Journal of Chemical Technology and Biotechnology, Vol.92, No.10, 2635-2641, 2017
Dihydroxyacetone production by Gluconobacter frateurii in a minimum medium using fed-batch fermentation
BACKGROUNDGlycerol, a major by-product of biodiesel production, is used as a sole carbon source supplemented with only inorganic salts for dihydroxyacetone (DHA) production by Gluconobacter frateuriiBCC36199 using fed-batch fermentation (FBF). Such a FBF process that relies on only glycerol and inorganic salts as carbon and nitrogen sources have never been reported. The effects of dissolved oxygen (DO) and harvest time on DHA production were studied in bioreactor batch fermentation (BBF) and applied to practical FBF. RESULTSThe highest DHA yield of 96.04% was obtained for culture conditions of 70% DO. The fastest DHA production rate and the highest biomass were obtained under fermentation conditions with 90% DO. FBF with 90% DO gave DHA that was significantly higher than BBF by 82.63%, and very high DHA yield of 96.77% was obtained. CONCLUSIONDO positively affects the DHA production in bioreactor by G. frateuriiBCC36199. High conversion yields of glycerol to DHA by G. frateuriiBCC36199 in BBF and FBF are obtained. The developed FBF process is economical because the minimum medium contains only glycerol and inexpensive inorganic salts. The process is designed to be a simple FBF for a more plausible industrial application. (c) 2017 Society of Chemical Industry
Keywords:dihydroxyacetone;glycerol;Gluconobacter frateurii;fed-batch fermentation;biotechnology;bioreactor