BioChem - DOS

Synergistic positive effect of organic acids on the inhibitory effect of phenolic compounds on Acetone-Butanol-Ethanol (ABE) production

Food and bioproducts processing : transactions of the Institution of Chemical Engineers, Part C

Bellido, Carolina; Lucas, Susana; Gonzá lez-Benito, Gerardo; Garcí a-Cubero, M. Teresa; Coca, Mó nica

<P><B>Abstract</B></P> <P>The synergistic effect of potential inhibitory compounds (organic acids and phenolic compounds) on ABE fermentation was studied with model media containing sucrose and real media prepared from beet and cane sugar refining molasses.</P> <P>The presence of phenolic compounds inhibited ABE fermentation at concentrations as low as 0.5g/L for gallic acid and 0.1g/L for catechin. The co-presence of organic acids (2.2g/L acetic, 1.8g/L lactic and 0.6g/L formic) showed a synergistic positive effect that can counteract the inhibitory character of phenolics. This effect was significantly higher at low phenolic concentrations. This means that the inhibitory effect of phenolic compounds on ABE production with <I>Clostridium beijerinckii</I> could be overcome by the presence of organic acids at low concentration in fermentation media.</P> <P>The results were confirmed by using a substrate of molasses. Better fermentation was achieved with beet molasses due to the lower concentration of phenolics, especially catechin. The fermentation using beet and cane sugar refining molasses as substrate (60g/L) provided an ABE yield of 0.40g ABE/g sugars and 0.31g ABE/g sugars, respectively and ABE concentrations of 12.3g/L (205g ABE/kg beet molasses) and 7g ABE/L (120g ABE/kg cane molasses).</P> <P><B>Highlights</B></P> <P> <UL> <LI> ABE fermentation by <I>Clostridium beijerinckii</I> of molasses. </LI> <LI> Phenolic compounds inhibited ABE fermentation at low concentrations. </LI> <LI> Inhibition by phenolics could be overcome through organic acids addition. </LI> <LI> Beet molasses more favourable for ABE fermentation than cane molasses. </LI> <LI> Complete inhibition for molasses concentrations higher than 80g/L. </LI> </UL> </P>

2018

Elsevier

0960-3085

108

pp.117-125

10.1016/j.fbp.2018.02.004

http://click.ndsl.kr/servlet/OpenAPIDetailView?keyValue=05787966&target=NART&cn=NART81670476

Molasses; ABE fermentation; Clostridium beijerinckii; Fermentation inhibitors; Phenolic compounds; Organic acids