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The rise of agro-industrial activities over recent decades has exponentially increased lignocellulose biomasses (LCB) production. LCB serves as a cost-effective source for fermentable sugars and other renewable chemicals. This study explores the use of microbial consortia, particularly thermophilic consortia, for LCB deconstruction. Thermophiles produce stable enzymes that retain activity under industrial conditions, presenting a promising approach for LCB conversion. This research focused on two microbial consortia (i.e., microbiomes) that were analyzed for enzyme production using a cheap medium, i.e., a mixture of spent mushroom substrate (SMS) and digestate. The secreted xylanolytic enzymes were characterized in terms of temperature and pH optima, thermal stability, and hydrolysis products from LCB-derived polysaccharides. These enzymes showed optimal activity aligning with common biorefinery conditions and outperformed a formulated enzyme mixture in thermostability tests in the digestate. Phylogenetic and genomic analyses highlighted the genetic diversity and metabolic potential of these microbiomes. Bacillus licheniformis was identified as a key species, with two distinct strains contributing to enzyme production. The presence of specific glycoside hydrolases involved in the cellulose and hemicellulose degradation underscores these consortia's capacity for efficient LCB conversion. These findings highlight the potential of thermophilic microbiomes, isolated from an industrial environment, as a robust source of robust enzymes, paving the way for more sustainable and cost-effective bioconversion processes in biofuel and biochemical production and other biotechnological applications. [ABSTRACT FROM AUTHOR]

This review explores the utilization of lignocellulosic biomass (LCB) waste in the fabrication of graphene and its applications in hydrogen storage. Several LCB wastes, such as rice straws, coconut shells, wheat straws, and sugarcane bagasse, along with the methodology used and the characteristics of the final graphene, have been discussed in detail. It was found that the coconut shells produced crumpled multilayered graphene, rice husks (RHs) provided a mix of graphene layers and amorphous carbon, wheat straw yielded few‐layered graphene, and sugarcane bagasse contributed to different graphene‐like materials. This review has also focused on the various synthesis processes, such as carbonization, hydrothermal carbonization (HTC), chemical activation, pyrolysis, chemical vapor deposition (CVD), and Hummers' method for graphene fabrication from LCB waste, along with their advantages and disadvantages, for a better understanding. Various results have been discussed exploring the use of lignocellulosic biomass‐derived graphene (LCB‐G) and its various modified forms for hydrogen storage applications. Various challenges in graphene fabrication from LCB, such as low yield, product quality, scalability, use of expensive synthesis methods, and toxic chemicals, along with some potential solutions, have been mentioned. Finally, the review concludes with insights into the future of LCB‐G and its role in hydrogen storage while identifying some gaps, such as scalability and product quality, for further research and development. [ABSTRACT FROM AUTHOR]

Lignocellulose biomass is a renewable resource with a large quantity, wide coverage, and low cost. It has gradually been developed and applied from biomass to biofuels, feedstuffs, and other value-added products. Such high-value transformation and comprehensive utilization have become important parts of “taking the path of green development and building a green production system”. However, the natural anti-degradation barrier and unique physicochemical properties of lignocellulose, as well as the rigid network of the three major components of cellulose, hemicellulose, and lignin, have been the long-term bottleneck of efficient conversion. The reasonable and effective pretreatment techniques are the key steps in the resource recovery process. This paper focuses on the analysis of basic composition and structural characteristics of lignocellulose biomass. On the basis of summarizing the advantages and disadvantages of traditional pretreatment methods such as physical, chemical, and biological methods, it emphasizes the development history, processing types, scope of application, working principle, reaction stages, technical characteristics, main parameters, and possible by-product effects of steam explosion. In addition, it involves research progress in the fiber modification, structural changes, dissolution characteristics, oligosaccharide preparation, active ingredient extraction, and ruminant feed utilization of biomass. It is also pointed out that the new trend in the post-treatment process after steam explosion assisted by microbial fermentation dominated by fungi and bacteria, as well as the exogenous addition of carbohydrase. Finally, the difficulties and challenges faced by steam explosion in future commercialization, industrialization, and large-scale production promotion are summarized. The corresponding breakthrough points and solution strategies are analyzed and proposed. The degradation effects of steam explosion technology on common by-product types of feed raw materials, as well as its reasonable application in the diet of monogastric animals, are discussed. It is aimed to provide new ideas and technical guidance for the potential development, value-added, and feed application of biomass resources using this means. [ABSTRACT FROM AUTHOR]

Lignocellulose material is the main natural resource for the pulp and paper industry, and for its application the material should have a degree of whiteness as high as possible. For this reason, different bleaching treatments were applied during time. In this paper, the photobleaching induced by solar light of a lignocellulosic biomass using NaClO was studied. The colorimetric measurements, UV spectra absorption, and FTIR spectra changes are evaluated and discussed in this paper. The changes of L*a*b parameters can be considered a proof of the reactions generated by hypochlorite radicals during solar light exposure, leading to a biomass whitening. [ABSTRACT FROM AUTHOR]

BACKGROUND: Laboratory‐scale experiments have shown that treatment with selective lignin‐degrading white‐rot fungi improves the nutritional value and ruminal degradability of lignocellulosic biomass (LCB). However, the lack of effective field‐applicable pasteurization methods has long been recognized as a major obstacle for scaling up the technique for fungal treatment of large quantities of LCB for animal feeding. In this study, wheat straw (an LCB substrate) was subjected to four field‐applicable pasteurization methods – hot‐water, formaldehyde fumigation, steam, and hydrated lime – and cultured with Pleurotus ostreatus grain spawn for 10, 20, and 30 days under solid‐state fermentation. Samples of untreated, pasteurized but non‐inoculated and fungus‐treated straws were analyzed for chemical composition, aflatoxin B1 (AFB1), and in vitro dry matter digestibility (IVDMD), in vitro total gas (IVGP), methane (CH4), and volatile fatty acid (VFA) production. RESULTS: During the 30‐day fungal treatment, steam and lime pasteurized straws had the greatest loss of lignin, resulting in marked improvements in crude protein (CP), IVDMD, IVGP, and total VFAs. Irrespective of the pasteurization method, the increase in IVDMD during fungal treatment was linearly (R2 = 0.77–0.92) related to lignin‐loss in the substrate during fungal treatment. The CH4 production of the fungus‐treated straw was not affected by the pasteurization methods. Aflatoxin B1 was within the safe level (<5 μg kg−1) in all pasteurized, fungus treated straws. CONCLUSION: Steam and lime were promising field‐applicable pasteurization techniques to produce nutritionally improved fungus‐treated wheat straw to feed ruminants. Lime pasteurization was more economical and did not require expensive energy inputs. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Lignocellulosic biomass is available in abundance as a renewable resource, but the major portion of it is often discarded as waste without utilizing its immense potential as an alternative renewable energy resource. To overcome recalcitrance of lignocellulosic biomass, various pretreatment methods are applied to it, so that the complex and rigid polymeric structure can be broken down into fractions susceptible for enzymatic hydrolysis. Effective and efficient biomass processing is the goal of pretreatment methods, but none of the explored pretreatment methods are versatile enough to fulfil the requirement of biomass processing with greater flexibility in terms of operational cost and desired output efficiency. Deployment of green solvents such as ionic liquids for the pretreatment of lignocellulosic biomass has been a topic of discussion amongst the scientific community in recent times. The presented work provides a detailed overview on the deployment of ionic liquid for the pretreatment of lignocellulosic biomass coupled with a brief discussion on other pretreatments methods. The recyclability and reusability along with other unique properties makes an ionic liquid pretreatment different from the other traditional pretreatment methods. Also, this study explores diverse critical parameters that governs the dissolution process of biomass. Hazardous properties of ionic liquids have also been explored. Future perspective and recommendations have been given for an efficient, effective, and eco-friendly deployment of ionic liquid in biomass pretreatment process. [ABSTRACT FROM AUTHOR]

The rise of agro-industrial activities over recent decades has exponentially increased lignocellulose biomasses (LCB) production. LCB serves as a cost-effective source for fermentable sugars and other renewable chemicals. This study explores the use of microbial consortia, particularly thermophilic consortia, for LCB deconstruction. Thermophiles produce stable enzymes that retain activity under industrial conditions, presenting a promising approach for LCB conversion. This research focused on two microbial consortia (i.e., microbiomes) that were analyzed for enzyme production using a cheap medium, i.e., a mixture of spent mushroom substrate (SMS) and digestate. The secreted xylanolytic enzymes were characterized in terms of temperature and pH optima, thermal stability, and hydrolysis products from LCB-derived polysaccharides. These enzymes showed optimal activity aligning with common biorefinery conditions and outperformed a formulated enzyme mixture in thermostability tests in the digestate. Phylogenetic and genomic analyses highlighted the genetic diversity and metabolic potential of these microbiomes. Bacillus licheniformis was identified as a key species, with two distinct strains contributing to enzyme production. The presence of specific glycoside hydrolases involved in the cellulose and hemicellulose degradation underscores these consortia’s capacity for efficient LCB conversion. These findings highlight the potential of thermophilic microbiomes, isolated from an industrial environment, as a robust source of robust enzymes, paving the way for more sustainable and cost-effective bioconversion processes in biofuel and biochemical production and other biotechnological applications.

5-hydroxymethylfurfural (HMF) oxidation in aqueous media using visible photocatalysis is a green and sustainable route for the valorization of lignocellulosic biomass derivatives. Several semiconductors have already been applied for this purpose; however, the use of Poly(heptazine imides), which has high crystallinity and a special cation exchange property that allows the replacement of the cation held between the layers of C3N4 structure by transition metal ions (TM), remains scarce. In this study, PHI(Na) was synthesized using a melamine/NaCl method and used as precursor to prepare metal (Fe, Co, Ni, or Cu)-doped PHI catalysts. The catalysts were tested for selective oxidation of HMF to 2,5-diformylfuran (DFF) in water and O2 atmosphere under blue LED radiation. The catalytic results revealed that the 0.1 wt% PHI(Fe) catalyst is the most efficient photocatalyst while higher Fe loading (1 and 2 wt%) favors the formation of Fe3+ clusters, which are responsible for the drop in HMF oxidation. Moreover, the 0.1 wt% PHI(Fe) photocatalyst has strong oxidative power due to its efficiency in H2O2 production, thus boosting the generation of nonselective hydroxyl radicals (●OH) via different pathways that can destroy HMF. We found that using 50 mM, the highest DFF production rate (393 μmol·h−1·g−1) was obtained in an aqueous medium under visible light radiation. [ABSTRACT FROM AUTHOR]

There is a growing trend toward the use of renewable sources to produce clean energy and mitigate the effects of climate change. Second-generation lignocellulose biomasses, such as agro-residues, comprise a potential energy source as a byproduct of agriculture. Ecuador has optimal climate conditions that allow for the cultivation of different types of crops. This makes agriculture a relevant economic activity in the country; however, the residues obtained from agriculture have not been investigated for the establishment of a bioenergy industry. This study evaluated the potential of three varieties of sugarcane bagasse, named PR 980, CC 85-92, and CB 40-59, for bioenergy production in the Ecuadorian Andes. The bagasse was quantified by means of weighing, and then evaluated via calorimetry and thermogravimetric analysis as well as proximal and elemental analysis. The results showed that these materials met the criteria for direct combustion, exhibiting both a low nitrogen content of 0.30 ± 0.12% and ash values of 6.20 ± 1.20%. Among the analyzed varieties, CB 40-69 stood out as the most suitable for power generation within the cogeneration system; this was attributed to its superior dry calorific value of 17.37 ± 1.45 MJ kg−1, greater presence of volatile materials, and negligible ash content. Variety CB 40-69 (157.91 t ha−1) reported the highest biomass and bagasse production (56.32 t ha−1). Analysis of the SCB structure concluded that the three varieties did not differ significantly in their contents of lignin, hemicellulose, and cellulose, which is essential to implementing an industrial process for bioethanol production. [ABSTRACT FROM AUTHOR]

[Display omitted] • NaOH and KOH pre-treatment enhanced solubilisation of paunch solid waste. • Cattle and sheep paunch was compared at lignocellulosic composition level. • Paunch digestion hydrolysis rate was significantly enhanced by up to 4.4 times. • Paunch digestion methane yield was improved by 60% using alkaline pre-treatment. • First-time addressing alkaline pre-treatment using [OH−] molar concentration. Paunch is comprised of the partially digested feed contained in cattle or sheep and contributes 20–50% of organic waste produced at red meat processing facilities. Anaerobic digestion has been identified as a promising technology for paunch treatment, however treatment times can be long and when combined with the moderate degradability of paunch this results in high treatment costs that need to be improved. Pre-treatment was investigated as a strategy to improve AD of paunch, alkaline treatment (NaOH or KOH) was selected due to the high lignin content. A range of alkaline loadings (1–20 g 100gTS−1) were tested with an equivalent hydroxide molar concentration of 9–250 mM [OH−]. Alkaline pre-treatment improved both the hydrolysis rate and the overall degradability of paunch solid by up to 4.4 times and 60%, respectively. The enhanced hydrolysis rate and methane yield was correlated to changes in material composition during pre-treatment. While alkaline concentration was an important factor, there were no significant improvements at alkaline concentrations above 12 g 100gTS−1 (150 mM [OH−]). [ABSTRACT FROM AUTHOR]

Abstract The concept of biorefinery has been advancing globally and organosolv pretreatment strategy has seen an upsurge in research due to its efficiency in removing the recalcitrant lignin and dissolution of cellulose. The high-performance organosolv system uses green solvents and its reusability contributes concurrently to the biorefinery sector and sustainability. The major advantage of the current system involves the continuous removal of lignin to enhance cellulose accessibility, thereby easing the later biorefinery steps, which were immensely restricted due to the recalcitrant lignin. The current system process can be further explored and enhanced via the amalgamation of new technologies, which is still a work in progress. Thus, the current review summarizes organosolv pretreatment and the range of solvents used, along with a detailed mechanistic approach that results in efficient pretreatment of LCB. The latest developments for designing high-performance pretreatment systems, their pitfalls, and advanced assessments such as Life Cycle Assessment along with Techno-Economic Assessment have also been deliberated to allow an insight into its diverse potential applicability towards a sustainable future. Graphical Abstract

The concept of biorefinery has been advancing globally and organosolv pretreatment strategy has seen an upsurge in research due to its efficiency in removing the recalcitrant lignin and dissolution of cellulose. The high-performance organosolv system uses green solvents and its reusability contributes concurrently to the biorefinery sector and sustainability. The major advantage of the current system involves the continuous removal of lignin to enhance cellulose accessibility, thereby easing the later biorefinery steps, which were immensely restricted due to the recalcitrant lignin. The current system process can be further explored and enhanced via the amalgamation of new technologies, which is still a work in progress. Thus, the current review summarizes organosolv pretreatment and the range of solvents used, along with a detailed mechanistic approach that results in efficient pretreatment of LCB. The latest developments for designing high-performance pretreatment systems, their pitfalls, and advanced assessments such as Life Cycle Assessment along with Techno-Economic Assessment have also been deliberated to allow an insight into its diverse potential applicability towards a sustainable future. [ABSTRACT FROM AUTHOR]

The complex and heterogeneous nature of the lignin macromolecule has presented a lasting barrier to its utilization. To achieve high lignin yield, the technical lignin extraction process usually severely modifies and condenses the native structure of lignin, which is a critical drawback for its utilization in conversion processes. In addition, there is no method capable of separating lignin from plant biomass with controlled structural properties. Here, we developed an N-heterocycle-based deep eutectic solvent formed between lactic acid and pyrazole (La-Py DES) with a binary hydrogen bonding functionality resulting in a high affinity toward lignin. Up to 93.7% of lignin was extracted from wheat straw biomass at varying conditions from 90 °C to 145 °C. Through careful selection of treatment conditions as well as lactic acid to pyrazole ratios, lignin with controlled levels of ether linkage content, hydroxyl group content, and average molecular weight can be generated. Under mild extraction conditions (90 °C to 120 °C), light-colored native-like lignin can be produced with up to 80% yield, whereas ether linkage-free lignin with low polydispersity can be obtained at 145 °C. Overall, this study offers a new strategy for native lignin extraction and generating lignin with controlled structural properties. [ABSTRACT FROM AUTHOR]

Lignocellulose biomass (LCB) is a plant waste material that is generated throughout the globe in massive amounts every year and may act as an alternative source of carbon for the generation of various types of value-added products, including biofuels and carboxylic acids (e.g., formic, acetic, and succinic acid). Hence its importance to the scientific community is increasing day by day. However, LCB conversion requires diverse treatment processes, including physical, chemical, and physicochemical processes, which are not economically viable and not sustainable. Hence, the microbiological systems capable of producing desired biocatalysts for generating desired products are being developed. At present, increasing population requires higher amounts of these value-added products, so enhanced efficiency of these processes are essential. As a result, the application of multi-component microbial systems, especially consortium systems, rather than monoculture systems, is prioritized for the amelioration of LCB waste conversion and formation of value-added products. The present review aims to critically analyze the different strategies used by microbial consortia to generate value-added products and discuss the future prospects of this field for the upcoming research. [ABSTRACT FROM AUTHOR]

This study deals with a preliminary investigation of biomass samples' physicochemical, structural composition, and thermal properties to aid the appropriate selection of biomass utilized for pyrolysis operation. The proximate, ultimate, structural composition and thermal analyses were conducted using seven lignocellulose biomass samples obtained in Ajase market, Ajasse Ipo, Kwara State, Nigeria, and Omu-Aran, Kwara State, Nigeria. Results showed that the average moisture contents (MC) ranged from 0.12 to 0.44%, and volatile matter (VM) ranged from 73.70 to 83.82%. Fixed carbon (FC) varied from 12.79 to 22.80%, and Ash contents varied between 01.20 to 5.52%. Similarly, the average carbon contents ranged from 45.11 to 50.00%. Hydrogen contents ranged from 5.38 to 6.15%, nitrogen contents varied between 0.20 to 1.24%, and oxygen contents from 43.79 to 48.51%. Also, sulphur contents varied between 0.01 to 0.19%, while the biomass species' average cellulose, hemicellulose, and lignin contents ranged from 28.34 to 45.80%, 25.83 to 34.01%, and 21.96 to 49.63% respectively. The high percentage of VM, C, H, HHV, ignitability index, cellulose, and hemicellulose content recorded in the biomass samples would enhance devolatilization reactivity, ignitability, and burn gases in the reactor, as well as a good production of hydrocarbons content during the pyrolysis process. Also, the low ash content would prevent harmful chemical deposits in the reactor during the pyrolysis process. It can be deduced that shea butter wood was best suited for biofuel generation, closely followed by sugarcane bagasse and palm kernel shell. At the same time, corn cobs possessed the least properties for the pyrolysis process.

The utilization of lignocellulose biomass as an alternative source of renewable energy production via green technology is becoming important, and is in line with sustainable development goal initiatives. Lignocellulolytic bacteria, such as Bacillus spp., can break down biomass by producing hydrolytic enzymes, which are crucial in the successful conversion of biomass or lignocellulosic material into renewable energy. This information gave rise to this study, where municipal solid waste sediments of a sanitary municipal solid waste landfill were sampled and screened, and lignocellulolytic bacteria were isolated and characterized. Samples were taken from four different locations at the Pulau Burung landfill site in Malaysia. Lignin and starch were used as sources of carbon to identify potential bacteria that exhibit multi-enzymatic activity. The growth rate and doubling time of bacterial isolates in lignin and starch were taken as the criteria for selection. Eleven bacterial isolates were screened for cellulase activity using iodine and Congo red dyes. The cellulase activity of these isolates ranged from 0.8 to 1.7 U/mL. We carried out 16S rRNA gene sequencing to identify the phyla of the selected bacterial isolates. Phylogenetic analysis was also conducted based on the 16S rRNA sequences of the bacterial isolates and related Bacillus species, and a tree was generated using the Neighbor-Joining method. In this study, Bacillus proteolyticus, Bacillus Sanguinis, Bacillus spizizenii, Bacillus paramycoides, Bacillus paranthracis and Neobacillus fumarioli were identified as promising bacteria capable of expressing lignocellulolytic enzymes and degrading the lignocellulosic biomass present in municipal solid waste. [ABSTRACT FROM AUTHOR]

[Display omitted] • Various lignocellulose biomasses are hydrothermally carbonized with PVC. • Insoluble lignin affected synergistic interactions, inhibiting chlorine removal. • Inorganics removal is always enhanced due to leaching and metathesis reaction. • Synergistic index on dechlorination ranged from −20.3% to 19.9%. • Synergistic index on inorganics removal ranged from 0.74% to 154%. Co-hydrothermal carbonization (co-HTC) of lignocellulose biomass (LB) and chlorinated waste can simultaneously remove organic chlorine and inorganics, however, the interaction mechanisms are unclear owing to the variety of operating conditions and complexity of biomass compositions. Pine, bamboo, corncob, corn stalk, and wheat straw were co-hydrothermally carbonized with polyvinyl chloride (PVC) at the mass ratio of 9:1 for 30 min under 260 °C to explore the fundamental interactions. The synergistic index (SI) of dechlorination efficiency ranged from −20.3 % to 19.9 %, indicating the interaction depended on the content and composition of cellulose, hemicellulose, and lignin in the LB feedstocks. Hydroxyl functional groups in cellulose and soluble lignin dehydration intermediates promoted PVC substitution. The LB fragments prevented PVC aggregation while promoted PVC fragmentation, thereby facilitating dechlorination. The polyaromatic hydrochar derived from insoluble lignin and polymeric hydrochar derived from hemicellulose, cellulose, and soluble lignin can coat the surface of molten PVC and act as significant dechlorination inhibitors. All SI of removal efficiency of inorganics (RE) were positive, ranging from 0.74 % to 154 %, with large variations for different inorganics, indicating that inorganics contents in LB influenced RE significantly. A large amount of water-insoluble/acid-soluble inorganics was removed via a metathesis reaction. Soluble inorganics were dissolved in the process water by HCl leaching. [ABSTRACT FROM AUTHOR]

One of the main strategies for sustainable human society progress is the development of efficient strategies to limit waste production and maximize renewable resource utilization. In this context, this review highlights the opportunity to transform vegetable biomass residues into valuable commercial products. Biomass conversion entails the depolymerization of lignocellulosic biomass towards biopolyols and the synthesis and characterization of the valuable products obtained by using them. The influence of the reaction parameters in both acid and basic catalysis is highlighted, respectively the influence of microwaves on the liquefaction reaction versus conventional heating. Following the depolymerization reaction, polyols are employed to produce polyurethane foams. As a special characteristic, the addition of flame-retardant properties was emphasized. Another interesting topic is the biodegradability of these products, considering the negative consequences that waste accumulation has on the environment. [ABSTRACT FROM AUTHOR]

Mushroom production in India has registered a considerable growth in the recent times. However, cultivation of shiitake mushroom, which represents a major share at a global level, is still at a primitive stage in the Indian subcontinent. The scarcity of raw materials and the cost of energy for substrate sterilization are the major hurdles for a large-scale production. The present study delves into the possibility of growing shiitake mushroom on lignocellulosic biomass (saw dust and wheat straw) processed with different heat treatments to develop a cost-effective production technology. Six different strains of shiitake mushroom, viz., DMRO-35, 51, 297, 388s, 410, 412, were used in this study. The substrates were exposed to a pasteurization temperature of 80 ± 5 °C in a bulk pasteurization chamber for three different times (H1–H3) and also to a high-pressure sterilization (H4) in an autoclave. DMRO-388s was found to be the most productive strain, irrespective of the substrate and heat treatment method used. Significant differences were observed in the biological yield depending on the type of substrate and heat treatment. Changes in the biochemical composition of the lignocellulosic residues in three different stages, viz., pre heat treatment, inoculation and primordial formation stages, were recorded. Changes in heat treatment levels and duration significantly altered the cellulose/lignin ratio of the growing substrate. High-pressure sterilization aided the rapid degradation of lignin in the substrate and increased its bioavailability, thereby facilitating the fungus achieving its potential yield. A significant correlation in the positive direction between the yield levels of the tested strains and the consumption of lignin in the growing substrate was found, suggesting the significance of pre heat treatment for the bioconversion of lignin and its subsequent utilization in the solid-state fermentation process. The substrate pre heat treatment under high-pressure sterilization was proved to be beneficial to obtain the maximum yields of shiitake mushroom. [ABSTRACT FROM AUTHOR]

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5-hydroxymethylfurfural (HMF) oxidation in aqueous media using visible photocatalysis is a green and sustainable route for the valorization of lignocellulosic biomass derivatives. Several semiconductors have already been applied for this purpose; however, the use of Poly(heptazine imides), which has high crystallinity and a special cation exchange property that allows the replacement of the cation held between the layers of C3N4 structure by transition metal ions (TM), remains scarce. In this study, PHI(Na) was synthesized using a melamine/NaCl method and used as precursor to prepare metal (Fe, Co, Ni, or Cu)-doped PHI catalysts. The catalysts were tested for selective oxidation of HMF to 2,5-diformylfuran (DFF) in water and O2 atmosphere under blue LED radiation. The catalytic results revealed that the 0.1 wt% PHI(Fe) catalyst is the most efficient photocatalyst while higher Fe loading (1 and 2 wt%) favors the formation of Fe3+ clusters, which are responsible for the drop in HMF oxidation. Moreover, the 0.1 wt% PHI(Fe) photocatalyst has strong oxidative power due to its efficiency in H2O2 production, thus boosting the generation of nonselective hydroxyl radicals (●OH) via different pathways that can destroy HMF. We found that using 50 mM, the highest DFF production rate (393 μmol·h−1·g−1) was obtained in an aqueous medium under visible light radiation.

There is a growing trend toward the use of renewable sources to produce clean energy and mitigate the effects of climate change. Second-generation lignocellulose biomasses, such as agro-residues, comprise a potential energy source as a byproduct of agriculture. Ecuador has optimal climate conditions that allow for the cultivation of different types of crops. This makes agriculture a relevant economic activity in the country; however, the residues obtained from agriculture have not been investigated for the establishment of a bioenergy industry. This study evaluated the potential of three varieties of sugarcane bagasse, named PR 980, CC 85-92, and CB 40-59, for bioenergy production in the Ecuadorian Andes. The bagasse was quantified by means of weighing, and then evaluated via calorimetry and thermogravimetric analysis as well as proximal and elemental analysis. The results showed that these materials met the criteria for direct combustion, exhibiting both a low nitrogen content of 0.30 ± 0.12% and ash values of 6.20 ± 1.20%. Among the analyzed varieties, CB 40-69 stood out as the most suitable for power generation within the cogeneration system; this was attributed to its superior dry calorific value of 17.37 ± 1.45 MJ kg−1, greater presence of volatile materials, and negligible ash content. Variety CB 40-69 (157.91 t ha−1) reported the highest biomass and bagasse production (56.32 t ha−1). Analysis of the SCB structure concluded that the three varieties did not differ significantly in their contents of lignin, hemicellulose, and cellulose, which is essential to implementing an industrial process for bioethanol production.

The progress of clean alternative energy sources is of very essential owing to the increase in an energy crisis and the escalating problems of climatic change. In this regard, bioenergy generation from carbohydrate-rich Lignocellulose biomass (LCB) is a promising technique, owing to its benefits such as ease of availability, decrease in harmful emissions, eco-friendly, energy efficiency and sustainability. The key constituents present in LCB are cellulose, hemicellulose, and lignin. This biological conversion of LCB faces difficulties due to the recalcitrance of lignin. Thus, the delignification of LCB is essential for the removal of complex lignin compounds. The primary technologies employed for the conversion of LCB biomass to bioenergy and pretreatment technologies involved in removing the lignin barrier have been extensively discussed in the present review. Different microorganisms and enzymes used for the delignification and detoxification process have also been studied for the scaling up of industrial bioenergy production from LCB.

Extremophiles provide a one-of-a-kind source of enzymes with properties that allow them to endure the rigorous industrial conversion of lignocellulose biomass into fermentable sugars. However, the fact that most of these organisms fail to grow under typical culture conditions limits the accessibility to these enzymes. In this study, we employed a functional metagenomics approach to identify carbohydrate-degrading enzymes from Ethiopian soda lakes, which are extreme environments harboring a high microbial diversity. Out of 21,000 clones screened for the five carbohydrate hydrolyzing enzymes, 408 clones were found positive. Cellulase and amylase, gave high hit ratio of 1:75 and 1:280, respectively. A total of 378 genes involved in the degradation of complex carbohydrates were identified by combining highthroughput sequencing of 22 selected clones and bioinformatics analysis using a customized workflow. Around 41% of the annotated genes belonged to the Glycoside Hydrolases (GH). Multiple GHs were identified, indicating the potential to discover novel CAZymes useful for the enzymatic degradation of lignocellulose biomass from the Ethiopian soda Lakes. More than 73% of the annotated GH genes were linked to bacterial origins, with Halomonas as the most likely source. Biochemical characterization of the three enzymes from the selected clones (amylase, cellulase, and pectinase) showed that they are active in elevated temperatures, high pH, and high salt concentrations. These properties strongly indicate that the evaluated enzymes have the potential to be used for applications in various industrial processes, particularly in biorefinery for lignocellulose biomass conversion. [ABSTRACT FROM AUTHOR]

This study deals with a preliminary investigation of biomass samples' physicochemical, structural composition, and thermal properties to aid the appropriate selection of biomass utilized for pyrolysis operation. The proximate, ultimate, structural composition and thermal analyses were conducted using seven lignocellulose biomass samples obtained in Ajase market, Ajasse Ipo, Kwara State, Nigeria, and Omu-Aran, Kwara State, Nigeria. Results showed that the average moisture contents (MC) ranged from 0.12 to 0.44%, and volatile matter (VM) ranged from 73.70 to 83.82%. Fixed carbon (FC) varied from 12.79 to 22.80%, and Ash contents varied between 01.20 to 5.52%. Similarly, the average carbon contents ranged from 45.11 to 50.00%. Hydrogen contents ranged from 5.38 to 6.15%, nitrogen contents varied between 0.20 to 1.24%, and oxygen contents from 43.79 to 48.51%. Also, sulphur contents varied between 0.01 to 0.19%, while the biomass species' average cellulose, hemicellulose, and lignin contents ranged from 28.34 to 45.80%, 25.83 to 34.01%, and 21.96 to 49.63% respectively. The high percentage of VM, C, H, HHV, ignitability index, cellulose, and hemicellulose content recorded in the biomass samples would enhance devolatilization reactivity, ignitability, and burn gases in the reactor, as well as a good production of hydrocarbons content during the pyrolysis process. Also, the low ash content would prevent harmful chemical deposits in the reactor during the pyrolysis process. It can be deduced that shea butter wood was best suited for biofuel generation, closely followed by sugarcane bagasse and palm kernel shell. At the same time, corn cobs possessed the least properties for the pyrolysis process. [ABSTRACT FROM AUTHOR]

Objectives: The research aims to analyze the catabolic strength of different hydrolytic enzymes in assessing the biological conversion potential of lignocellulose parts of agricultural biomass wastes into functional edible sugars and biofuels. Materials and Methods: The enzymes' hydrolytic properties—versatile peroxidase, manganese peroxidase, and lignin peroxidase were used to identify their complexing strength with the lignin substrate, whereas endoglucanase cel12A, acidocaldarius cellulase, and Melanocarpus albomyces endoglucanase were tested on the cellulose gel substrate. Because the biodegradation properties are heavily influenced by the "enzyme-substrate complexing energy level," proper molecular optimization and energy minimization of the enzymes and substrates were carried out, as well as the identification of the enzyme's active sites prior to complexing. comprehensive molecular dynamic simulation was run to study their—alpha carbon, root-mean-square deviation (Å), molecular surface area (Å2), root-mean-square fluctuation (Å), radius of gyration (nm), hydrogen bonds with hydrophobic interactions, and solvent accessible surface area (Å2) values for 50 ns. The simulated data mining was conducted using advanced programming algorithms to establish the final enzyme-substrate complexing strength in binding and catalysis. Results: Among the lignin-degrading enzymes, versatile peroxidase shows promising catalytic activity with the best docking pose and significant values in all the dynamic simulation parameters. Similarly, Melanocarpus albomyces endoglucanase shows the best activity in all aspects of molecular docking and dynamics among the cellulose-degrading enzymes. Conclusion: The lignin content of biomass wastes can be degraded into cellulose and hemicellulose using lignin-degrading enzymes. The cellulose can be further degraded into glucose and xylose sugars following the cellulose-degrading enzyme activity. These sugars can be further degraded into biofuel through anaerobic fermentation. Systematic bioconversion of the lignocellulosic components can ensure sustainable biomass management, creating an alternative food and energy source for human beings to face the challenges of global hunger where the enzymes can pave the way. [J Adv Vet Anim Res 2022; 9(1.000): 19-32]

The production of bio-oil is a complex process influenced by various parameters. Optimizing these parameters can significantly enhance bio-oil yield, thus improving process efficiency. This study aims to develop a predictive model for bio-oil yield using the Gradient Boosting Regression (GBR) technique. It also seeks to identify the key factors affecting bio-oil yield and determine the optimal conditions for maximizing production. The GBR model was constructed using data collected from the literature. The model's performance was evaluated based on its determination coefficients for training and testing datasets. Optimization studies were conducted to identify the best conditions for bio-oil production. The GBR model demonstrated high precision, with determination coefficients of 0.983 and 0.913 for the training and testing datasets, respectively, indicating its effectiveness in predicting bio-oil yield. The optimal conditions for maximizing bio-oil yield were identified as 20 min of pyrolysis time, a temperature of 771 °C, and 524W of microwave power. The two-way PDP analysis provided valuable insights into the interactive effects of temperature with other factors, enhancing the understanding of the dynamics of the bio-oil production process. This study not only identifies the most impactful variables for bio-oil yield but also offers critical guidance for optimizing the production process. [ABSTRACT FROM AUTHOR]

Using renewable energy is a solution to combat environmental problems; in this context, hydrothermal carbonization is an excellent method for converting biomass into solid fuels. However, this process is energy-intensive. Systems utilizing parabolic trough solar collectors proposed in the literature present some limitations and challenges. Therefore, to overcome this issue, a novel conception combining photovoltaic solar panels and a batch reactor with a heating collar has been proposed. It was experimentally investigated and subjected to energy and exergy analyses. The experimental results showed that subcritical conditions (220 °C temperature and 40 bar pressure) were achieved. The chemical exergy of the biomass increased from 19.89 MJ/kg to 29.2 MJ/kg for the hydrochar. Due to dehydration and decarboxylation, the O/C and H/C atomic ratios decreased over time, and the hydrochar properties approximated lignite. The solar panel system achieved average energy and exergy efficiencies of 14 % and 15 %, respectively, with high thermal exergy destruction of 825.94 kWh under higher wind speeds and cell temperatures, resulting in a total entropy of 1.4 kW/K. The system's Improvement Potential ranged from 15 kW to 23 kW. The results demonstrate the feasibility of this innovative system to achieve the necessary conditions for HTC in an environmentally friendly manner. [ABSTRACT FROM AUTHOR]

The utilization of ionic liquids (ILs) in the conversion of lignocellulose to levulinic acid (LA) is a significant pathway in the field of bio-refinery. In this study, a series of sulfonic-based ILs with elongated alkyl chains were synthesized using density functional theory. These ILs were then utilized for the conversion of straw into LA in a single reaction vessel. The yield of LA was compared between a single solvent (water) and a biphasic system comprising water and methyl isobutyl ketone (MIBK). Among the investigated ILs, [C 3 SO 3 HEim]Cl exhibited a higher yield of LA, reaching up to 11.3 wt% in the aqueous phase and 17.8 wt% in the MIBK-water biphasic system. Furthermore, [C 3 SO 3 HEim]Cl displayed a high catalytic efficiency (90.4%) and a yield of LA (16.3 wt%) after 5 cycles. These findings suggest that the elongation of alkyl side chains in ILs enhances the solubility of cellulose and increases the yield of LA. The MIBK-water biphasic system promotes the rehydration of hydroxymethylfurfural (HMF) and reduces the residence time of LA in the aqueous phase, thereby optimizing its yield. This innovative approach involving ILs and the MIBK-water biphasic system presents a novel perspective for the production of LA from biomass. [Display omitted] • Levulinic acid was directly produced from straw biomass using ionic liquid. • The experimental design adopts the combination of molecular simulation and experiments. • The yield of levulinic acid was improved by using the Water-MIBK two-phase system. • The prepared ionic liquid can be reused multiple times in the reaction system. [ABSTRACT FROM AUTHOR]

• Characterized temperature of pyrolysis was studied by conversion curvature • Activation energy of lignin was underestimated in three parallel reaction model • Three parallel reaction model is inaccurate to estimate characterized temperatures • Kinetic study using parallel finite number first-order reaction model is reliable In this work, the pyrolysis behaviors and kinetics of two bamboo (Bambusa texlitis) wastes were investigated via thermogravimetric analysis. The weight loss behaviors of pyrolysis were studied by curvature of the conversion (α) curves. The curvature of α can depict the characteristic temperatures of pseudo component (hemicellulose, cellulose and lignin) pyrolysis. Model-free model was applied to estimate the apparent activation energies of the pure components for comparison with other kinetic models. Three parallel reaction (TPR) and parallel finite number first-order reaction (FNFOR) models were used for kinetic studies. The first-order TPR model underestimates the apparent activation energies of pseudo components. The n th-order TPR model underestimates the apparent activation energy of lignin and obtains characteristic temperatures that are inconsistent with those of pure lignin. The parallel FNFOR model is more reliable for simulating the kinetics of lignocellulosic biomass pyrolysis. The apparent activation energies of pseudo components depend on the variety of lignocellulosic biomass. [Display omitted] [ABSTRACT FROM AUTHOR]

Fundamental study on material properties of lignocellulose fiber is important to understand the performance of composite materials. In this study, we explored several material properties of untreated, commercial and wood ash alkali retted fiber obtained from relatively less studied and traditionally important wild plant species Sterculia villosa (local name Murgilo or Mudilo) and Bauhinia vahlii fibers (local name Bharlo). Water sorption kinetics in all fiber types was measured at ambient temperature. Fickian model then was used to fit experimental sorption kinetic data and information on diffusion coefficients at early and late stages of sorption, average diffusion coefficient, sorption coefficient, and water permeability were obtained. The average diffusion coefficient (D) for untreated, wood ash alkali and commercial alkali treated Sterculia was found to be 10.6 × 10-13 m2/sec, 3.08 × 10-12 m2/sec, and 2.35 × 10-12 m2/sec; respectively. The corresponding values for Bauhinia fiber were found to be 6.8 × 10-13 m2/sec, 3.80 × 10-12 m2/sec, and 3.46 × 10-12 m2/sec; respectively. The equilibrium water sorption in the alkali treated fiber was significantly reduced due to removal of cementing materials and also increase of crystallinity. Significant decrease in mechanical strength of fiber in sorbed state was found. These findings will be useful to understand stability of fiber and potential end products such as paper sheets and reinforced composite materials exposed under different moisture conditions.

Extremophiles provide a one-of-a-kind source of enzymes with properties that allow them to endure the rigorous industrial conversion of lignocellulose biomass into fermentable sugars. However, the fact that most of these organisms fail to grow under typical culture conditions limits the accessibility to these enzymes. In this study, we employed a functional metagenomics approach to identify carbohydrate-degrading enzymes from Ethiopian soda lakes, which are extreme environments harboring a high microbial diversity. Out of 21,000 clones screened for the five carbohydrate hydrolyzing enzymes, 408 clones were found positive. Cellulase and amylase, gave high hit ratio of 1:75 and 1:280, respectively. A total of 378 genes involved in the degradation of complex carbohydrates were identified by combining high-throughput sequencing of 22 selected clones and bioinformatics analysis using a customized workflow. Around 41% of the annotated genes belonged to the Glycoside Hydrolases (GH). Multiple GHs were identified, indicating the potential to discover novel CAZymes useful for the enzymatic degradation of lignocellulose biomass from the Ethiopian soda Lakes. More than 73% of the annotated GH genes were linked to bacterial origins, with Halomonas as the most likely source. Biochemical characterization of the three enzymes from the selected clones (amylase, cellulase, and pectinase) showed that they are active in elevated temperatures, high pH, and high salt concentrations. These properties strongly indicate that the evaluated enzymes have the potential to be used for applications in various industrial processes, particularly in biorefinery for lignocellulose biomass conversion.

This review covers the operating conditions for extracting top value-added chemicals, such as levulinic acid, lactic acid, succinic acid, vanillic acid, 3-hydroxypropionic acid, xylitol, 2,5-furandicarboxylic acid, 5-hydroxymethyl furfural, chitosan, 2,3-butanediol, and xylo-oligosaccharides, from common lignocellulosic biomass. Operating principles of novel extraction methods, beyond pretreatments, such as Soxhlet extraction, ultrasound-assisted extraction, and enzymatic extraction, are also presented and reviewed. Post extraction, high-value biochemicals need to be isolated, which is achieved through a combination of one or more isolation and purification steps. The operating principles, as well as a review of isolation methods, such as membrane filtration and liquid–liquid extraction and purification using preparative chromatography, are also discussed. [ABSTRACT FROM AUTHOR]

Although high-solid enzymatic hydrolysis has emerged as an efficient strategy of sugar production from lignocellulosic materials, this process requires several steps to increase its efficiency. Current strategies include treatments to remove noncellulosic macromolecules. Here, dilute alkaline extraction was controlled to remove loosely bound xylan from sugarcane bagasse, and 14.7% (w/w) was recovered by ethanol precipitation. To the supernatant, sodium sulfite (5% w/w) was added to pretreat the residual sugarcane bagasse with alkaline sulfite ethanol (ASE). The sequential process allowed the removal of 85% of lignin, producing a carbohydrate-enriched solid. Incubation of ASE-pretreated bagasse with xylanase released up to 43% of the xylan as oligomers. Subsequent enzymatic saccharification was performed at initial solid loadings, 5, 10, and 15%. The conversion of ASE-pretreated bagasse yielded 84.4% glucan hydrolysis or 75 g/L glucose at 15% solids after 48 h, while samples with reduced xylan contents had lower water retention, and achieved relevant glucan hydrolysis yield (73%) and glucose titer (87 g/L). Enzymatic saccharification at high solid loading was dependent on xylan removal, and control of excess residual xylan may play an important role in fine-tuning product formation in high-solid enzymatic hydrolysis of the glucan fraction. [ABSTRACT FROM AUTHOR]

A thermophilic Geobacillus bacterial strain, WSUCF1 contains different carbohydrate-active enzymes (CAZymes) capable of hydrolyzing hemicellulose in lignocellulosic biomass. We used proteomic, genomic, and bioinformatic tools, and genomic data to analyze the relative abundance of cellulolytic, hemicellulolytic, and lignin modifying enzymes present in the secretomes. Results showed that CAZyme profiles of secretomes varied based on the substrate type and complexity, composition, and pretreatment conditions. The enzyme activity of secretomes also changed depending on the substrate used. The secretomes were used in combination with commercial and purified enzymes to carry out saccharification of ammonia fiber expansion (AFEX)-pretreated corn stover and extractive ammonia (EA)-pretreated corn stover. When WSUCF1 bacterial secretome produced at different conditions was combined with a small percentage of commercial enzymes, we observed efficient saccharification of EA-CS, and the results were comparable to using a commercial enzyme cocktail (87% glucan and 70% xylan conversion). It also opens the possibility of producing CAZymes in a biorefinery using inexpensive substrates, such as AFEX-pretreated corn stover and Avicel, and eliminates expensive enzyme processing steps that are used in enzyme manufacturing. Implementing in-house enzyme production is expected to significantly reduce the cost of enzymes and biofuel processing cost. [ABSTRACT FROM AUTHOR]

The upstream of bioenergy industry has suffered from unreliable operations of granular biomass feedstocks in handling equipment. Computational modeling, including continuum-mechanics models and discrete-particle models, offers insightful understandings and predictive capabilities on the flow of milled biomass and can assist equipment design and optimization. This paper presents a benchmark study on the fidelity of the continuum and discrete modeling approaches for predicting granular biomass flow. We first introduce the constitutive law of the continuum-mechanics model and the contact law of the coarse-grained discrete-particle model, with model parameters calibrated against laboratory characterization tests of the milled loblolly pine. Three classical granular material flow systems (i.e., a lab-scale rotating drum, a pilot-scale hopper, and a full-scale inclined plane) are then simulated using the two models with the same initial and boundary conditions as the physical experiments. The close agreement of the numerical predictions with the experimental measurements on the hopper mass flow rate, the hopper critical outlet width, the material stopping thickness on the inclined plane, and the dynamic angle of repose, clearly indicates that the two methods can capture the critical flow behavior of granular biomass. The qualitative comparison shows that the continuum-mechanics model outperforms in parameterization of materials and wall friction, and large-scale systems, while the discrete-particle model is more preferred for discontinuous flow systems at smaller scales. Industry stakeholders can use these findings as guidance for choosing appropriate numerical tools to model biomass material flow in part of the optimization of material handling equipment in biorefineries.

A thermophilic Geobacillus bacterial strain, WSUCF1 contains different carbohydrate-active enzymes (CAZymes) capable of hydrolyzing hemicellulose in lignocellulosic biomass. We used proteomic, genomic, and bioinformatic tools, and genomic data to analyze the relative abundance of cellulolytic, hemicellulolytic, and lignin modifying enzymes present in the secretomes. Results showed that CAZyme profiles of secretomes varied based on the substrate type and complexity, composition, and pretreatment conditions. The enzyme activity of secretomes also changed depending on the substrate used. The secretomes were used in combination with commercial and purified enzymes to carry out saccharification of ammonia fiber expansion (AFEX)-pretreated corn stover and extractive ammonia (EA)-pretreated corn stover. When WSUCF1 bacterial secretome produced at different conditions was combined with a small percentage of commercial enzymes, we observed efficient saccharification of EA-CS, and the results were comparable to using a commercial enzyme cocktail (87% glucan and 70% xylan conversion). It also opens the possibility of producing CAZymes in a biorefinery using inexpensive substrates, such as AFEX-pretreated corn stover and Avicel, and eliminates expensive enzyme processing steps that are used in enzyme manufacturing. Implementing in-house enzyme production is expected to significantly reduce the cost of enzymes and biofuel processing cost.

The utilization of lignocellulose biomass as an alternative source of renewable energy production via green technology is becoming important, and is in line with sustainable development goal initiatives. Lignocellulolytic bacteria, such as Bacillus spp., can break down biomass by producing hydrolytic enzymes, which are crucial in the successful conversion of biomass or lignocellulosic material into renewable energy. This information gave rise to this study, where municipal solid waste sediments of a sanitary municipal solid waste landfill were sampled and screened, and lignocellulolytic bacteria were isolated and characterized. Samples were taken from four different locations at the Pulau Burung landfill site in Malaysia. Lignin and starch were used as sources of carbon to identify potential bacteria that exhibit multi-enzymatic activity. The growth rate and doubling time of bacterial isolates in lignin and starch were taken as the criteria for selection. Eleven bacterial isolates were screened for cellulase activity using iodine and Congo red dyes. The cellulase activity of these isolates ranged from 0.8 to 1.7 U/mL. We carried out 16S rRNA gene sequencing to identify the phyla of the selected bacterial isolates. Phylogenetic analysis was also conducted based on the 16S rRNA sequences of the bacterial isolates and related Bacillus species, and a tree was generated using the Neighbor-Joining method. In this study, Bacillus proteolyticus, Bacillus Sanguinis, Bacillus spizizenii, Bacillus paramycoides, Bacillus paranthracis and Neobacillus fumarioli were identified as promising bacteria capable of expressing lignocellulolytic enzymes and degrading the lignocellulosic biomass present in municipal solid waste.