Bio-ethanol production through simultaneous saccharification and co-fermentation (SSCF) of a low-moisture anhydrous ammonia (LMAA)-pretreated napiegrass (Pennisetum purpureum Schumach)

Abstract

Efficient bio-ethanol production from napiegrass (Pennisetum purpureum Schumach) was investigated. A low-moisture anhydrous ammonia (LMAA)-pretreated napiegrass was subjected to simultaneous saccharification and co-fermentation (SSCF), which was performed at 36°C using Escherichia coli KO11, Saccharomyces cerevisiae, cellulase, and xylanase. It was found that use of xylanase as well as the LMAA-pretreatment was effective for the SSCF. After the SSCF for 96 h, the ethanol yield reached 74% of the theoretical yield based on the glucan (397 mg g-1) and xylan (214 mg g-1) occurring in dry powdered LMAA-pretreated napiergrass.

Evaluation of different pretreatments of Napier grass for enzymatic saccharification and ethanol production

“…The alkaline pretreatment with NaOH solution led to the highest glucose yield after enzymatic hydrolysis basis on per unit mass of dried raw material (0.245 g/g raw material). The ethanol yield of SSF on alkaline‐pretreated Napier grass obtained in this work (75.4%) was also higher than that from Napier grass pretreated by low‐moisture anhydrous ammonia (LMAA) and 1% NaOH . The dilute acid pretreatment yielded biomass that was relatively difficult to be hydrolyzed in the SSF process, in comparison with those treated by alkaline and two‐stage methods.…”

“…However, it is shows a low utilization of enzymatic hydrolysis when the lignocellulose biomass is used directly, because the cellulose fiber is covered with the lignin. Thus, a pretreatment step is needed to render it more accessible for hydrolytic enzyme . Numerous physical, physicochemical, chemical, and biological methods have been tested for the pretreatment of Napier grass.…”

Investigation on lignocellulosic saccharification and characterization of haloalkaline solvent tolerant endo-1,4 β-d-xylanase from Halomonas meridiana APCMST-KS4

“…Similar to the present study, the xylanse and cellulose combination exerted the crucial role in saccharification of agriculture waste (470%) at different xylanase fractions and various time intervals (Yasuda et al, 2014). Also various researchers reported the combined action of xylanase and cellulose for the enhanced saccharification using lignocellulosic substrate (Tabka et al, 2006, Kapoor et al, 2008, Kumar et al, 2012.…”

Advances in consolidated bioprocessing systems for bioethanol and butanol production from biomass: a comprehensive review

“…Co-cultures or microbial consortia may also be utilized in the CBP systems as the third methodology. Brandon et al 2011Kang et al, 2010Kim et al, 2008Geddes et al, 2011Nieves et al, 2011Mullinnix, 2014Yang et al, 2014Jin et al, 2014 Jin et al 2012aOhgren et al 2006Wang et al, 2014aYasuda et al, 2014Zhu et al, 2014Fonseca et al, 2011Teixeira et al, 1999Jin et al, 2010Tang et al, 2011Zhang (J) et al, 2009Kim and Lee, 2005Zhang et al, 2012bYu et al, 2014Moreno et al, 2013Erdei et al, 2013aBallesteros et al, 2013Geddes et al, 2013Turhan et al, 2014Lan et al, 2013Hargreaves et al, 2013Alvira et al, 2011Olofsson et al, 2010a . In co-culture systems, saccharolytic and ethanologenic microorganisms are co-cultured to enhance efficient saccharification and fermentation in one pot.…”

“…Clearlly, in lignocellulosic ethanol production, in addition to hexose fermentation, pentose fermentation is also an unavoidable part of the process due to the high xylan content of the lignocellulosic materials. However, ethanol concentration in pentose fermentation process is usually too low (<10 g/l), and therefore, is not economic to be distilled (Yasuda et al, 2014). Thus, co-fermentation of hexose and pentose has been performed using a variety of wild type and recombinant microorganisms for ethanol production from different lignocellulosic materials.…”