BioChem - DOS

Simultaneous saccharification and aerobic fermentation of high titer cellulosic citric acid by filamentous fungus Aspergillus niger

Bioresource technology : biomass, bioenergy, biowastes, conversion technologies, biotransformations, production technologies

Hou, Weiliang; Bao, Jie

<P><B>Abstract</B></P> <P>Simultaneous saccharification and fermentation (SSF) is the most efficient operation in biorefining conversion, but aerobic SSF under high solids loading significantly faces the serious oxygen transfer limitation. This study took the first insight into an aerobic SSF by high oxygen demanding filamentous fungi in highly viscous lignocellulose hydrolysate. The results show that oxygen requirement in the aerobic SSF by <I>Aspergillus niger</I> was well satisfied for production of cellulosic citric acid. The record high citric acid titer of 136.3 g/L and the overall conversion yield of 74.9% of cellulose were obtained by the aerobic SSF. The advantage of SSF to the separate hydrolysis and fermentation (SHF) on citric acid fermentation was compared based on the rigorous Aspen Plus modeling. The techno-economic analysis indicates that the minimum citric acid selling price (MCSP) of $0.603 per kilogram by SSF was highly competitive with the commercial citric acid from starch feedstock.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Oxygen transfer was satisfied for aerobic SSF by <I>A. niger</I> fungus. </LI> <LI> A record high cellulosic citric acid titer of 136.3 g/L was obtained. </LI> <LI> Advantages of aerobic SSF to SHF were demonstrated. </LI> <LI> Cellulosic citric acid by SSF was highly competitive to the starch citric acid. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

2018

Elsevier

0960-8524

253

pp.72-78

10.1016/j.biortech.2018.01.011

http://click.ndsl.kr/servlet/OpenAPIDetailView?keyValue=05787966&target=NART&cn=NART80572884

Simultaneous saccharification and fermentation (SSF); Citric acid; Lignocellulose; Aerobic fermentation; Aspergillus niger