Influence of fiber degradation and concentration of fermentable sugars on simultaneous saccharification and fermentation of high-solids spruce slurry to ethanol

Hoyer, Kerstin; Galbe, Mats; Zacchi, Guido

doi:10.1186/1754-6834-6-145

Cited by 22 publications

(19 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Glucose yield was generally higher than in the study of Zhang et al [35]. This could be due to the lower WIS concentration adopted in our experiment, given the fact that high WIS concentration affects enzymatic activity, resulting in decreased yield [28,36]. The study carried out by Goshadrou et al [37] corroborates this hypothesis: a glucose yield (65%) very close to ours was obtained in sweet sorghum bagasse, running enzymatic hydrolysis at a similar WIS concentration.…”

Section: Enzymatic Hydrolysissupporting

confidence: 76%

Crop Factors Influencing Ethanol Production from Sorghum Juice and Bagasse

et al. 2017

View full text Add to dashboard Cite

This study investigated the effects of two soil moisture levels (SM) (30% and 70% soil available water) and three harvests (90 days, 118 days, and 151 days after seeding) on sweet (S506) and fiber (B133) sorghum genotypes under rain-sheltered conditions. Juice and bagasse-derived ethanol and their sum (EtOH BJ , EtOH B , and EtOH J+B , respectively) were assessed. Water use efficiency (WUE) was determined for sorghum dry weight (DW) and EtOH J+B . S506 had similar DW, but higher sugar content than B133, resulting in higher EtOH J (+32%) and EtOH J+B (+9%). High SM-enhanced DW, juice and sugars content, determining a strong EtOH J+B increase (+99% vs. low SM). Late harvest enhanced DW and EtOH J+B (+107% vs. early harvest), despite decreasing extractives and increasing structural fiber components. Water use efficiency of EtOH J+B improved with high vs. low SM, although differences faded in late harvest. Upscale of EtOH J+B and WUE data indicated a range of 21,000-82,000 ha of sorghum cultivation and 60-117 Mm 3 of irrigation water, as amounts of resources needed to supply an 85,000 m 3 ·yr −1 bio-ethanol plant. This large variation in land and water needs depended on specific combinations between crop factors SM and harvests.

show abstract

Section: Enzymatic Hydrolysissupporting

confidence: 76%

Crop Factors Influencing Ethanol Production from Sorghum Juice and Bagasse

et al. 2017

View full text Add to dashboard Cite

show abstract

“…On the other hand, Varga et al [51] achieved 52 g/L of ethanol (6% v/v) corresponding to 78% ethanol yield by SSF from wet oxidized corn stover dry matter (17% of solid and enzyme loading of 43.5 FPU/g cellulose). In other study where SSF was carried out with whole steam-pretreated spruce slurry at 13.7% of solid, very low ethanol yield was obtained, however the yield increased from 3.9% to 62.1% when a prehydrolysis (48°C for 24 h) was realized [52].…”

Section: Simultaneous Saccharification and Fermentation Of Optimal Comentioning

confidence: 92%

Integrated approach for effective bioethanol production using whole slurry from autohydrolyzed Eucalyptus globulus wood at high-solid loadings

Romaní

Ruiz

Pereira

et al. 2014

Fuel

View full text Add to dashboard Cite

h i g h l i g h t sIntegrated process optimization was evaluated for 2G bioethanol production. Enzymatic saccharification of whole-slurry from pretreatment was optimized. Two strategies with/without presaccharification to ethanol production were compared. Optimized conditions lead ethanol titer >6% using industrial yeast strain by SSF. Effective bioethanol production from whole slurry E. globulus was achieved. a b s t r a c tOne of the most important targets and challenges in the second generation bioethanol is the development of a cost-effective process on large-scale. In this context, the high solid loading on saccharification and fermentation and the use of whole-slurry from pretreatment could be promising alternatives to obtain high ethanol concentrations and to decrease operational costs and wastewater. In this work, Eucalyptus globulus wood was submitted to non-isothermal autohydrolysis treatment (T max = 210°C) and the whole-slurry obtained was assayed for the optimization of enzymatic saccharification at different solid and enzymes (CTec2 and HTec2) loadings using a Box-Behnken experimental design. Under the optimized conditions (liquid solid ratio 6.4 g/g, cellulase to substrate ratio 22.5 FPU/g and hemicellulase to substrate ratio 500 UI/g), two strategies were evaluated for ethanol production (Simultaneous Saccharification and Fermentation, SSF and Presaccharification and Simultaneous Saccharification and Fermentation, PSSF), using an industrial and robust Saccharomyces cerevisiae strain. High concentrations of ethanol (50.2 and 48.8 g/L) and productivities (0.63 and 0.55 g/L h) were obtained by SSF and PSSF, respectively. The SSF process proved to be an advantageous strategy to obtain concentrations >6% (v/v) of ethanol with elevated conversion (95%) even employing high solid loading and non-detoxified hydrolysate. Following an integrated optimization process, cost-effective bioethanol production conditions from whole-slurry E. globulus wood were determined and validated experimentally, representing a step-forward towards its industrial implementation.

show abstract

“…Also, when a 24 h pre-hydrolysis step was used prior to simultaneous saccharification and fermentation (pSSF), the corresponding ethanol productivity and fermentation efficiency were lower at 0.55 g L −1 h −1 and 92.1 %, respectively. Since pSSF usually gives better ethanol productivities than SSF [23,33], this unexpected result was probably due to the presence of inhibitors in the fermentation media. By contrast, Neves et al [24] , respectively.…”

Section: Fermentationmentioning

confidence: 99%

“…However, SSF does not allow yeast recycling and hydrolysis is usually carried out below its optimal temperature. In both configurations mentioned above, ethanol yields can be increased if the fermenting organism is able to convert pentoses and hexoses simultaneously [23,24].…”

Section: Introductionmentioning

confidence: 99%

Production of cellulosic ethanol from steam-exploded Eucalyptus urograndis and sugarcane bagasse at high total solids and low enzyme loadings

Chiarello

Ramos

Neves

et al. 2016

Sustain Chem Process

View full text Add to dashboard Cite

Cellulosic ethanol is one of the most important biotechnological products to mitigate the consumption of fossil fuels and to increase the use of renewable resources for fuels and chemicals. By performing this process at high total solids (TS) and low enzyme loadings (EL), one can achieve significant improvements in the overall cellulosic ethanol production process. In this work, steam-exploded materials were obtained from Eucalyptus urograndis chips and sugarcane bagasse to be subsequently used for enzymatic hydrolysis at high TS (20 wt%) and relatively low EL (13.3 FPU g −1 TS of Cellic CTec3 from Novozymes). Also, the fermentability of their corresponding hydrolysates was tested using an industrial strain of Saccharomyces cerevisiae (Thermosacc Dry from Lallemand). Enzymatic hydrolysis of steam-treated E. urograndis reached 125 g L −1 of glucose in 72 h, while steam-treated bagasse gave yields 25 % lower. Both substrate hydrolysates were easily converted to ethanol, giving yields above 25 g L −1 and productivities of 2.3 g L −1 h −1 for eucalypt and 2.2 g L −1 h −1 for bagasse after only 12 h of fermentation. Under the conditions used in this study, sugarcane bagasse glucans showed the potential to boost the ethanol production from sugarcane culms by 31 %, from the 80 L t −1 of first generation to a total production of 105 L t −1. On the other hand, E. urograndis plantations are able to achieve cellulosic ethanol productivities of 2832.2 L ha −1 year −1 , which was 57.8 % higher than the projected value of 1794.5 L ha −1 year −1 that was obtained for sugarcane bagasse.

show abstract

Influence of fiber degradation and concentration of fermentable sugars on simultaneous saccharification and fermentation of high-solids spruce slurry to ethanol

Cited by 22 publications

References 28 publications

Crop Factors Influencing Ethanol Production from Sorghum Juice and Bagasse

Crop Factors Influencing Ethanol Production from Sorghum Juice and Bagasse

Integrated approach for effective bioethanol production using whole slurry from autohydrolyzed Eucalyptus globulus wood at high-solid loadings

Production of cellulosic ethanol from steam-exploded Eucalyptus urograndis and sugarcane bagasse at high total solids and low enzyme loadings

Contact Info

Product

Resources

About