Dilute Acid Pretreatment Research Articles

Efficient hemicellulose removal from lignocellulose by induced electric field-aided dilute acid pretreatment

This study evaluated the effectiveness of induced electric field (IEF) as a novel electrotechnology to assist dilute acid pretreatment of wheat straw (WS) at atmospheric pressure and low temperature (90 °C). The effects of acid concentration and duration on cellulose recovery, hemicellulose and lignin removal were investigated. Meanwhile, the differences between IEF pretreatment and hydrothermal pretreatment were compared by quantitative and qualitative analysis. The optimal pretreatment condition was acid concentration 1 % with the period of 5 h. Under the parameters, the hemicellulose removal of WS after IEF pretreatment was up to 73.6 %, and the enzymatic efficiency was 55.8 %. In addition, the irregular surface morphology, diminished functional groups associated with hemicellulose, increased specific surface area and pore volume, as well as improved thermal stability of the residual WS support the remarkable effect of IEF pretreatment. The feasibility of IEF pretreatment is might be due to the fact that the magneto-induced electric field promotes ionization of H+ and formation of hydrated hydrogen ions, increasing the acidity of the medium. Secondly, electroporation disrupts the anti-degradation structure of WS and increases the accessibility of cellulose to cellulases. It indicated that IEF is a green and efficient strategy for assisting the separation of hemicellulose from lignocellulose.

Combination of deep eutectic solvent and diluted acid pretreatments for sugarcane bagasse fractionation

Combination of deep eutectic solvent and diluted acid pretreatments for sugarcane bagasse fractionation

From bulk banana peels to active materials: Slipping into bioplastic films with high UV-blocking and antioxidant properties

Bananas are among the most produced fruits globally, and their industry generates substantial amounts of peels, which are currently underutilized. Therefore, a simple process was proposed to fully convert banana peel powder (BPP) into bioplastic films using mild pretreatments. The influence of the following variables on film performance was investigated: the type of BPP (unblanched versus blanched), the pretreatment solvent (water – i.e., hydrothermal pretreatment, HTP – or sulfuric acid solution – i.e., dilute acid pretreatment, DAP), and the addition or not of carboxymethyl cellulose (CMC) in the films. The tensile properties of the bioplastics were primarily affected by the presence of CMC, with the films containing 20 wt% of this biopolymer achieving a tensile strength up to 16 MPa. The water vapor permeability was not influenced by any of the studied variables. In contrast, the water contact angle was primarily affected by the pretreatment employed, with all films prepared by HTP displaying a hydrophobic surface. The UV-shielding properties of the materials were mainly influenced by the type of BPP, and all films blocked at least 98% of UV radiation. The antioxidant activity was influenced primarily by the type of BPP, as blanching banana peels helped preserve it. These films are, therefore, promising materials for active food packaging applications, which could contribute to a transition toward a circular bioeconomy.

Rapid Dilute Sulfuric Acid Hydrolysis of Soy Flour to Amino Acids for Microbial Processes and Biorefining

Amino acids have relevance in biorefining as fermentation nutrients but also as valued coproducts obtainable from plant biomass. Soy flour was studied as a representative low-cost protein source requiring hydrolysis to free primary amino acids for utilization. Within the context of biorefining, process schemes, reactant concentrations, times, and temperatures were varied to explore the efficiency of dilute sulfuric acid hydrolysis of soy flour to release amino acids. Two process strategies were optimized. Either soy flour was co-processed with switchgrass biomass using a dilute-acid pretreatment, or it was hydrolyzed alone with dilute acid. Significant improvement to hydrolysate fermentability was accomplished by adding 2.5–10 g/L soy flour to switchgrass pretreatment with dilute sulfuric acid (0.936% v/v) for 15 min at 160 °C. This practice optimized accumulation of neutral sugars and resulted in a 25% reduction in furfural while boosting xylose 7% and up to doubling primary amino nitrogen (PAN), as compared to no soy flour addition to switchgrass pretreatment. When soy flour was hydrolyzed alone, PAN titers were optimized to 1588 mg N/L (9.9 g amino acids/L) and yield to 0.0529 g PAN/g flour (61% of theoretical) using a 10% (v/v) (1.8 M) sulfuric acid hydrolysis 30 min at 160 °C.

Potential brewer’s spent grain as a carbon source alternative for biosurfactant production by Rhodotorula mucilaginosa (LBP4)

This study promoted the valorization of brewer’s spent grain (BSG) by using it as an alternative and low-cost carbon source in the production of biosurfactant by Rhodothorula mucilaginosa (LPB4) in an optimized process. The raw BSG was characterized: moisture content (80.0%), insoluble and soluble lignin (29.25%), proteins (6.43%), ash (4.22%), cellulose (47.37%) and pH (6.06), then to verify the increase of reducing sugars, BSG was tested by microwave-assisted alkali and diluted acid pretreatments and then the BSG with and without pretreatment were subjected to enzymatic hydrolysis. The microwave-assisted alkali, followed by enzymatic hydrolysis, achieved 181 mg of sugar.g-1 of BSG and was the most effective. The hydrolysate was used as a carbon source for the biosurfactant production assays and optimized under the following conditions: 30ºC, 120 rpm, 2.5 g.L- 1 of sugar, and pH 4. The biosurfactant was able to emulsify (%E24) different hydrophobic substrates, which were as follows: soybean oil (64.4%), motor oil (62.2%), kerosene (67.4%) and diesel oil (56.81%). Also, it showed stability under extreme temperatures, pH, and salinity. A critical micelle concentration (CMC) of 14.8 mg.mL- 1 was achieved with a decrease in surface tension (ST) from 71.26 mN.m-1 to 30.56 mN.m- 1. The extracted biosurfactant showed an anionic nature and structural similarities to a glycolipid. The present findings revealed that pretreated BSG may be used as a substrate in biosurfactant production using the yeast R. mucilaginosa. This is the first study regarding using LBP4 to optimize the production of biosurfactant using alkali enzymatic BSG hydrolysate.

Sustainability assessment of lignocellulosic biorefineries based on sequential pretreatments

AbstractBACKGROUNDPretreatments are critical in biorefinery analysis, affecting further reactions and downstream processes. However, most pretreatments are studied and optimized as single‐step schemes, focusing on maximizing a side stream. Sequential pretreatments have been shown to improve the selective isolation of platforms for further valorization. However, pretreatment performance can consider not only technical but also economic, environmental, and social concerns. This work assessed the sustainability of sequential pretreatments in rice husk‐based biorefineries.RESULTSFour biorefinery scenarios were designed, simulated, and assessed considering dilute acid and wet air oxidation pretreatment technologies in sequential and single‐step schemes. Economic feasibility was demonstrated for sequential pretreatments when phenolic compounds are contemplated, generating gross incomes of 4.76 M‐USD yr−1. From an environmental perspective, the rice supply chain generated a carbon footprint of 2.17 kg CO2 eq kg−1 of rice husks, where the producer link is the largest contributor due to fertilizer use. Likewise, it was shown that supplying energy demands using black liquor as fuel relieves operating costs and reduces the carbon footprint. The social dimension showed that between 69 and 77 jobs could be generated annually along the value chain and the biorefinery schemes. However, biorefineries have a high risk due to the high volume of cooling water.CONCLUSIONSAll dimensions were weighted to calculate a sustainability index, where it was concluded that sequential pretreatment biorefineries improved sustainability against the single‐step schemes. However, the scenario of valorization of the three fractions (Sc1) is the best scheme to be implemented as it has always demonstrated economic feasibility. © 2023 Society of Chemical Industry (SCI).

A comparative study between the conventional and advanced biomass pretreatment methods applied on the Napier Grass used as a biomass

This paper presents a comparative analysis of the traditional and advanced pretreatment methods on the Napier Grass used as a biomass. It is a perennial C-4 type grass belongs to a sugarcane family, also called as Pennisetum Purpureum. It is found in abundance all across the world and traditionally used as a cattle feed stock in India.The author made an attempt for better effectiveness of the Napier Grass processing towards better productivity by using various pretreatment methods viz: Spectrophotometry, High Performance Liquid Chromatography, Enzyme Hydrolysis and Sonication.Napier Grass has lignocellulosic fibers with structural carbohydrates that requires pretreatment and enzymatically saccharified before they fermented into monomeric sugars and biofuel. The experimentation is carried out to examine the release of structural carbohydrate from Napier Grass using dilute acid pretreatment. In order to accelerate the process, the protein-rich fungus biomass Rhizopus Oligosporus has been added to the crude Napier Grass juice.It has been observed that, if green processed Napier Grass is treated with 5% concentrated sulfuric acid for a time span of 45 min at 120 °C, that results to yield the highest concentration of glucose from hemicellulose and cellulose with the highest quantum of xylose.The experimental result shows an increase in monomeric sugar that released from Napier Grass fibers after enzymatic saccharification process and the xylose and glucose concentrations achieved to 85.5% by dry weight of Napier grass.

Insight into key obstacles and technological strategy for enzymatic digestion of full cellulose fraction from poplar sawdust

Lignocellulosic biomass mainly consists of hemicellulose, lignin, and cellulose, which differently affect the enzymatic digestibility of cellulose. As for the typical representative for inert woody biomass, three components of cellulose were proposed conceptually for poplar sawdust, i.e., active cellulose, inert cellulose, and resistant cellulose. Dilute sulfuric acid pretreatment, hydrogen peroxide-sulfuric acid delignification, and sulfuric acid-assisted glycerol swelling were, respectively, proven to break the three obstacle mechanisms that affect the cellulase of poplar. The removal of key obstacles improved the cellulase digestibility of poplar enzyme-hydrolyzed residues by 188.7 %, and glucose yield increased from 34.6 % to 99.9 %. Therefore, a total of 39.5 g glucose was obtained from 100 g poplar sawdust by integrating the above three technologies. This work presented insight into and removed the key obstacles to enzymatic digestibility of poplar cellulose and developed an integrated technology to effectively convert full cellulose fraction to glucose from woody biomass.

Highly-efficient lipid production from hydrolysate of Radix paeoniae alba residue by oleaginous yeast Cutaneotrichosporon oleaginosum

Valorization of herbal extraction residues (HERs) into value-added products is pivotal for the sustainability of Chinese medicine industry. Here, seven different enzymatic hydrolysates of dilute acid pretreated HERs were evaluated for lipid production by Cutaneotrichosporon oleaginosum. Among them, the highest sugar yield via hydrolysis and the maximum lipid production were obtained from Radix paeoniae alba residue (RPAR). More interestingly, high proportion of sugar polymers was disintegrated into fermentable sugars during the pretreatment step, allowing a cheap non-enzymatic route for producing sugars from RPAR. A repeated dilute acid pretreatment gained a high sugar concentration of 241.6 g/L through reusing the pretreatment liquor (PL) for four times. Biomass, lipid concentration, and lipid content achieved 49.5 g/L, 35.7 g/L and 72.2 %, respectively, using fed-batch culture of PL. The biodiesel parameters indicated lipids produced from HERs were suitable for biodiesel production. This study offers a cost-effective way to upgrade the HERs waste into micro-biodiesel.

Bio-based succinic acid production from durian husk: A rising Southeast Asia agricultural waste

The spiking availability of durian husk in Southeast Asia reveals a promising yet underutilized lignocellulosic biomass. Compositional characterization via National Renewable Energy Laboratories protocols (NREL) showed that durian husk contained 40.96% glucan, 9.51% xylan, and 26.48% of lignin. Enzymatic hydrolysis of durian husk was improved upon dilute sulfuric acid pretreatment. The optimal conditions for particle size and pretreatment duration were determined to be − 80/+ 100 mesh size durian husk exposing to an hour of acid pretreatment, resulting in a maximum reducing sugar recovery of 37.29 and 24.32 g/L for acid and enzyme hydrolysate, respectively. Fermentability tests using Actinobacillus succinogenes 130Z for both acid and enzyme hydrolysates demonstrated succinic acid yields of 49% and 63% (g/g), respectively. A stoichiometry equation describing the formation of substrate and all products was established based on the results obtained from batch fermentation: C6H12O6 + 0.377 C5H10O5 + 0.130NH3 + 0.238CO2 → 0.864 C4H6O4 + 0.224 C2H4O2 + 0.134CH2O2 + 0.292CH2.096O0.111N0.658 + 0.231 H2O. This equation serves as a useful reference for future investigations into succinic acid production reactions. The cost-effectiveness of succinic acid production and its environmental performance were evaluated to highlight the potential of durian husk as feedstock. This study presents the first report on the utilization of durian husk as an alternative and sustainable feedstock for the production of bio-based succinic acid.

Enhanced Enzymatic Sugar Recovery of Dilute-Acid-Pretreated Corn Stover by Sodium Carbonate Deacetylation.

The prehydrolysate from dilute acid pretreatment of lignocellulosic feedstocks often contains inhibitory compounds that can seriously inhibit the subsequent enzymatic and fermentation processes. Acetic acid is one of the most representative toxic compounds. In this research, alkaline deacetylation of corn stover was carried out using sodium carbonate under mild conditions to selectively remove the acetyl groups of the biomass and reduce the toxicity of the prehydrolysate. The deacetylation process was optimized by adjusting factors such as temperature, treatment time, and sodium carbonate concentration. Sodium carbonate solutions (2~6 wt%) at 30~50 °C were used for the deacetylation step, followed by dilute acid pretreatment with 1.5% H2SO4 at 121 °C. Results showed that the acetyl content of the treated corn stover could be reduced up to 87%, while the hemicellulose loss remained low. The optimal deacetylation condition was found to be 40 °C, 6 h, and 4 wt% Na2CO3, resulting in a removal of 80.55% of the acetyl group in corn stover and a hemicellulose loss of 4.09%. The acetic acid concentration in the acid prehydrolysate decreased from 1.38 to 0.34 g/L. The enzymatic hydrolysis of solid corn stover and the whole slurry after pretreatment increased by 17% and 16%, respectively.

Enhanced reducing sugar production and extraction for Chlorella vulgaris in mixotrophic cultivation using high hydrostatic pressure processing and ultrasound

ABSTRACT Although extraction of polysaccharides to convert reducing sugars (RS) from microalgae by acid or alkali pretreatments and enzymatic hydrolysis has been extensively studied, few reports exploring the use of high hydrostatic pressure processing (HHP) and ultrasonication (US) as emerging technologies for the extraction of sugars from microalgae biomass exist. Thus, the present study was conducted to determine the effects of mixotrophic growth and stress conditions (NaNO3 and CO2 concentration and light intensity) on RS and protein accumulation in the unicellular green alga Chlorella vulgaris in addition to optimization of the effectiveness of the sequential applications of HHP and US with dilute acid as well as simultaneous enzymatic saccharification on the production of RS from microalga cells. High light intensity, high CO2 concentration and limited nitrogen concentration promoted RS production. The maximum protein content (0.0683 mg g‒1) was achieved at 0.3 g l‒1 NaNO3 concentration, 7000 μmol photons m‒2 s‒1 and 6 l min‒1 CO2 concentration. The highest RS content of C. vulgaris after 48 h enzymatic saccharification (583.86 ± 13.23 mg g‒1) was obtained at 1% (w/w) acid concentration and 80% amplitude for 30 min with 79.4% RS yield. Combined US-assisted dilute acid pretreatment and enzymatic hydrolysis were also found to be more effective than HHP assisted dilute acid pretreatment and enzymatic saccharification. Therefore, microalgal biomass can be considered a suitable renewable feedstock used in fermentation.

Evaluation and Optimization of the Different Process Parameters of Mild Acid Pretreatment of Waste Lignocellulosic Biomass for Enhanced Energy Procreation.

The screening and evaluation of different waste lignocellulosic biomasses to meet the ever-increasing energy demand, from the widely available waste lignocellulosic biomasses evaluated. For the current study, peanut shell biomass is considered for energy procreation. However, the energy content of biomass is still lesser as compared to conventional fossil fuels like coal and petroleum. The dilute acid pretreatment has been proven to improve the energy content of the lignocellulosic biomasses to a significant extent. Various pretreatment process parameters have been reported to have different degrees of impact on the betterment of energy procreation. Among various types of pretreatments, dilute acid pretreatment holds notable cognizance. Accordingly, the current manuscript is to evaluate the impact of various pretreatment process parameters (time, temperature, acid concentration, mass:liquor ratio, and particle size which were defined through an exhaustive literature search) for improving the energy recovery potential. The obtained results indicated notable changes in the devolatilization characteristics of the biomass as a result of pretreatment, thereby resulting in the upgradation of the fuel properties. A sustainability investigation has been carried out to point out the efficacy of the optimized pretreatment of biomass in terms of environmental sustainability and was also compared with the raw variant (untreated form of biomass). The proposed scheme of study will definitely be beneficial toward the mitigation of the energy crisis in the state of Jharkhand.

Construction and exploration of a dilute acid pretreatment dataset on poplar wood to propose trade-offs of chemicals evolution

This work provides one of the most comprehensive datasets to date on the chemical evolution of poplar wood polysaccharides and their degradation products during dilute acid pretreatment. Based on the literature, an unprecedented set of 38 conditions was generated using a design of experiment approach within the following parameter ranges: 2–60 min, 120–190 °C, 0–4%wt H2SO4. Solid wood residues and pretreatment liquid, recovered separately, were analyzed for no less than 12 compounds: sugars, inhibitors, and lignin. Particular attention was paid to the sampling and method description so that the dataset, fully available, can be easily shared and reused. This unique dataset was explored using models to follow the evolution of each chemical species. A more original and in-depth analysis was carried out by combining the models using desirability functions, which enabled us to propose trade-offs between the evolution of the different compounds according to the targeted production objectives.

Long term study of cell wall saccharification and high added value phenolic acids production from Phalaris aquatica L. energy crop

Phalaris aquatica L. is a cool-season perennial grass of the Mediterranean that has been used for forage production, while recently was identified as a novel candidate for sustainable second-generation bioethanol production. This study provides for the first time evidence about this energy crop long-term performance (five years of growth), the cell wall saccharification efficiency and the production of high added value compounds during this period. High biomass production was recorded constantly after the first year of plant growth, with a maximum of 22.4 ± 0.5 t of dry mass (DM) per ha and stable structural polysaccharides concentration 68.8% ± 0.8 w/w DM from the third year on. Independently from crop age, dilute acid pretreatment (120 °C, 1.5% H2SO4, 45 min) promoted the subsequent enzymatic hydrolysis of P. aquatica L. biomass. The dilute acid pre-treatment positive effect is attributed both to the hemicellulose solubilization and the breakage of intermolecular bonds between polysaccharides and phenolic acids, as supported by the present study results These combined acid/enzymatic hydrolysis processes were able to convert more than 80% of cell wall polysaccharides into fermentable sugars, releasing simultaneously a substantial amount of phenolic acids of 2.16% ± 0.48 w/w DM. The ratio of ferulic to p-coumaric acid in the acid hydrolysate can be used for the prediction of the subsequent cellulose enzymatic saccharification efficiency, by the model described here. The protocatechuic acid, which can find many technological applications, was the main bioactive polyphenol in the final hydrolysate with concentration ∼1% w/w DM. These results are supportive of Phalaris aquatica L. suitability as a sustainable biorefinery crop, under the semi-arid Mediterranean climatic conditions contributing to this region biodiversity and prosperity.

Life cycle assessment of fermentative xylitol production from wheat bran: A comparative evaluation of sulphuric acid and chemical-free wet air oxidation-based pretreatment

Xylitol, a sugar alcohol is a low-calorie sweetener has wide applications in food and pharmaceutical industry and hence considered as a high value premium product. The conventional methods for fermentative xylitol production uses chemicals (acid/alkali) which generates inhibitors affecting fermentation and downstream purification of xylitol. In the present study, wet air oxidation was evaluated as a chemical-free pretreatment option of wheat bran for xylose release which is subsequently fermented to xylitol. Life cycle assessment was used as a tool to compare wet air oxidation with conventional methods like dilute acid pretreatment for valorization of wheat bran, a model agro-industrial remnant. A comparative evaluation of wet air oxidation and dilute acid pretreatment was investigated for fermentative production of xylitol (1 g/L as functional unit) with the aim of identifying the process involved with the lowest environmental impact, while also demonstrating the higher xylose recovery of 13.52 g/L coupled with FO based concentration unit. The inputs and outputs of the process involving energy use, chemicals employed, and emissions produced were evaluated with respect to food and environment perspective. Environmental impacts of wet air oxidation and dilute acid pretreatment with fermentative xylitol production of 6.134 and 1.42 g/L, respectively showed emission results of 1.476 and 5.288 kg CO2 equivalent, respectively. Though, primary energy demand of wet air oxidation was almost found to be equivalent to dilute acid, due to energy penalty for reactor mixing was higher in wet air oxidation. However, energy demand of wet air oxidation-based pretreatment was found to be energy efficient by 30% as compared to dilute acid. Coupling biogas reduces energy demand by 3.5%. The reduction in impacts relevant to food safety namely, marine aquatic and freshwater ecotoxicity potential were found by 74.29% and 84.97% substantially lower in wet air oxidation as compared to dilute acid based xylitol production. The effect of sulphate, as input form of sulphuric acid in dilute acid showed an impact of 3.83 folds higher on human toxicity potential as compared to wet air oxidation pretreatment process.

Economic viability of two-stage biohydrogen and biomethane production from cassava stillage residue focusing on solids content and pretreatment

Biohythane (a mixture of hydrogen and methane) may play a significant role in a future decarbonised energy system. The production of biohythane can be achieved by sequential dark hydrogen fermentation and anaerobic digestion. However, the technology readiness level of biohythane can be limited by many process constraints negatively affecting its commercial feasibility. Here, a pilot experiment on fermentative hythane production from cassava stillage residue (CSR) incorporating dilute acid pretreatment and enzymolysis was undertaken. The production of hydrogen and methane was 72.0 ± 10.7 and 295.4 ± 28.5 mL/g volatile solid, respectively. Different scenarios for techno-economic analysis were developed in terms of the dried/wet form of CSR and total solids content during fermentation. Results suggested that hythane from CSR was not economically feasible with a high production cost (1.39–2.33 €/m3). There was a trade-off relationship between the increase in methane yield through pretreatment and the associated cost.

Integrated strategies for furfural production and lignocellulose fractionation in aqueous deep eutectic solvents

The current biomass refinery pretreatment using deep eutectic solvents (DES) has primarily focused on downstream utilization of cellulose and lignin, while often overlooking the potential of hemicellulose. Herein, an innovative and integrated strategy was proposed for simultaneous production of furfural (FF) and fractionation of lignin and cellulose from biomass using the same aqueous DES. To achieve this goal, response surface methodology (RSM) was employ to optimize the dilute hydrochloric acid (HA) pretreatment of corn stover, a representative of lignocellulosic material, ensuring complete removal of hemicellulose. The resulting hemicellulose hydrolysate was then efficiently converted into FF in aqueous DES system, achieving an impressive yield of 72.82 %. By introducing MgCl2 as a catalyst, the FF yield soared to an exceptional 86.94 %. Furthermore, a plausible mechanism was elucidated for the conversion of hemicellulose to FF in the aqueous DES. Concurrently, the solid residue resulting from the dilute HA pretreatment was fractionated using the same aqueous DES, successfully extracting cellulose and lignin fractions. Notably, the separated cellulose solid residue exhibited an outstanding digestion efficiency of 96.3 % after 72 h of enzymatic hydrolysis at 30 FPU/g, as confirmed through meticulous FTIR analyses. In addition, an advanced 2D-HSQC NMR technique was utilized to unveil the intricate structure of the obtained lignin, revealing a guaiacol-syringyl-p-hydroxyphenyl (G-S-H) type lignin enriched with abundant CH3O- and β-O-4 linkages. A mass balance analysis showed the production of 14.0 g FF, 31.9 g glucose and 14.2 g lignin from 100 g dry corn stover. This state-of-the-art approach presented not only pioneers a novel avenue for the concurrent production of FF but also offers a sustainable and eco-friendly method for the fractionation of lignin and cellulose using DES solvents.

Production of optical pure L-lactic acid from Cabernet Sauvignon grape pomace by engineered Lactiplantibacillus plantarum

Cabernet Sauvignon grape pomace contains carbohydrates and various amino acids that could be used as substrates for lactic acid (LA) production. In this study, a mutant strain of L. plantarum with deletion of the D-lactate synthesis gene was developed and used to produce optical pure L-LA from grape pomace. The highest optical purity of the L-LA produced by this mutant strain was 99.61%. The direct bioconversion of the raw substrate showed a low LA yield. Several pretreatment methods were applied to improve the LA yield, including ball milling, hydrothermal, dilute acid pretreatment, alkaline pretreatment, and combined wet alkaline mechanical pretreatment. Due to the efficient delignification, alkaline pretreatment achieved the highest lactic acid yield of 96.26% at 15% solid loading, with corresponding LA concentration and volumetric productivity of 18.45 g/L and 2.30 g/L·h, respectively.

Fermentable sugars production by dilute acid pretreatment of sugarcane leaves with minimum sugar degradation products

Fermentable sugars production by dilute acid pretreatment of sugarcane leaves with minimum sugar degradation products