BioChem - DOS

Production of medium-chain carboxylic acids by anaerobic fermentation of glycerol using a bioaugmented open culture

Biomass & bioenergy

Dams, Rosemeri I.; Viana, Michael B.; Guilherme, Alexandre A.; Silva, Camila M.; dos Santos, André B.; Angenent, Largus T.; Santaella, Sandra T.; Leitã o, Renato C.

<P><B>Abstract</B></P> <P>Biological production of carboxylic acids during glycerol fermentation <I>via</I> the chain elongation process was investigated. Glycerol is a by-product of the biodiesel production process and a convenient feedstock alternative for the carboxylate platform. In batch experiments, glycerol was used as substrate, whereas sludge (granular and flocculent) and ruminal liquid served as inocula. To improve the production of carboxylates, bioaugmentation with <I>Clostridium acetobutylicum</I> ATCC 824 was performed. Maximal production of <I>n</I>-caproic and <I>n-</I>caprylic acids was achieved with the use of the granular sludge. Bioaugmentation with <I>C. acetobutylicum</I> enhanced production of <I>n</I>-caproic acid in the presence of 100 mM ethanol. However, increasing ethanol concentration to 200 mM had no further enhancing effect on <I>n</I>-caproic production with or without bioaugmentation. The enhancement of <I>n</I>-caproic acid production was probably due to the increased production of <I>n</I>-butyric acid by <I>C. acetobutylicum</I>, because <I>n</I>-butyric acid is an important intermediate in the chain elongation process when ethanol is used as an electron donor.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Bioaugmentation to improve metabolites production. </LI> <LI> Mixed culture bioaugmented with <I>Clostridium acetobutylicum</I> ATCC 824. </LI> <LI> Residual glycerol as low cost feedstock. </LI> <LI> Ethanol as electron donor to chain elongation of MCCA. </LI> <LI> Simultaneously production of <I>n</I>-caproic acid and 1,3-propanediol. </LI> </UL> </P>

2018

Elsevier

cc-by-nc-nd

0961-9534

118

pp.1-7

10.1016/j.biombioe.2018.07.023

http://click.ndsl.kr/servlet/OpenAPIDetailView?keyValue=05787966&target=NART&cn=NART89958590

http://www.alice.cnptia.embrapa.br/bitstream/doc/1102654/1/ART18089.pdf

Glycerol; Anaerobic digestion; Carboxylate platform; Chain elongation; Bioaugmentation; Clostridium acetobutylicum