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We examine feedstock cost and minimum selling price for ethanol production from corn stover as a function of scale, stover yield, participation rate, and price incentives for two conversion technologies: a conventional base case featuring thermochemical pretreatment with added cellulase, and an advanced case featuring consolidated bioprocessing with cotreatment (C‐CBP). Delivered feedstock cost ranged from $85 Mg−1 at small (10 million gallons year−1 or ~38 million L year−1) scale with high yield and participation rates to $124 Mg−1 at large scale (60 million gallons year−1 or 227 million L year−1) and low yield and participation rates. The minimum ethanol selling price (MESP) was approximately twofold lower for the advanced case compared with the base case. The payback period was several times lower for the advanced case compared with the base case, with increasing disparity at smaller scales, and was highly sensitive to ethanol price supports. For both C‐CBP and the conventional processing paradigm, MESP decreased with increasing scale, indicating that the cost penalty due to higher feedstock transport distances was more than outweighed by lower capital costs. However, the cost penalty for operation at small scale, expressed in $ gallon−1 ethanol, is lower for C‐CBP than for the conventional paradigm by roughly twofold. Particularly for initial applications of C‐CBP, we speculate that this cost penalty will likely be modest compared with the anticipated benefits of small‐scale operation such as increased opportunity to use existing infrastructure, easier plant siting and supply chain establishment, and lower total investment required. [ABSTRACT FROM AUTHOR]

A high‐quality filler within mixed matrix membranes, coupled with uniform dispersity, endows a high‐efficiency transfer pathway for the significant improvement on separation performance. In this work, a zeolite‐typed MCM‐22 filler is reported that is doped into polydimethylsiloxane (PDMS) matrix by ultrafast photo‐curing technique. The unique structure of nanosheets assembly layer by layer endows the continuous transfer channels towards penetrate molecules because of the inter‐connective nanosheets within PDMS matrix. Furthermore, an ultrafast freezing effect produced by fast photo‐curing is used to overcome the key issue, namely filler aggregation, and further eliminates defects. When pervaporative separating a 5 wt% ethanol aqueous solution, the resulting MCM‐22/PDMS membrane exhibits an excellent membrane flux of 1486 g m−2 h−1 with an ethanol separation factor of 10.2. Considering a biobased route for ethanol production, the gas stripping and vapor permeation through this membrane also shows a great enrichment performance, and the concentrated ethanol is up to 65.6 wt%. Overall, this MCM‐22/PDMS membrane shows a high separation ability for ethanol benefited from a unique structure deign of fillers and ultrafast curing speed of PDMS, and has a great potential for bioethanol separation from cellulosic ethanol fermentation. [ABSTRACT FROM AUTHOR]

Lignocellulosic biomass, the most abundant natural resource on earth, can be used for cellulosic ethanol production but requires a pretreatment to improve enzyme access to the polymeric sugars while obtaining value from the other components. γ‐Valerolactone (GVL) is a promising candidate for biomass pretreatment since it is renewable and bio‐based. In the present work, the effect of a pretreatment based on GVL on the enzymatic saccharification of white birch was evaluated at a laboratory scale and the importance of the washing procedure for the subsequent saccharification was demonstrated. Both the saccharification yield and the production of cellulosic ethanol were higher using a noncommercial enzyme crude from Talaromyces amestolkiae than with the commercial cocktail Cellic CTec2 from Novozymes. Furthermore, the production of extracellular cellulases by T. amestolkiae has been optimized in 2 L bioreactors, with improvements ranging from 40% to 75%. Finally, it was corroborated by isoelectric focus that optimization of cellulase secretion by T. amestolkiae did not affect the pattern production of the main β‐glucosidases and endoglucanases secreted by this fungus. [ABSTRACT FROM AUTHOR]

Three delignification treatments of corncob residues (CCR), including NaOH, formic acid, and sulfite treatments, were compared at the respective optimized condition and in light of chemical compositions, sugar recovery, and ethanol production. NaOH and sulfite treatment can remove lignin in the CCR efficiently. Though NaOH treatment showed a superior ability of delignification, its solid cellulose recovery is lower than that of sulfite treatment. The sulfite treatment has the highest selectivity between delignification and cellulose conservation. The formic acid-treated CCR still had high lignin contents because formic acid also accelerated the solvation of cellulose. In fed-batch simultaneous saccharification and fermentation (SSF) with 25% substrate loading, the highest 77.1 ± 2.33 g/L ethanol was from NaOH-treated CCR, corresponding to a CCR-to-ethanol yield of 0.208 ± 0.0021 g/g. However, the sulfite pretreated CCR also produced 68.2 ± 2.22 g/L ethanol, with a higher CCR-to-ethanol yield of 0.219 ± 0.0012 g/g. The high substrate dosage is beneficial to ethanol concentration but not beneficial to CCR-to-ethanol yield. The optimal substrate dosage required for ethanol production depends on the targeted aim (ethanol concentration or CCR-to-ethanol yield). [ABSTRACT FROM AUTHOR]

While the industry has produced sugar-derived ethanol from the conventional method of fermentation for hundreds of years, other effective routes involving the direct transformation of carbohydrates still remain extremely rare. Very recently, an innovative chemo-catalytic method driven by the aqueous-phase catalysis was created for the synthesis of cellulosic ethanol, making a great breakthrough in the common ways as it can theoretically utilize all of the carbon atoms in sugars with faster kinetics; up to now, results from the relevant studies have been accumulated to a certain extent, but the periodic conclusions in this field are unfortunately absent. For this reason, this work tries to offer an overview of the cellulosic ethanol produced by chemo-catalytic routes, highlighting the present knowledge in relation to the technical efficiency, catalytic mechanisms as well as practical applications. At first, the advanced progress on the increasing efficiency from a varied type of catalytic systems are extensively discussed, which involves the specific functions of hybrid components from different strategies; meanwhile, the general influences of processing conditions, such as the hydrothermal severity and aqueous environments, are also identified. Subsequently, possible mechanisms behind the chemo-catalytic processes are widely elaborated by analyzing a number of experimental cases associated with the reaction network and its kinetic models. After that, the actual effects of this technique on the real biomass are collected to identify the positive/negative interactions between multiple components, together with the potential solutions on the semi-continuous processes of pilot scale application. The techno-economic analysis (TEA) is also calculated and compared with other similar methods, such as fermentation and gasification. Finally, several proposals aimed at upgrading the whole chain of chemo-catalytic processes are clearly provided, which may function as a guideline for future studies on the production of bio-ethanol from lignocellulosic materials. [ABSTRACT FROM AUTHOR]

This work investigated the influence of pretreatment methods (using sulfuric acid, sodium hydroxide, or calcium hydroxide) on the characteristics of biochar prepared from residues generated by lignocellulosic ethanol production. As a result, the biochar prepared from the residue of an acid pretreatment-based process showed better thermal stability than the other two biochars. The weight loss rates of three kinds of biochar at 900 °C were 17.85%, 30.95%, and 36.76%. The specific surface areas of the three biochars were 3.03 m2/g, 1.24 m2/g, and 8.04 m2/g, respectively, with the largest specific surface area found on the biochar of calcium hydroxide pretreatment-based process. FTIR analysis showed that the types of surface functional groups of the biochars were basically the same. The maximum theoretical adsorption capacities of the three biochars for methylene blue were 37.3 mg/g, 48.7 mg/g, and 58.2 mg/g, respectively. The adsorption capacity of biochar from alkali pretreatment for methylene blue was significantly better than that from acid pretreatment. The overall results showed that the properties of biochars prepared from fermentation residues under different pretreatment methods were quite different. [ABSTRACT FROM AUTHOR]

Biofuel production from lignocellulose feedstocks is sustainable and environmentally friendly. However, the lignocellulosic pretreatment could produce fermentation inhibitors causing multiple stresses and low yield. Therefore, the engineering construction of highly resistant microorganisms is greatly significant. In this study, a composite functional chimeric cellulosome equipped with laccase, versatile peroxidase, and lytic polysaccharide monooxygenase was riveted on the surface of Saccharomyces cerevisiae to construct a novel yeast strain YI/LVP for synergistic lignin degradation and cellulosic ethanol production. The assembly of cellulosome was assayed by immunofluorescence microscopy and flow cytometry. During the whole process of fermentation, the maximum ethanol concentration and cellulose conversion of engineering strain YI/LVP reached 8.68 g/L and 83.41%, respectively. The results proved the availability of artificial chimeric cellulosome containing lignin-degradation enzymes for cellulosic ethanol production. The purpose of the study was to improve the inhibitor tolerance and fermentation performance of S. cerevisiae through the construction and optimization of a synergistic lignin-degrading enzyme system based on cellulosome. [ABSTRACT FROM AUTHOR]

The economical and efficient commercial production of second-generation bioethanol requires fermentation microorganisms capable of entirely and rapidly utilizing all sugars in lignocellulosic hydrolysates. In this study, we developed a recombinant Saccharomyces cerevisiae strain, BLH510, through protoplast fusion and metabolic engineering to enhance its ability to co-ferment glucose, xylose, cellobiose, and xylooligosaccharides while tolerating various inhibitors commonly found in lignocellulosic hydrolysates. The parental strains, LF1 and BLN26, were selected for their superior glucose/xylose co-fermentation capabilities and inhibitor tolerance, respectively. The fusion strain BLH510 demonstrated efficient utilization of mixed sugars and high ethanol yield under oxygen-limited conditions. Under low inoculum conditions, strain BLH510 could completely consume all four kinds of sugars in the medium within 84 h. The fermentation produced 33.96 g/L ethanol, achieving 84.3% of the theoretical ethanol yield. Despite the challenging presence of mixed inhibitors, BLH510 successfully metabolized all four sugars above after 120 h of fermentation, producing approximately 30 g/L ethanol and reaching 83% of the theoretical yield. Also, strain BLH510 exhibited increased intracellular trehalose content, particularly under conditions with mixed inhibitors, where the intracellular trehalose reached 239.3 mg/g yeast biomass. This elevated trehalose content contributes to the enhanced stress tolerance of BLH510. The study also optimized conditions for protoplast preparation and fusion, balancing high preparation efficiency and satisfactory regeneration efficiency. The results indicate that BLH510 is a promising candidate for industrial second-generation bioethanol production from lignocellulosic biomass, offering improved performance under challenging fermentation conditions. Our work demonstrates the potential of combining protoplast fusion and metabolic engineering to develop superior S. cerevisiae strains for lignocellulosic bioethanol production. This approach can also be extended to develop robust microbial platforms for producing a wide array of lignocellulosic biomass-based biochemicals. [ABSTRACT FROM AUTHOR]

Saccharum is relatively new to 33° N latitude. S. spontaneum readily hybridizes with commercial sugarcane (Saccharum spp.) and lends cold tolerance and greater yield to the hybrid progeny, called energycane. Since 2007, there have been numerous new hybrid and backcross energycane genotypes developed but there is a paucity of information about them. Twenty energycane genotypes were tested in the first season of growth from cane propagules (plant cane; PC) against Ho 02-113 (a control) for two site-years in northcentral Mississippi. Grand (exponential) growth continued into October. The prevailing paradigm is that tonnage is what matters. Except for percentage cellulose, all factors tested (dry matter yield, extractable juice volume, °Brix, theoretical ethanol from fermentation, theoretical ethanol from cellulose, and total theoretical ethanol) were greater from the second site-location compared to the first. Dry matter yield (DMY) and total theoretical ethanol yield (TTEY) were moderately correlated. Over the two years of this test only Ho 14-9213 exceeded in mean DMY of Ho 02-113. Sixteen of the 19 test genotypes in this test equaled or exceeded the mean TTEY of Ho 02-113. [ABSTRACT FROM AUTHOR]

The pretreatment of lignocellulosic biomass such as Miscanthus grown on marginal agricultural land is very challenging and requires severe conditions to fractionate cell wall polymers for further valorization. The current study aimed to determine organic acid-based mild conditions to pretreat contrasting lignocellulosic Miscanthus genotypes for the efficient fractionation of cell wall components, with special focus on hemicellulose extraction. In doing so, five Miscanthus genotypes were subjected to four different acid treatments (sulfuric acid, oxalic acid, malonic acid, and citric acid) in a vertical high-pressure steam sterilizer. The results demonstrated that, among the organic acids, oxalic acid was identified as the most effective pretreatment solvent for hemicellulose separation, whereas citric acid yielded the highest amount of galacturonic acid, varying from 15 to 17 mg mL−1 across genotypes. One best performing genotype was selected for the enzymatic hydrolysis. Overall, M. floridulus genotypes exhibited the optimal quality traits for efficient bioconversion with second best in terms of ethanol production potential. [ABSTRACT FROM AUTHOR]

The treatment of tumors in developing countries, especially those with poor medical conditions, remains a significant challenge. Herein, a novel solvent‐exchange strategy to prepare adhesive hydrogels for the concurrent treatment of tumors through synchronous ethanol ablation and local chemotherapy is reported. First, a poly (gallic acid‐lipoic acid) (PGL) ethanol gel is prepared that can undergo solvent exchange with water to form a hydrogel in situ. PGL ethanol gel deposited on the wet tissue can form a hydrogel in situ to effectively repel interfacial water and establish a tight contact between the hydrogel and tissue. Additionally, the functional groups between the hydrogels and tissues can form covalent and non‐covalent bonds, resulting in robust adhesion. Furthermore, this PGL ethanol gel demonstrates exceptional capacity to effectively load antitumor drugs, allowing for controlled and sustained release of the drugs locally and sustainably both in vitro and in vivo. In addition, the PGL ethanol gel can combine ethanol ablation and local chemotherapy to enhance the antitumor efficacy in vitro and in vivo. The PGL ethanol gel‐derived hydrogel shows robust wet bioadhesion, drug loading, sustained release, good biocompatibility and biodegradability, easy preparation and usage, and cost‐effectiveness, which make it a promising bioadhesive for diverse biomedical applications. [ABSTRACT FROM AUTHOR]

Cellulosic ethanol is the key technology to alleviate the pressure of energy supply and climate change. However, the ethanol production process, which is close to industrial production and has a high saccharification rate and ethanol yield, still needs to be developed. This study demonstrates the effective conversion of poplar wood waste into fuel-grade ethanol. By employing a two-step pretreatment using sodium chlorite (SC)-dilute sulfuric acid (DSA), the raw material achieved a sugar conversion rate exceeding 85% of the theoretical value. Under optimized conditions, brewing yeast co-utilizing C6/C5 enabled a yield of 35 g/L ethanol from 10% solid loading delignified poplar hydrolysate. We increased the solid loading to enhance the final ethanol concentration and optimized both the hydrolysis and fermentation stages. With 20% solid loading delignified poplar hydrolysate, the final ethanol concentration reached 60 g/L, a 71.4% increase from the 10% solid loading. Our work incorporates the pretreatment, enzymatic hydrolysis, and fermentation stages to establish a simple, crude poplar waste fuel ethanol process, expanding the range of feedstocks for second-generation fuel ethanol production. [ABSTRACT FROM AUTHOR]

Parthenium hysterophorus (PH), often known as parthenium weed, is one of the seventh most devastating weeds in the world. The primary aim of the study was to produce and optimize fungal FPase enzymes under solid-state fermentation (SSF) conditions for application in enzymatic hydrolysis to produce bioethanol. The impact of various physiological factors was verified through a systematic approach, initially using the one-factor-at-a-time (OFAT) method. Further optimization was carried out using statistical tools by response surface methodology (RSM), selecting three variables, i.e., lactose concentration, peptone concentration, and pH level. The outcomes of this research demonstrated that the RSM-based model led to the optimization of enzyme activity, resulting in 4.08U/ml of FPase, with a lactose concentration of 1.62 %, a peptone concentration of 1.5 %, and a pH level of 6 being the ideal conditions. When employing the FPase enzyme for biomass hydrolysis, the maximum yield of reducing sugar, at 0.37 ± 0.01 g/g, was achieved within a 96-hour period, using enzyme and substrate levels of 30 FPU/100 ml and 3 % (w/v), respectively. Fermentation of enzymatic hydrolysate was carried out by Saccharomyces cerevisiae at 30 °C, pH 6.0, and 120 rpm, which resulted in 0.45g/g ethanol yield after 48 h. Overall, our findings reveal that PH biomass can be introduced into sugar-based biorefineries to produce biofuels and other valuable chemicals.

In this article, the problem of real‐time estimation of the fermentative ethanol process is tackled. The considered observer is a model‐based technique that is robust regarding the model parameter uncertainties and inline noisy measurements. An unstructured kinetic model was used to describe the production of ethanol in a batch bioreactor for Saccharomyces cerevisiae. The biomass concentration was selected as the measured bioreactor´s output via an inline device, where the estimate variables were the substrate and ethanol concentrations. An experimental prototype was constructed to demonstrate the observer's real‐time performance. The experimental results show that the robust, smooth sliding mode observer performs better than the standard proportional sliding mode observer. [ABSTRACT FROM AUTHOR]

Corn and sugarcane are the primary feedstocks for ethanol production, but microbial contamination hinders yeast fermentation efficiency. Current control methods include antibiotics and sulfuric acid, but they have limitations, resulting in dependence on external inputs and the risk of antibiotic-resistant bacteria. This review examines electron beam technology as an industrial-scale disinfection solution for both corn- and sugarcane-based ethanol production, highlighting its advantages, limitations and opportunities for adoption in Brazil. A critical evaluation highlights the importance of optimal operating conditions for scalability, cost effectiveness and sustainable implementation. Through a practical example, we demonstrate the effectiveness of electron beam treatment in improving fermentation efficiency and reducing contamination-related losses. Notably, the ionizing radiation from this process does not affect wort sugar content or generate radioactive residues. While acknowledging the potentially high energy input requirements, cogeneration in sugarcane mills can address this, making it a viable option; however, further technical and economic evaluation should be made. In addition, electron beam technology is a promising approach for the production of high-value products such as neutral alcohol, amino acids, animal feed and pharmaceuticals. Therefore, this comprehensive review provides valuable insights for researchers, industry stakeholders and policymakers to promote sustainable and efficient ethanol production practices. [ABSTRACT FROM AUTHOR]

The sugarcane-driven industry can exemplify sustainable waste management by valorizing its lignocellulosic streams and boosting the rural economy by product diversification. In this aspect, bagacillo is a promising yet untapped carbonaceous feedstock, representing fine fraction of sugarcane bagasse (SCB) with low bulk density. It is used either as a filter aid for juice clarification, when added to mud or mixed with bagasse for cogeneration. This study explores bagacillo for the production of sugars and green chemicals using biochemical platform, with SCB as the benchmark. Its NaOH pretreatment preserved > 90 and > 70% glucan and xylan in solid fraction. Fed-batch hydrolysis with Cellic CTec3 at 1-kg scale liberated 167.4 ± 1.87 and 183.53 ± 1.23 g L−1 monomeric sugars in filtrates of bagacillo and SCB, respectively, in 48 h. Its high-ash content reduced glucan conversion yields by 16%, and led to glucan under-estimation in residual biomass during mass balance closure. Irrespective of feedstock type, within 18 h Saccharomyces cerevisiae MTCC 180 and Pachysolen tannophilus MTCC 1077 produced ~ 5% (v/v) ethanol from 1.5L glucose-rich filtrates, with a ~ 18-fold enhancement in biomass accumulation. However, when Bacillus coagulans NCIM 5648 was assessed for high-temperature 2G lactic acid production, the obtained titer from bagacillo-derived hydrolysate (33.6 ± 1.23 g L−1) was lower than SCB (43.38 ± 1.89 g L−1). The present study demonstrated that bagacillo is an equally amenable bioresource as ~ 506 g fermentable sugar was extracted from 1-kg raw biomass and its glucose-rich fraction showed feasibility for microbial transformation to bio-based platform chemicals. [ABSTRACT FROM AUTHOR]

Sweet sorghum and sweet pearl millet are considered promising alternative feedstocks for bioethanol production. Water soluble carbohydrate (WSC) extraction from the stems for first generation ethanol production is practically well mastered. However, structural carbohydrate (SC) release from the bagasse for cellulosic ethanol production still needs to be more understood and improved, especially for sweet pearl millet. In this study, the effects of two bagasse particle sizes (4.5–9 mm and 1 mm) and two pretreatment solutions (NaOH and H2SO4) at two concentrations (1% and 3%) on the release of SC from sweet sorghum and sweet pearl millet bagasse were investigated. After the extraction of juice, the bagasse pretreatment was carried out at 121 °C for 60 min followed by an enzymatic saccharification. Results indicated that hemicellulose and lignin were better solubilized when the bagasse from both crops was pretreated with NaOH than with H2SO4. The highest glucose concentration (320 and 249 g/kg DM of bagasse for sweet sorghum and sweet pearl millet, respectively) was reached after enzymatic saccharification of the bagasse chopped to 4.5–9 mm particle size and pretreated with 3% NaOH. Under these conditions, cellulose saccharification efficiency reached 88% and 73% for sweet sorghum and sweet pearl millet, respectively, while that of hemicellulose saccharification approached 100% for sweet sorghum and reached 90% for sweet pearl millet. Potential first generation ethanol of 80.3 and 60.7 L/kg DM of biomass and cellulosic ethanol of 138.8 and 115 L/kg DM of biomass were estimated for sweet sorghum and sweet pearl millet, respectively. [ABSTRACT FROM AUTHOR]

У цьому дослідженні порівнюються характеристики газового зондування плівок ZnO та 5% легованих Fe ZnO (Fe-ZnO), синтезованих методом спінового покриття. Рентгенівський аналіз виявив полікристалічну природу спочатку підготовлених плівок, показавши зменшення розміру кристаліту з 25,69 ± 0,95 нм для ZnO до 19,49 ± 0,72 нм для Fe-ZnO. Крім того, введення Fe в ZnO збільшило заборонену зону, при цьому значення змістилися з 3,190 ± 0,105 еВ для ZnO до 3,244 ± 0,147 еВ для Fe-ZnO і зменшили розміри зерен. Зменшення розмірів зерен сприяло збільшенню газової реакції плівки ZnO. Експерименти з зондуванням парів етанолу, проведені в більш широкому діапазоні температур 100-300oC, показують, що найкраща газова реакція плівки Fe-ZnO при 260 oC становить 17,8 ± 0,4, що майже в 1,5 рази більше, ніж у плівки ZnO при тій же температурі. Крім того, варто зазначити, що тонка плівка FeZnO продемонструвала швидшу реакцію та відновлення порівняно з тонкою плівкою ZnO, з часом відгуку та відновлення 32 ± 2 та 162 ± 3 секунди, відповідно, для впливу етанолу 40 ppm. Ці висновки сприяють глибшому розумінню механізмів зондування газу як у тонких плівках ZnO, так і в Fe-ZnO, які є перспективними для майбутніх розробок у технології газових сенсорів. [ABSTRACT FROM AUTHOR]

Biofuels, such as bioethanol, are a clean and sustainable form of energy and have emerged as a viable alternative to fossil fuels. Plant biomass is an important raw material for the production of clean and renewable energy. The holocellulose contained in the composition of plants may be broken down into simple sugars, such as glucose, which are fermented by yeast to produce bioethanol. The conversion of glucose polymers into fermentable sugars is accomplished by enzymes known as holocellulases, which are produced by lignocellulolytic fungi. These enzymes act synergistically for the efficient degradation of cellulose polymers, and the fine and coordinated regulation of this process is performed by transcription factors (TFs). TFs are regulatory proteins that bind to the promoter region of their target genes (CAZymes, sugar transporters, signaling proteins, other TFs, etc.) to induce or repress their transcription. This review aims to understand the main regulatory mechanisms involved in plant biomass degradation by the most studied lignocellulolytic fungi Trichoderma sp., Aspergillus sp., Penicillium sp., and Neurospora crassa. In this context, the most studied TFs related to holocellulose degradation and genetic modification of TFs or promoters as a valuable tool to improve enzyme production for biotechnological purposes have been discussed. This review enables the expansion of knowledge on the regulation of the cellulolytic system of filamentous fungi and the application of this knowledge to the improvement of numerous bioproducts. Engineering TFs and promoters may yield more efficient strains that may be active in plant biomass hydrolysis. In this way, the technological processes for obtaining ethanol from lignocellulose may become more commercially viable.

This study focused on the effect of a typical phenolic inhibitor, vanillin, on the growth and ethanol production of Starmerella bacillaris R5, as well as the effect of varying levels of glucose on its growth and fermentation performance. The results indicated that when the vanillin concentration was fixed at 3 g/L, increasing glucose concentration in the medium from 2% to 6% shorten the lag phage by 25.92%, increased the specific growth rate by 82.1%, and the ethanol conversion rate by 17.88%. Further analysis showed that increased glucose concentration resulted in an increase in the proportion of cells containing reactive oxygen species (ROS), a decrease in membrane permeability, and a reduction in intracellular H2O2 content. In addition, the activities of catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) increased by 58%, 35.5%, and 2.3 times, respectively. Intracellular glycerol content increased by 1.82 times. The activity of pyruvate kinase (PK), related to glucose metabolism, decreased by 54.5%, and the activity of hexokinase (HK) and 6-phosphate glucose dehydrogenase (6-PGDH) increased by 4.16 and 11.8 times, respectively. The content of reduced nicotinamide adenine dinucleotide phosphate (NADPH) increased by 19.4%. The gene expression levels of hexokinase (HK), 6-phosphate fructose kinase (PFK), isocitrate dehydrogenase (IDH3), 6-phosphate glucose dehydrogenase (PGD), ethanol dehydrogenase (ADH5), pyruvate decarboxylase (PDC) and glycerol dehydrogenase 1 (GCY1) were up-regulated by 4.6, 2.5, 13.9, 12.2, 17.5, 34.8, and 34.9 times, respectively. In summary, increasing glucose concentration increased the activity of intracellular antioxidant enzymes, attenuated oxidative damage, and provided more adenosine triphosphate (ATP) and reducing powder to cope with environmental stress, thereby increasing the conversion rate of ethanol. The results of this study could provide new ideas for utilizing S. bacillaris for bioethanol production.

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Synthetic microbial communities have emerged as an attractive route for chemical bioprocessing. They are argued to be superior to single strains through microbial division of labor (DOL), but the exact mechanism by which DOL confers advantages remains unclear. Here, we utilize a synthetic Saccharomyces cerevisiae consortium along with mathematical modeling to achieve tunable mixed sugar fermentation to overcome the limitations of single-strain fermentation. The consortium involves two strains with each specializing in glucose or xylose utilization for ethanol production. By controlling initial community composition, DOL allows fine tuning of fermentation dynamics and product generation. By altering inoculation delay, DOL provides additional programmability to parallelly regulate fermentation characteristics and product yield. Mathematical models capture observed experimental findings and further offer guidance for subsequent fermentation optimization. This study demonstrates the functional potential of DOL in bioprocessing and provides insight into the rational design of engineered ecosystems for various applications. Synthetic microbial communities are suitable for mixed substrates fermentation and long metabolic pathway engineering. Here, the authors combine fermentation experiments with mathematical modeling to reveal the effect of compositional and temporal changes on division of labor in cellulosic ethanol production using two yeast strains. [ABSTRACT FROM AUTHOR]

The degradation of cellulosic ethanol wastewater by peroxymonosulfate (PMS) is one of the important methods to solve the environmental problems caused by it. In order to improve the degradation efficiency of cellulosic ethanol wastewater, the design of more catalytically active and stable chalcogenide catalysts has become a problem that needs to be solved nowadays. The application of foreign cations to replace the A- or B-site to increase the oxygen vacancy of the chalcocite catalyst to improve the efficiency of chalcocite catalytic degradation of wastewater has received much attention. In this work, the perovskite material LaCuO3 was synthesized using a citric acid-sol–gel method, and the novel material La1-xSrxCuO3 was prepared by doping of Sr element at the A position. In order to prepare catalytic materials with better performance, this study carried out performance-optimized degradation experiments on the prepared materials and determined that the catalytic efficiency of La0.5Sr0.5CuO3 prepared under the conditions of the complexing agent dosage of 1:2, the gel temperature of 80 °C, and the calcination temperature of 700 °C was better than that of the catalytic materials prepared under other conditions. The prepared material has good recycling function; after four times recycling, the removal rate of pollutant COD is still more than 85%. This work provides a new synthesis method of perovskite material with good recycling function and high catalytic efficiency for the degradation technology of cellulosic ethanol wastewater. [ABSTRACT FROM AUTHOR]

Considering global economic and environmental –benefits, green renewable biofuels such as ethanol and butanol are considered as sustainable alternatives to fossil fuels. Thus, developing a co-culture strategy for ethanol and butanol production by Saccharomyces cerevisiae and Clostridium beijerinckii has emerged as a promising approach for biofuel production from lignocellulosic biomass. This study developed a co-culture of S. cerevisiae and C. beijerinckii for ethanol and butanol production from non-detoxified corn stover hydrolysate. By firstly inoculating 3 % S. cerevisiae and then 7 % C. beijerinckii with 8–10 h time intervals, the optimized co-culture process gave 24.0 g/L ABE (20.8 g/L ethanol and 2.4 g/L butanol), obtaining ABE yield and productivity of 0.421 g/g and 0.55 g/L/h. The demonstrated co-culture strategy made full use of hexose and pentose in hydrolysate and contributed to total yield and efficiency compared to conventional ethanol or ABE fermentation, indicating its great potential for developing economically feasible and sustainable bioalcohols production. • Co-culture by yeast and clostridia was developed using non-detoxified lignocellulosic hydrolysate. • Lignocellulosic sugars were made full use of for ethanol and butanol production with high yield. • Inoculating yeast first helped to metabolize dissolved oxygen and acidic inhibitors in hydrolysates. [ABSTRACT FROM AUTHOR]

The research article addresses, a novel natural cellulosic fiber namely Doum Palm Leaf Stalk Fibers (DPLSF) were extracted from Doum palm tree (Chamaerops humilis L.) are rich in cellulose, relatively inexpensive, and readily available in Algeria. The characteristic analysis on morphological, physiochemical, thermal and mechanical proprieties of the extracted raw and treated DPLSF with 20% sodium bicarbonate at various times of treatment were exanimated by optical microscope and scanning electron microscopy (SEM), X-ray diffraction method (XRD), Fourier transform infrared (FTIR) spectroscopy, thermos gravimetric analysis (TGA/DTG), differential scanning calorimetry (DSC). The SEM micrographs of the longitudinal topographic surface of the DPLSF after chemical treatment with sodium bicarbonate at various times treatment indicated that the removed the waxy layer and impurities from surface and formed a roughened surface. XRD analysis further confirmed the treatment's positive effect on the fibers, with the crystallinity index increasing from 71.43% to 81.03%. However, FTIR analysis showed minimal changes in the peak position and intensity of transmittance. The TGA/DTG results revealed a significant mass loss in treated DPLSF, while thermal stability improved from 290°C to 330°C. Additionally, we analyzed the mechanical tensile properties of the treated fibers and observed that fibers treated at 20% NaHCO3 for 24 h exhibited the highest Young's modulus 8.63 GPa. To validate the experimental findings, we compared individual DPLSF results to a numerical simulation using ABAQUS code. This study underscores the potential of DPLSF as a sustainable and eco-friendly alternative to synthetic fibers, offering immense promise for diverse applications. [ABSTRACT FROM AUTHOR]

The burgeoning cellulosic ethanol industry necessitates advancements in enzymatic saccharification, effective pretreatments for lignin removal, and the cultivation of crops more amenable to saccharification. Studies have demonstrated that natural inhibitors of lignin biosynthesis can enhance the saccharification of lignocellulose, even in tissues generated several months post‐treatment. In this study, we applied daidzin (a competitive inhibitor of coniferaldehyde dehydrogenase), piperonylic acid (a quasi‐irreversible inhibitor of cinnamate 4‐hydroxylase), and methylenedioxy cinnamic acid (a competitive inhibitor of 4‐coenzyme A ligase) to 60‐day‐old crops of two conventional Brazilian sugarcane cultivars and two energy cane clones, bred specifically for enhanced biomass production. The resultant biomasses were evaluated for lignin content and enzymatic saccharification efficiency without additional lignin‐removal pretreatments. The treatments amplified the production of fermentable sugars in both the sugarcane cultivars and energy cane clones. The most successful results softened the most recalcitrant lignocellulose to the level of the least recalcitrant of the biomasses tested. Interestingly, the softest material became even more susceptible to saccharification. [ABSTRACT FROM AUTHOR]

Saccharum is relatively new to 33° N latitude. S. spontaneum readily hybridizes with commercial sugarcane (Saccharum spp.) and lends cold tolerance and greater yield to the hybrid progeny, called energycane. Since 2007, there have been numerous new hybrid and backcross energycane genotypes developed but there is a paucity of information about them. Twenty energycane genotypes were tested in the first season of growth from cane propagules (plant cane; PC) against Ho 02-113 (a control) for two site-years in northcentral Mississippi. Grand (exponential) growth continued into October. The prevailing paradigm is that tonnage is what matters. Except for percentage cellulose, all factors tested (dry matter yield, extractable juice volume, °Brix, theoretical ethanol from fermentation, theoretical ethanol from cellulose, and total theoretical ethanol) were greater from the second site-location compared to the first. Dry matter yield (DMY) and total theoretical ethanol yield (TTEY) were moderately correlated. Over the two years of this test only Ho 14-9213 exceeded in mean DMY of Ho 02-113. Sixteen of the 19 test genotypes in this test equaled or exceeded the mean TTEY of Ho 02-113.

The economical and efficient commercial production of second-generation bioethanol requires fermentation microorganisms capable of entirely and rapidly utilizing all sugars in lignocellulosic hydrolysates. In this study, we developed a recombinant Saccharomyces cerevisiae strain, BLH510, through protoplast fusion and metabolic engineering to enhance its ability to co-ferment glucose, xylose, cellobiose, and xylooligosaccharides while tolerating various inhibitors commonly found in lignocellulosic hydrolysates. The parental strains, LF1 and BLN26, were selected for their superior glucose/xylose co-fermentation capabilities and inhibitor tolerance, respectively. The fusion strain BLH510 demonstrated efficient utilization of mixed sugars and high ethanol yield under oxygen-limited conditions. Under low inoculum conditions, strain BLH510 could completely consume all four kinds of sugars in the medium within 84 h. The fermentation produced 33.96 g/L ethanol, achieving 84.3% of the theoretical ethanol yield. Despite the challenging presence of mixed inhibitors, BLH510 successfully metabolized all four sugars above after 120 h of fermentation, producing approximately 30 g/L ethanol and reaching 83% of the theoretical yield. Also, strain BLH510 exhibited increased intracellular trehalose content, particularly under conditions with mixed inhibitors, where the intracellular trehalose reached 239.3 mg/g yeast biomass. This elevated trehalose content contributes to the enhanced stress tolerance of BLH510. The study also optimized conditions for protoplast preparation and fusion, balancing high preparation efficiency and satisfactory regeneration efficiency. The results indicate that BLH510 is a promising candidate for industrial second-generation bioethanol production from lignocellulosic biomass, offering improved performance under challenging fermentation conditions. Our work demonstrates the potential of combining protoplast fusion and metabolic engineering to develop superior S. cerevisiae strains for lignocellulosic bioethanol production. This approach can also be extended to develop robust microbial platforms for producing a wide array of lignocellulosic biomass-based biochemicals.

Cellulosic ethanol is the key technology to alleviate the pressure of energy supply and climate change. However, the ethanol production process, which is close to industrial production and has a high saccharification rate and ethanol yield, still needs to be developed. This study demonstrates the effective conversion of poplar wood waste into fuel-grade ethanol. By employing a two-step pretreatment using sodium chlorite (SC)-dilute sulfuric acid (DSA), the raw material achieved a sugar conversion rate exceeding 85% of the theoretical value. Under optimized conditions, brewing yeast co-utilizing C6/C5 enabled a yield of 35 g/L ethanol from 10% solid loading delignified poplar hydrolysate. We increased the solid loading to enhance the final ethanol concentration and optimized both the hydrolysis and fermentation stages. With 20% solid loading delignified poplar hydrolysate, the final ethanol concentration reached 60 g/L, a 71.4% increase from the 10% solid loading. Our work incorporates the pretreatment, enzymatic hydrolysis, and fermentation stages to establish a simple, crude poplar waste fuel ethanol process, expanding the range of feedstocks for second-generation fuel ethanol production.

In this work, machine learning (ML) applications in lignocellulosic bioethanol production were reviewed. First, the pretreatment-hydrolysis-fermentation route, the most commonly studied alternative, was summarized. Next, a bibliometric analysis was performed to identify the current trends in the field; it was found that ML applications in the field are not only increasing but also expanding their relative share in publications, with bioethanol seeming to be the most frequently researched topic while biochar and biogas are also receiving increased attention in recent years. Then, the implementation of ML for lignocellulosic bioethanol production via this route was reviewed in depth. It was observed that artificial neural network (ANN) is the most commonly used algorithm (appeared in almost 90% of articles), followed by response surface methodology (RSM) (in about 25% of articles) and random forest (RF) (in about 10% of articles). Bioethanol concentration is the most common output variable in the fermentation step, while fermentable sugar and glucose concentration are studied most in hydrolysis. The datasets are usually small, while the fitnesses of the models (R2) are usually high in the papers reviewed. Finally, a perspective for future studies, mostly considering improving data availability, was provided.

Ethanol, a common renewable energy resource, can reduce greenhouse gas (GHG) emissions to resolve the problem of global warming worldwide. Various feedstocks such as corn, sugarcane, maize stover, and wheat straw can be utilized for ethanol production. They determine production operations and relevant costs. Although there are monetary incentives and government policies in different countries to increase ethanal use, it is still challenging to make its sales price competitive due to the inefficient supply chain of ethanol. Unlike fossil fuels such as coal, oil, and natural gas using a well-designed supply chain in the long history of mankind, additional efforts are needed to organize and stabilize the supply chain of ethanol efficiently. The goal of this study is to investigate how simulation modeling techniques can be applied to various supply chain management issues of ethanol. Particularly, application cases of three major simulation paradigms such as discrete-event simulation, system dynamics, and agent-based simulation are investigated by conducting a scientific literature review. The findings of this study will contribute to the expansion of simulation use in the field of biofuel supply chain management. [ABSTRACT FROM AUTHOR]

The production of liquid fuels and chemicals from biomass is an essential part of establishing a bioeconomy. Numerous techno‐economic studies have been published on different pathways for processing biomass. To examine the progress made in this field, a meta‐analysis investigating three exemplary biobased products was conducted. Using recently published techno‐economic studies, the (average) unit production costs for biodiesel, cellulosic ethanol and kraft lignin were investigated. Findings in this study are based on an understanding of two phenomena: economies of scale and the learning effect. Economies of scale can be observed for each case, with kraft lignin extraction indicating the greatest cost advantages and the production of biodiesel the smallest. The investigation of potential learning effects revealed by the data yielded unexpected results: In two out of three cases, the calculated average unit production cost was observed to increase over time. These results contradict the expected influence of learning effects on calculated unit production costs as these did not decrease over time for a specific technology. A closer investigation of processing pathways and feedstocks shows that a diversification in research has occurred over the last three decades. Different driving forces of innovation related to the investigated products are also identified. [ABSTRACT FROM AUTHOR]

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Xylose is the second most abundant carbohydrate in nature, mostly present in lignocellulosic material, and representing an appealing feedstock for molecule manufacturing through biotechnological routes. However, Saccharomyces cerevisiae-a microbial cell widely used industrially for ethanol production-is unable to assimilate this sugar. Hence, in a world with raising environmental awareness, the efficient fermentation of pentoses is a crucial bottleneck to producing biofuels from renewable biomass resources. In this context, advances in the genetic mapping of S. cerevisiae have contributed to noteworthy progress in the understanding of xylose metabolism in yeast, as well as the identification of gene targets that enable the development of tailored strains for cellulosic ethanol production. Accordingly, this review focuses on the main strategies employed to understand the network of genes that are directly or indirectly related to this phenotype, and their respective contributions to xylose consumption in S. cerevisiae, especially for ethanol production. Altogether, the information in this work summarizes the most recent and relevant results from scientific investigations that endowed S. cerevisiae with an outstanding capability for commercial ethanol production from xylose. [ABSTRACT FROM AUTHOR]

Deep eutectic solvents (DESs) with a hydrophobic aromatic ring structure offer a promising pretreatment method for the selective delignification of lignocellulosic biomass, thereby enhancing enzymatic hydrolysis. Further investigation is needed to determine whether the increased presence of aromatic rings in hydrogen bond receptors leads to a more pronounced enhancement of lignin removal. In this study, six DES systems were prepared using lactic acid (LA)/acetic acid (AA)/levulinic acid (LEA) as hydrogen bond donors (HBD), along with two independent hydrogen bond acceptors (HBA) (benzyl triethyl ammonium chloride (TEBAC)/benzyl triphenyl phosphonium chloride (BPP)) to evaluate their ability to break down sugarcane bagasse (SCB). The pretreatment of the SCB (raw material) was carried out with the above DESs at 120 °C for 90 min with a solid–liquid ratio of 1:15. The results indicated that an increase in the number of aromatic rings may result in steric hindrance during DES pretreatment, potentially diminishing the efficacy of delignification. Notably, the use of the TEBAC:LA-based DES under mild operating conditions proved highly efficient in lignin removal, achieving 85.33 ± 0.52% for lignin removal and 98.67 ± 2.84% for cellulose recovery, respectively. The maximum digestibilities of glucan (56.85 ± 0.73%) and xylan (66.41 ± 3.06%) were attained after TEBAC:LA pretreatment. Furthermore, the maximum ethanol concentration and productivity attained from TEBAC:LA-based DES-pretreated SCB were 24.50 g/L and 0.68 g/(L·h), respectively. Finally, the comprehensive structural analyses of SCB, employing X-rays, FT-IR, and SEM techniques, provided valuable insights into the deconstruction process facilitated by different combinations of HBDs and HBAs within the DES pretreatment. [ABSTRACT FROM AUTHOR]

In this research, 3356 alcohol-related traffic crashes were obtained from blood-alcohol test reports in Tianjin, China. Population density, intersection density, road density, and alcohol outlet densities, including retail density, entertainment density, restaurant density, company density, hotel density, and residential density, were extracted from 2114 traffic analysis zones (TAZs). After a spatial autocorrelation test, the multiple linear regression model (MLR), geographically weighted Poisson regression model (GWPR), and semi-parametric geographically weighted Poisson regression model (SGWPR) were utilized to explore the spatial effects of the aforementioned variables on drunk-driving crash density. The result shows that the SGWPR model based on the adaptive Gaussian function had the smallest AICc value and the best-fitting accuracy. The residential density and the intersection density are global variables, and the others are local variables that have different influences in different regions. Furthermore, we found that the influence of local variables in the economic–technological development area shows significantly different characteristics compared with other districts. Thus, a comprehensive consideration of spatial heterogeneity would be able to improve the effectiveness of the programs formulated to decrease drunk driving crashes. [ABSTRACT FROM AUTHOR]

The energy crisis triggers the use of energy sources that are renewable, such as biomass made from lignocellulosic materials, to produce various chemical compounds for food ingredients and biofuel. The efficient conversion of lignocellulosic biomass into products with added value involves the activity of microorganisms, such as yeasts. For the conversion, microorganisms must be able to use various sugars in lignocellulosic biomass, including pentose sugars, especially xylose. This study aims to isolate xylose-utilizing yeasts and analyze their fermentation activity to produce xylitol and ethanol, as well as their ability to grow in liquid hydrolysate produced from pretreated lignocellulosic biomass. Nineteen yeast isolates could grow on solid and liquid media using solely xylose as a carbon source. All isolates can grow in a xylose medium with incubation at 30 °C, 37 °C, 42 °C, and 45 °C. Six isolates, namely SLI (1), SL3, SL6, SL7, R5, and OPT4B, were chosen based on their considerable growth and high xylose consumption rate in a medium with 50 g/L xylose with incubation at 30 °C for 48 h. Four isolates tested, namely SLI (1), SL6, SL7, and R5, can produce xylitol in media containing xylose carbon sources. The concentration of xylitol produced was determined using high-pressure liquid chromatography (HPLC), and the results ranged from 5.0 to 6.0 g/L. Five isolates tested, namely SLI (1), SL6, SL3, R5, and OPT4B, can produce ethanol. The ethanol content produced was determined using gas chromatography (GC), with concentrations ranging from 0.85 to 1.34 g/L. Three isolates, namely SL1(1), R5, and SL6, were able to produce xylitol and ethanol from xylose as carbon sources and were also able to grow on liquid hydrolyzate from pretreated oil palm trunk waste with the subcritical water method. The three isolates were further analyzed using the 18S rDNA sequence to identify the species and confirm their phylogenetic position. Identification based on DNA sequence analysis revealed that isolates SL1(1) and R5 were Pichia kudriavzevii, while isolate SL6 was Candida xylopsoci. The yeast strains isolated from this study could potentially be used for the bioconversion process of lignocellulosic biomass waste to produce value-added derivative products. [ABSTRACT FROM AUTHOR]

Millions of hectares of cover crops are planted in the U.S. and European Union to manage soil erosion, soil fertility, water quality, weeds, and climate change. Although only a small percentage of cover crops are harvested, the growing cover crop planting area provides a new biomass source to the biofuel industry to produce bioenergy. Oilseed crops such as rapeseed, sunflower, and soybean are commodities and have been used to produce biodiesel and sustainable aviation fuel (SAF). Other cover crops such as cereal rye, clover, and alfalfa, have been tested on small or pilot scales to produce cellulosic ethanol, biogas, syngas, bio-oil, and SAF. Given the various biofuel products and pathways, this review aimed to provide a comprehensive comparison of biofuel yield from different cover crops and an overview of the technologies that have been employed to improve biofuel yield. It was envisioned that gene-editing tools might be revolutionary to the biofuel industry, the work on cover crop supply chain will be critical for system scaleup, and high-tolerant technologies likely will be needed to handle the high compositional heterogeneity and variability of cover crop biomass for biofuel. [ABSTRACT FROM AUTHOR]

Agribusiness is the main branch of the Brazilian economy. Every year, millions of tons of agro-industrial waste are generated and improperly disposed on soil and water, generating social and environmental impacts. However, these wastes can be used as substrate for fungal growth and to produce enzymes of biotechnological interest (hydrolases, proteases, lipases). In this study, we present the production of an endoglucanase from Pycnoporus sanguineus (the first enzyme isolated from this organism) by solid-state fermentation of agro-industrial wastes. Endoglucanase was produced after 72 fermentation hours, and was isolated via ethanol fractionation and ion exchange chromatography. The isolated enzyme had an optimum temperature of 50 °C, thermostability between 30 and 60 °C, optimum pH of 5.0, stability at pH values from 5.0 to 8.0, KM of 3.18 ± 0.005 mg/mL, and kcat of 4.53 s−1. It also displayed halophilic properties. Additionally, endoglucanase was able to saccharify three kinds of agro-industrial waste in 24 h without any chemical or physical pretreatment. Rice husk, wheat bran, and sugarcane bagasse produced 273, 192, and 155 mg/mL of reducing sugars after enzymatic hydrolysis, respectively. Thus, enzyme shows to be a promising option for obtaining fermentable sugars from agro-industrial waste for the production of second-generation ethanol. [ABSTRACT FROM AUTHOR]

The degree of crystallinity in cellulose significantly affects the physical, mechanical, and chemical properties of cellulosic materials, their processing, and their final application. Measuring the crystalline structures of cellulose is a challenging task due to inadequate consistency among the variety of analytical techniques available and the lack of absolute crystalline and amorphous standards. Our article reviews the primary methods for estimating the crystallinity of cellulose, namely, X-ray diffraction (XRD), nuclear magnetic resonance (NMR), Raman and Fourier-transform infrared (FTIR) spectroscopy, sum-frequency generation vibrational spectroscopy (SFG), as well as differential scanning calorimetry (DSC), and evolving biochemical methods using cellulose binding molecules (CBMs). The techniques are compared to better interrogate not only the requirements of each method, but also their differences, synergies, and limitations. The article highlights fundamental principles to guide the general community to initiate studies of the crystallinity of cellulosic materials. [ABSTRACT FROM AUTHOR]

Clostridium thermocellum is a natively cellulolytic bacterium that is promising candidate for cellulosic biofuel production, and can produce ethanol at high yields (75–80% of theoretical) but the ethanol titers produced thus far are too low for commercial application. In several strains of C. thermocellum engineered for increased ethanol yield, ethanol titer seems to be limited by ethanol tolerance. Previous work to improve ethanol tolerance has focused on the WT organism. In this work, we focused on understanding ethanol tolerance in several engineered strains of C. thermocellum. We observed a tradeoff between ethanol tolerance and production. Adaptation for increased ethanol tolerance decreases ethanol production. Second, we observed a consistent genetic response to ethanol stress involving mutations at the AdhE locus. These mutations typically reduced NADH-linked ADH activity. About half of the ethanol tolerance phenotype could be attributed to the elimination of NADH-linked activity based on a targeted deletion of adhE. Finally, we observed that rich growth medium increases ethanol tolerance, but this effect is eliminated in an adhE deletion strain. Together, these suggest that ethanol inhibits growth and metabolism via a redox-imbalance mechanism. The improved understanding of mechanisms of ethanol tolerance described here lays a foundation for developing strains of C. thermocellum with improved ethanol production. [ABSTRACT FROM AUTHOR]

The replacement of fossil-based products with renewable alternatives is today a major research topic. Biofuels, such as second-generation ethanol, offer a promising way to overcome dependence on fossil fuels. However, second-generation biorefineries still face bottlenecks that hinder their economic sustainability. These include challenges in pretreatment (formation of inhibitors and high costs of chemicals) and hydrolysis (high enzyme costs and low solid content) and maximizing the utilization of biomass components. To achieve economic sustainability, biorefineries can adopt approaches such as integrating first and second generation (1G and 2G) technologies, using different production alternatives, or diversifying the product portfolio. This last alternative could include the simultaneous production of biomaterials, building blocks, and others from all fractions of the materials, favoring biorefinery profitability. Techno-economic assessment plays a crucial role in assessing the economic feasibility of these approaches and provides important information about the process. This article discusses how product diversification in cellulosic biorefineries enhances their economic sustainability, based on simulation techniques and techno-economic analysis, with a comprehensive and critical review of current possibilities and future trends. The information discussed can inform stakeholders about investing in 2G ethanol biorefineries, including strategies, associated risks, and profitability, allowing better planning of different options of future ventures. [ABSTRACT FROM AUTHOR]

In recent years, policy-makers and researchers have paid close attention to sustainable energy resources. Biofuel has emerged as a viable option among available alternatives in countries with excess agricultural production. India is also ramping up ethanol production. However, there is limited research available on enablers that can help boost production for enhanced blending, thereby assisting in the achievement of energy security and the transition to a low-carbon economy. Furthermore, India can capitalize on its excess agri-production for long-term energy security, increase farmer income, reduce import bills and foreign exchange outflows, encourage local business participation and accelerate its overall economic development while lowering its carbon footprints. The Decision-Making Trial and Evaluation Laboratory (DEMATEL) approach is used in this article to investigate the enablers for implementing a policy regime for increased ethanol production. The findings are important for policy-makers in India to identify areas for policy interventions, and they also lay the groundwork for future similar research on this evolving industry in the global markets. [ABSTRACT FROM AUTHOR]