Sugarcane bagasse hydrolysis with phosphoric and sulfuric acids and hydrolysate detoxification for xylitol production

Carvalho, Walter; Batista, Marcio A; Canilha, Larissa; Santos, Júlio César dos; Converti, Attílio; Silva, Sílvio S.

doi:10.1002/jctb.1131

Cited by 31 publications

(15 citation statements)

References 14 publications

(17 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…1 as an example). It was also stressed that low concentrations of this acid can favor xylose bioconversion by yeasts (Carvalho et al, 2002;Felipe et al, 1995), likely because its respiration can favor the bioenergetics of the system (Carvalho et al, 2004). This hypothesis is confirmed in this study by the results summarized in Table VI, which demonstrate the significance of this catabolic activity on the main bioenergetic parameters associated to acetate consumption by the TCA cycle.…”

Section: Influence Of Acetic Acid On the Energetic Metabolismsupporting

confidence: 71%

Maintenance and growth requirements in the metabolism of Debaryomyces hansenii performing xylose‐to‐xylitol bioconversion in corncob hemicellulose hydrolyzate

Rivas

Torre

Domínguez

et al. 2008

Biotech & Bioengineering

Self Cite

View full text Add to dashboard Cite

In order to improve the biotechnological production of xylitol, the metabolism of Debaryomyces hansenii NRRL Y-7426 in corncob hemicellulose hydrolyzate has been investigated under different conditions, where either maintenance or growth requirements predominated. For this purpose, the experimental results of two sets of batch bioconversions carried out alternatively varying the starting xylose concentration in the hydrolyzate (65.6 < or = S(0) < or = 154.7 g L(-1)) or the initial biomass level (3.0 < or = X(0) < or = 54.6 g(DM) L(-1)) were used to fit a metabolic model consisting of carbon material and ATP balances based on five main activities, namely fermentative assimilation of pentoses, semi-aerobic pentose-to-pentitol bioconversion, biomass growth on pentoses, catabolic oxidation of pentoses, and acetic acid and NADH regeneration by the electron transport system. Such an approach allowed separately evaluating the main bioenergetic constants of this microbial system, that is, the specific rates of ATP and xylose consumption due to maintenance (m(ATP) = 21.0 mmol(ATP) C-mol(DM) (-1)h(-1); m(Xyl) = 6.5 C-mmol(Xyl) C-mol(DM) (-1)h(-1)) and the true yields of biomass on ATP (Y(ATP) (max) = 0.83 C-mol(DM) mol(ATP) (-1)) and on xylose (Y(Xyl) (max) = 0.93 C-mol(DM) C-mol(Xyl) (-1)). The results of this study highlighted that the system, at very high S(0) and X(0) values, dramatically increased its energy requirements for cell maintenance, owing to the occurrence of stressing conditions. In particular, for S(0) > 130 g L(-1), these activities required an ATP consumption of about 2.1 mol(ATP) L(-1), that is, a value about seven- to eightfold that observed at low substrate concentration. Such a condition led to an increase in the fraction of ATP addressed to cell maintenance from 47% to 81%. On the other hand, the very high percentage of ATP addressed to maintenance (> 96%) at very high cell concentration (X(0) > or = 25 g(DM) L(-1)) was likely due to the insufficient substrate to sustain the growth.

show abstract

Section: Influence Of Acetic Acid On the Energetic Metabolismsupporting

confidence: 71%

Maintenance and growth requirements in the metabolism of Debaryomyces hansenii performing xylose‐to‐xylitol bioconversion in corncob hemicellulose hydrolyzate

Rivas

Torre

Domínguez

et al. 2008

Biotech & Bioengineering

Self Cite

View full text Add to dashboard Cite

show abstract

“…The concentration of sulfuric acid, the temperature, and the residence time, variables reported to influence the hydrolysis of different lignocellulosic materials [6,7,9,25,31,36], were varied according to a central composite full factorial design.…”

Section: Resultsmentioning

confidence: 99%

A study on the pretreatment of a sugarcane bagasse sample with dilute sulfuric acid

Canilha

Santos

Rocha

et al. 2011

J Ind Microbiol Biotechnol

Self Cite

171

View full text Add to dashboard Cite

Experiments based on a 2(3) central composite full factorial design were carried out in 200-ml stainless-steel containers to study the pretreatment, with dilute sulfuric acid, of a sugarcane bagasse sample obtained from a local sugar-alcohol mill. The independent variables selected for study were temperature, varied from 112.5°C to 157.5°C, residence time, varied from 5.0 to 35.0 min, and sulfuric acid concentration, varied from 0.0% to 3.0% (w/v). Bagasse loading of 15% (w/w) was used in all experiments. Statistical analysis of the experimental results showed that all three independent variables significantly influenced the response variables, namely the bagasse solubilization, efficiency of xylose recovery in the hemicellulosic hydrolysate, efficiency of cellulose enzymatic saccharification, and percentages of cellulose, hemicellulose, and lignin in the pretreated solids. Temperature was the factor that influenced the response variables the most, followed by acid concentration and residence time, in that order. Although harsher pretreatment conditions promoted almost complete removal of the hemicellulosic fraction, the amount of xylose recovered in the hemicellulosic hydrolysate did not exceed 61.8% of the maximum theoretical value. Cellulose enzymatic saccharification was favored by more efficient removal of hemicellulose during the pretreatment. However, detoxification of the hemicellulosic hydrolysate was necessary for better bioconversion of the sugars to ethanol.

show abstract

“…Many of these processes have been modified, improved, and optimized in the last decade [78][79][80][81][82][83][84][85][86][87][88][89]. Sulfuric acid and hydrochloric acid are the most widely researched catalysts for both concentrated and dilute acid hydrolysis processes, but other mineral acids as well as organic acids have also been used.…”

Section: Concentrated Acid Hydrolysismentioning

confidence: 99%

“…Higher acid concentrations lead to a higher degree of hydrolysis of hemicellulose, but the ethanol yields resulting from fermentation are lower. In another study, the maximum xylose concentration in the hydrolysate (17.1 g/L) was attained when sugarcane bagasse was treated at 160°C for 60 min using 0.7% of phosphoric acid [88].…”

Section: Dilute Acid Hydrolysismentioning

confidence: 99%

Lignocellulosics as a Renewable Feedstock for Chemical Industry: Chemical Hydrolysis and Pretreatment Processes

O’Hara

Zhang

Doherty

et al. 2011

Green Chemistry for Environmental Remediation

View full text Add to dashboard Cite

Sugarcane bagasse hydrolysis with phosphoric and sulfuric acids and hydrolysate detoxification for xylitol production

Abstract: The effectiveness of phosphoric acid to release xylose from sugarcane bagasse hemicellulose was assessed through a 2^3 full factorial design

Cited by 31 publications

References 14 publications

Maintenance and growth requirements in the metabolism of Debaryomyces hansenii performing xylose‐to‐xylitol bioconversion in corncob hemicellulose hydrolyzate

Maintenance and growth requirements in the metabolism of Debaryomyces hansenii performing xylose‐to‐xylitol bioconversion in corncob hemicellulose hydrolyzate

A study on the pretreatment of a sugarcane bagasse sample with dilute sulfuric acid

Lignocellulosics as a Renewable Feedstock for Chemical Industry: Chemical Hydrolysis and Pretreatment Processes

Contact Info

Product

Resources

About