Environmental bio-oxidation of toxic furan by the co-recycling of waste fermented broth and rest cells

Abstract

Furoic acid (FA) is used widely as raw material for bio-based resin, food, pharmaceutical and perfume products. The biocatalysis of Gluconobacter oxydans is on the spotlight of furfural oxidation to FA because of high selectivity, safety and environmental friendliness. However, like most bacterial fermentations, we have to treat a lot of waste fermented broth, especially containing toxic furans. An integrated bioprocess was developed to achieve the co-recycling of cells and waste broth during FA bioproduction. We found sorbitol performed a critical role during the co-recycling bioprocess and the cost of yeast extract was substituted entirely by cheaper corn extract. Here, FA bioproduction efficiency kept six rounds with the productivity of 10.3 g/L/h and 98% yield. The integrated bioprocess provides a novel idea for biotechnology developments not only on bioconversion of toxic furans but also on industrial fermentation, especially for the troublesome problems around the recycling of waste fermented broth.