BioChem - DOS

Continuous gas fermentation by Acetobacterium woodii in a submerged membrane reactor with full cell retention

Journal of biotechnology

Kantzow, C.; Mayer, A.; Weuster-Botz, D.

Acetogenic bacteria like Acetobacterium woodii represent an ancient group of anaerobic microorganisms which use hydrogen and carbon dioxide to produce acetate. Cell concentrations and space-time yields are usually low in gas fermentations. A standard stirred@?tank bioreactor with continuous gas supply was equipped with a customized submerged microfiltration unit. A. woodii showed similar growth behavior with an initial maximal growth rate of 1.2d<SUP>-1</SUP> in continuous gas fermentations with full cell retention and varying dilution rates. A steady increase of cell mass concentrations was observed with the highest biomass formation at the highest dilution rate. By contrast the final acetate concentrations were lowest at the highest dilution rate. The highest final acetate space-time yield of 148gl<SUP>-1</SUP>d<SUP>-1</SUP> was measured at the highest dilution rate (increase by factor 8 compared to a standard batch process or by factor 37 compared to published data). The highest reported cell concentration of A. woodii in gas fermentations of nearly 14gl<SUP>-1</SUP> cell dry weight was achieved in the submerged membrane bioreactor with increased yeast extract concentrations in the feed medium. Product inhibition was observed when acetate concentrations exceeded 8-12gl<SUP>-1</SUP> causing a steady decrease in cell mass specific acetate production rates.

2015

Elsevier Science Publishers

0168-1656

1873-4863

212

pp.11-18

10.1016/j.jbiotec.2015.07.020

http://click.ndsl.kr/servlet/OpenAPIDetailView?keyValue=05787966&target=NART&cn=NART73180824

Submerged microfiltration membranes; Membrane bioreactor; Acetobacterium woodii; Acetate; Gas fermentation; Autotrophic