Paul de Figueiredo and Daniel Alge of Texas A&M University in the U.S. will develop a portable, disposable bioreactor for the low-cost production of gut microbial biotherapeutics at an estimated $0.09 per dose in low-resource settings. Dysfunction of the human gut microbiome is a common consequence of malnutrition in poor countries. It may be effectively treated with live biotherapeutics, yet current production methods are complicated and expensive. Glucose oxidase consumes oxygen as a co-substrate in glucose oxidation and has been shown to create hypoxic microenvironments in vitro, similar to that in the human gastrointestinal tract. They will engineer an inexpensive bioreactor by immobilizing glucose oxidase in a hydrogel placed in dialysis tubing and incubated in liquid media; the glucose oxidation reaction will deplete the bioreactor of oxygen and create an oxygen gradient to mimic the intestinal lumen. This will enable growth of a consortium of anaerobic bacteria, after which the microparticles will be removed by filtration. They will optimize the system using an artificial consortium of at least ten strains of common gut bacteria.