–a versatile chemical with numerous industrial applications. We have isolated, sequenced and characterized a strain of Enterobacter hormaechei that produces 42 g/L 2,3BD on lactose as the sole carbon source. In the proposed study, we will demonstrate the use of lactose-rich WP to produce similar titer of 2,3BD in batch fermentation. Additionally, we will use fed-batch fermentation to increase 2,3BD titer to 55 – 60 g/L. In an effort to pave the way for potential commercial scale application of this strain of E. hormaechei to produce 2,3BD in WP, we will de-risk such an effort by inactivating major antibiotic resistance genes in the genome of this organism. The proposed study will provide multifaceted training in fermentation science, analytical chemistry and synthetic biology for a postdoctoral fellow. The results are expected to forge a roadmap for future efforts to convert WP to 2,3BD at pilot scale. Additionally, it is anticipated that the findings will engender similar efforts to de-risk other microorganisms that produce high concentrations of different important compounds, albeit with inherent risks associated with the spread of antibiotic resistance or virulence genes.