Effect of Residual Extractable Lignin on Acetone-Butanol-Ethanol Production in SHF and SSF Processes

Ssf Process ◽

Acetone Butanol Ethanol ◽

Abstract Background Lignin played an important role in biochemical conversion of biomass to biofuels. A significant amount of lignin is precipitated on the surface of pretreated substrates after organosolv pretreatment. The effect of this residual lignin on enzymatic hydrolysis has been well understood, however, their effect on subsequent ABE fermentation is still unknown. Results To determine the effect of residual extractable lignin on Acetone-Butanol-Ethanol (ABE) fermentation in separate hydrolysis and fermentation (SHF) and simultaneous saccharification and fermentation (SSF) processes, we compared ABE production from ethanol washed and unwashed substrates. The ethanol organosolv pretreated loblolly pine (OPLP) was used as the substrate. It was observed that butanol production from OPLP-UW (unwashed) and OPLP-W(washed) reached 8.16 and 1.69 g/L, respectively in SHF. The results showed that ABE production in SHF from OPLP-UW prevents an “acid crash” as comparing the OPLP-W. In SSF process, the “acid crash” occurred for both OPLP-W and OPLP-UW. The inhibitory extractable lignin intensified the “acid crash” for OPLP-UW and resulted in less ABE production than OPLP-W. The addition of detoxified prehydrolysates in SSF processes shortened the fermentation time and could potentially prevent the “acid crash”. Conclusions The results suggested that the residual extractable lignin in high sugar concentration could help ABE production by lowering the metabolic rate and preventing “acid crash” in SHF processes. However, it became unfavorable in SSF due to its inhibition of both enzymatic hydrolysis and ABE fermentation with low initial sugar concentration. It is essential to remove extractable lignin of substrates for ABE production in SSF processes. Also, a higher initial sugar concentration is needed to prevent the “acid crash” in SSF processes.

Effect of Residual Extractable Lignin on Acetone-Butanol-Ethanol Production in SHF and SSF Processes

10.21203/rs.2.23353/v1 ◽

2020 ◽

Author(s):

Jing Li ◽

Yu Zhang ◽

Suan Shi ◽

Maobing Tu

Keyword(s):

Enzymatic Hydrolysis ◽

Loblolly Pine ◽

Abe Fermentation ◽

Sugar Concentration ◽

Fermentation Time ◽

High Sugar Concentration ◽

Ssf Process ◽

Acetone Butanol Ethanol ◽

Abstract Background Lignin played an important role in biochemical conversion of biomass to biofuels. A significant amount of lignin is precipitated on the surface of pretreated substrates after organosolv pretreatment. The effect of this residual lignin on enzymatic hydrolysis has been well understood, however, their effect on subsequent ABE fermentation is still unknown. Results To determine the effect of residual extractable lignin on Acetone-Butanol-Ethanol (ABE) fermentation in separate hydrolysis and fermentation (SHF) and simultaneous saccharification and fermentation (SSF) processes, we compared ABE production from ethanol washed and unwashed substrates. The ethanol organosolv pretreated loblolly pine (OPLP) was used as the substrates. It was observed that butanol production from OPLP-UW (unwashed) and OPLP-W(washed) reached 8.16 and 1.69 g/L, respectively in SHF. The results showed that ABE production in SHF from OPLP-UW prevents an “acid crash” as comparing the OPLP-W. In SSF process, the “acid crash” occurred for both OPLP-W and OPLP-UW. The inhibitory extractable lignin intensified the “acid crash” for OPLP-UW and resulted in less ABE production than OPLP-W. The addition of detoxified prehydrolysates in SSF processes shortened the fermentation time and could potentially prevent the “acid crash”. Conclusions The results suggested that residual extractable lignin in high sugar concentration could help ABE production by slowing the metabolic rate and preventing “acid crash”. However, it became unfavorable in SSF due to its inhibition of both enzymatic hydrolysis and ABE fermentation with low initial sugar concentration. It is essential to remove extractable lignin of substrates for ABE production in SSF processes. And a higher initial sugar concentration is needed to prevent the “acid crash” in SSF processes.

Ethanol Production from Hydrothermal Pretreated Empty Fruit Bunches

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.917.80 ◽

2014 ◽

Vol 917 ◽

pp. 80-86

Author(s):

Mohd Saman Siti Aisyah ◽

Pacharakamol Petchpradab ◽

Yoshimitsu Uemura ◽

Suzana Yusup ◽

Machi Kanna ◽

...

Keyword(s):

Ethanol Production ◽

Lignocellulosic Biomass ◽

Simultaneous Saccharification And Fermentation ◽

Process Time ◽

Empty Fruit Bunches ◽

Common Process ◽

The Common ◽

Ssf Process ◽

Separate hydrolysis and fermentation (SHF) is the common process in producing ethanol from lignocellulosic biomass. Nowadays, simultaneous saccharification and fermentation (SSF) process has been seen as potential process for producing ethanol with shortens process time with higher yield of ethanol. Hence, in the current work, the utilization of empty fruit bunches (EFB) in SSF process was studied. In order to improve saccharification reactivity of EFB, hydrothermal pretreatment at 180 and 220 °C was used to pretreat EFB. The findings showed that SSF has the potential in producing ethanol from EFB.

Enzymatic hydrolysis and fermentation strategies for the biorefining of pine sawdust

BioResources ◽

10.15376/biores.16.4.7474-7491 ◽

2021 ◽

Vol 16 (4) ◽

pp. 7474-7491

Author(s):

Carolina Mónica Mendieta ◽

Fernando Esteban Felissia ◽

Ana María Arismendy ◽

Julia Kruyeniski ◽

María Cristina Area

Keyword(s):

Enzymatic Hydrolysis ◽

Simultaneous Saccharification And Fermentation ◽

Design Tool ◽

Cellulolytic Enzymes ◽

Chemical Compositions ◽

Pine Sawdust ◽

Second Generation Bioethanol ◽

Experimental Values ◽

This work aims to evaluate second-generation bioethanol production from the soda-ethanol pulp of pine sawdust via two strategies: separate hydrolysis and fermentation and simultaneous saccharification and fermentation. A kinetics study of the enzymatic hydrolysis of separate hydrolysis and fermentation was included as a design tool. Three soda-ethanol pulps (with different chemical compositions), Cellic® Ctec2 cellulolytic enzymes, and Saccharomyces cerevisiae IMR 1181 (SC 1181) yeast were employed. The obtained kinetic parameters were as follows: an apparent constant (k) of 11.4 h-1, which represents the link frequency between cellulose and cellulase; a Michaelis-Menten apparent constant (KM) of 23.5 gL-1, that indicates the cellulose/cellulase affinity; and the apparent constant of inhibition between cellulose-glucose and cellulase (KI), which was 2.9 gL-1, 3.1 gL-1, and 6.6 gL-1 for pulps 1, 2, and 3, respectively. The kinetic model was applicable, since the calculated glucose values fit the experimental values. High bioethanol yields were obtained for pulp 3 in the separate hydrolysis and fermentation and simultaneous saccharification and fermentation processes (89.3% and 100% after 13 h and 72 h, respectively).

Effect of salts formed by neutralization for the enzymatic hydrolysis of cellulose and acetone–butanol–ethanol fermentation

RSC Advances ◽

10.1039/c9ra06869d ◽

2019 ◽

Vol 9 (58) ◽

pp. 33755-33760 ◽

Cited By ~ 5

Author(s):

Ming Yang ◽

Jia Wang ◽

Yufei Nan ◽

Junhua Zhang ◽

Liyun Li ◽

...

Keyword(s):

Citric Acid ◽

Enzymatic Hydrolysis ◽

Ethanol Fermentation ◽

Abe Fermentation ◽

Lignocellulosic Materials ◽

Enzymatic Hydrolysis Of Cellulose ◽

Hydrolysis Of Cellulose ◽

Acetone Butanol Ethanol ◽

Hydrolysis Of

The salts formed by neutralization after sulfuric, acetic, and citric acid pretreatments affected enzymatic hydrolysis of lignocellulosic materials and acetone–butanol–ethanol (ABE) fermentation to various degrees.

Acetone–butanol–ethanol production by separate hydrolysis and fermentation (SHF) and simultaneous saccharification and fermentation (SSF) methods using acorns and wood chips of Quercus acutissima as a carbon source

Industrial Crops and Products ◽

10.1016/j.indcrop.2014.08.049 ◽

2014 ◽

Vol 62 ◽

pp. 286-292 ◽

Cited By ~ 21

Author(s):

Chizuru Sasaki ◽

Yohei Kushiki ◽

Chikako Asada ◽

Yoshitoshi Nakamura

Keyword(s):

Carbon Source ◽

Ethanol Production ◽

Simultaneous Saccharification And Fermentation ◽

Wood Chips ◽

Quercus Acutissima ◽

Acetone Butanol Ethanol ◽

Bioethanol Production from Cellulose-Rich Corncob Residue by the Thermotolerant Saccharomyces cerevisiae TC-5

Journal of Fungi ◽

10.3390/jof7070547 ◽

2021 ◽

Vol 7 (7) ◽

pp. 547

Author(s):

Pinpanit Boonchuay ◽

Charin Techapun ◽

Noppol Leksawasdi ◽

Phisit Seesuriyachan ◽

Prasert Hanmoungjai ◽

...

Keyword(s):

Saccharomyces Cerevisiae ◽

Elevated Temperatures ◽

Ethanol Concentration ◽

Ethanol Productivity ◽

Solid Loading ◽

Bioethanol Production ◽

Fed Batch ◽

Ssf Process ◽

This study aimed to select thermotolerant yeast for bioethanol production from cellulose-rich corncob (CRC) residue. An effective yeast strain was identified as Saccharomyces cerevisiae TC-5. Bioethanol production from CRC residue via separate hydrolysis and fermentation (SHF), simultaneous saccharification and fermentation (SSF), and prehydrolysis-SSF (pre-SSF) using this strain were examined at 35–42 °C compared with the use of commercial S. cerevisiae. Temperatures up to 40 °C did not affect ethanol production by TC-5. The ethanol concentration obtained via the commercial S. cerevisiae decreased with increasing temperatures. The highest bioethanol concentrations obtained via SHF, SSF, and pre-SSF at 35–40 °C of strain TC-5 were not significantly different (20.13–21.64 g/L). The SSF process, with the highest ethanol productivity (0.291 g/L/h), was chosen to study the effect of solid loading at 40 °C. A CRC level of 12.5% (w/v) via fed-batch SSF resulted in the highest ethanol concentrations of 38.23 g/L. Thereafter, bioethanol production via fed-batch SSF with 12.5% (w/v) CRC was performed in 5-L bioreactor. The maximum ethanol concentration and ethanol productivity values were 31.96 g/L and 0.222 g/L/h, respectively. The thermotolerant S. cerevisiae TC-5 is promising yeast for bioethanol production under elevated temperatures via SSF and the use of second-generation substrates.