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Homogeneous metal salt catalysts play a pivotal role in industrial production of 5‐hydroxymethylfurfural (HMF). Herein, we first proposed the anion effect on steerable production of HMF using metal salts with different anions as catalyst in a biphasic system of tetrahydrofuran (THF)/NaCl aqueous solution (NaCl aq). Notably, the anions affected the catalytic activity of the metal salts, leading to an order of magnitude difference in the HMF yields, i.e. AlBr3 (74.0 mol %)>AlCl3 (60.8 mol %)>Al2(SO4)3 (35.2 mol %)>Al(NO3)3 (14.9 mol %). The anion effect on steerable production of HMF could be attributed to the proximity effect and electron tension. Anions form close‐range interactions with glucose molecules by proximity effect to promote electron transfer, facilitating the isomerization of glucose to fructose. Besides, anions induce a reduction of the electron cloud density of glucose carbon atoms, generating electron tension that rapidly transforms glucose from the ground state to the transition state, thereby increasing the HMF yield. Based on the revelation of anions effect and evaluation of techno‐economic process, we expect to provides theoretical guidance for high‐throughput screening of metal salt catalysts in industrial biorefinery. [ABSTRACT FROM AUTHOR]

Within the circular bioeconomy the production of optically pure LA from 2nd generation feedstocks would be ideal but it is very challenging. In this paper genetically engineered Escherichia coli strains were created to resolve racemic LA solutions synthesised and produced from the fermentation of organic waste or ensiled grass. Refining LA racemic mixtures into either a D- or L-LA was achieved by cells being able to consume one LA isomer as a sole carbon and energy source while not being able to consume the other. A D-LA refining strain JSP0005 was grown on fermented source-sorted organic household waste and different grass silage leachates, which are 2nd generation feedstocks containing up to 33 g/L lactic acid racemate. In all growth experiments, L-LA was completely removed leaving D-LA as the only LA stereoisomer, i.e. resulting in optically pure D-LA, which also increased by as much as 248.6 % from its starting concentration, corresponding to 38 g/L. The strains resulting from this study are a promising first step towards a microbial based LA biorefining process. [Display omitted] • Genetically engineered Escherichia coli strains yield optically pure lactic acid from racemic mixtures. • These strains could allow racemic lactic acid solutions to be obtained from cheap and abundant 2nd generation feedstocks. • D‐lactic acid was produced while all L-lactic acid was removed from grass silage leachates and fermented organic wastes. [ABSTRACT FROM AUTHOR]

Background: Biorefinery using microorganisms to produce biofuels and value-added biochemicals derived from renewable biomass offers a promising alternative to meet our sustainable energy and environmental goals. The ethanologenic strain Zymomonas mobilis is considered as an excellent chassis for constructing microbial cell factories for diverse biochemicals due to its outstanding industrial characteristics in ethanol production, high specific productivity, and Generally Recognized as Safe (GRAS) status. Nonetheless, the restricted substrate range constrains its application. Results: The truncated ice nucleation protein InaK from Pseudomonas syringae was used as an autotransporter passenger, and α-amylase was fused to the C- terminal of InaK to equip the ethanol-producing bacterium with the capability to ferment renewable biomass. Western blot and flow cytometry analysis confirmed that the amylase was situated on the outer membrane. Whole-cell activity assays demonstrated that the amylase maintained its activity on the cell surface. The recombinant Z. mobilis facilitated the hydrolysis of starch into oligosaccharides and enabled the streamlining of simultaneous saccharification and fermentation (SSF) processes. In a 5% starch medium under SSF, recombinant strains containing Peno reached a maximum titer of 13.61 ± 0.12 g/L within 48 h. This represents an increase of 111.0% compared to the control strain's titer of titer of 6.45 ± 0.25 g/L. Conclusions: By fusing the truncated ice nucleation protein InaK with α-amylase, we achieved efficient expression and surface display of the enzyme on Z. mobilis. This fusion protein exhibited remarkable enzymatic activity. Its presence enabled a cost-effective bioproduction process using starch as the sole carbon source, and it significantly reduced the required cycle time for SSF. This study not only provides an excellent Z. mobilis chassis for sustainable bioproduction from starch but also highlights the potential of Z. mobilis to function as an effective cellular factory for producing high-value products from renewable biomass. [ABSTRACT FROM AUTHOR]

Aloe vera (AV) leaf rind, a potent second-generation lignocellulosic biomass, was employed for fermentative co-production of lactic acid (LA) and acetone-butanol-ethanol (ABE) using Bacillus coagulans MTCC 492 and Clostridium acetobutylicum MTCC 11274, respectively. A systematic sequential biomass treatment using deep eutectic solvents (DESs) (Glyc, choline chloride:glycerol, and Reln, choline chloride:urea), mild sulfuric acid (1%, v/v) (MSA), and cellulase was adopted for lignin fractionation, pentose (C5), and hexose (C6) hydrolysates preparation. It has been observed that adoption of DES pretreatment tends to reduce the fermentative inhibitors (predominantly lignin derived) by 2.36-fold after MSA saccharification as compared to the conventional acid (2%, v/v) (CA) pretreatment. Additionally, DES exerted a significant structural disintegration of biomass as evident from SEM, FTIR, NMR, and XRD that favored subsequent saccharification. Maximum delignification of 76.87% (w/w) was obtained when biomass was treated with Glyc-MSA that in turn yielded 70.71 g/L of total sugar. Bacillus coagulans MTCC 492, an efficient LA producer through pentose sugar utilization, resulted in 35.87 g of LA/L of the hydrolysate. Subsequently, the cellulose-rich residual biomass (after Glyc-MSA) when hydrolyzed enzymatically using cellulase yielded a hydrolysate containing 34.44 g/L of total sugar. Clostridium acetobutylicum MTCC 11274 was employed for fermentation of this C6 sugar-rich hydrolysate that resulted in 4.83 g/L of total ABE. Through this study, a multi-product development strategy was formulated for systematic utilization of AV leaf rind cell wall components (lignin, cellulose, and hemicellulose) towards its segregated bio-based utilization. [ABSTRACT FROM AUTHOR]

Steam explosion (STEX) of woody biomass is an efficient pretreatment method in the production of water-resistant wood pellets. The STEX process also generates an aqueous condensate stream containing dissolved organic compounds, with furfural as the most abundant and valuable component. An industrial-scale recovery process for furfural and other organic by-products is therefore in the process of being developed and built. One challenge in the process has turned out to be the formation of solid particulate matter that can clog filters in the process unit. We have analyzed both the solid deposits and the fluids present at different points in the process unit to try to identify the origin of the particles using spectroscopic and chromatographic analysis, elemental analysis, and scanning electron microscopy. The aqueous fluids deriving from condensed steam contain furfural and other small organic molecules, with a separate low-density organic layer occurring at some points. This layer largely consists of wood extractives, typically terpenoids. In addition, a heavy organic phase comprising mostly furfural was found at one sampling point. The particles comprise a black, largely insoluble material with a H/C ratio of 0.88 and an O/C ratio of 0.26 and a very low ash content. IR spectra show a low content of C–H functional groups, and chromatographic analysis supports an interpretation that the particles are dominantly furfural-sourced humin-like polymers with adsorbed or co-polymerized terpenoids. Particle formation has been reproduced in a laboratory setting with conditions similar to those in the full-scale process. [ABSTRACT FROM AUTHOR]

Sugarcane wax is a co‐product with strong potential. It contains several bioactive components that can be used for pharmaceutical and cosmetic purposes. It is also considered a substitute for leading vegetable waxes in the international market. The extraction and refining technologies that have been reported in Cuba do not always manage to deliver a wax that meets the quality demanded by the market. This problem can be solved with the development of innovative technologies that allow increasing yields, higher quality, and the reduction of costs. The main objective of this work was to achieve a validated model of the Cuban sugarcane wax‐refining process using the SuperPro Designer simulator, and to evaluate the alternatives in order to reduce consumption rates and increase stability in the final product quality, as customers demand. The model successfully replicated 39 out of 44 variables used for process validation, with values falling within the historical range of the process. Deviations from historical values were less than 4 percentage points. Among the proposed modifications, the second of the two alternatives proposed resulted in lower consumption rates and more consistent quality of refined wax. [ABSTRACT FROM AUTHOR]

Biochar, a carbon‐rich material derived from organic biomass under low‐O2 conditions, has gained importance due to its role in mitigating climate change by sequestering carbon. It can be used as an alternative energy source and has applications in nutrient cycling, improving soil properties, and removing heavy metals and organic pollutants, thus contributing to sustainable agriculture and environmental remediation. In the face of alarming climate change, rising energy demand, and increasing pollution, the integration of biochar production into biorefineries is an important strategy to promote a sustainable and circular economy. Adopting a holistic approach to biomass utilization by developing strategies to maximize biochar production along with the production of other value‐added products while improving its quality can increase biorefineries' overall sustainability and efficiency. Fine‐tuning the biorefinery process from feedstock selection to co‐production, optimizing pyrolysis conditions, and integrating it with other technologies can help to achieve this goal while generating zero waste and diversified revenues. With the biochar market growing exponentially, further research into the long‐term impact of biochar on carbon sequestration and its application in the environment is the next step. [ABSTRACT FROM AUTHOR]

Efficient pretreatment methods are crucial for the generation of fermentable sugars from the renewable lignocellulose. In this study, γ-valerolactone (GVL), a biomass-derived green solvent, was used to fractionate corn stover (CS). The impact of different additives on the enzymatic hydrolysis and pretreatment of CS within the GVL/water system was carefully investigated. The results demonstrate that the use of H 2 SO 4 -assisted GVL/H 2 O (80:20, w/w) pretreatment at mild conditions successfully facilitates the depolymerization of CS, thereby improving the cellulase accessibility. Furthermore, by increasing the GVL pretreatment temperature to 160 °C with 100 mM H 2 SO 4 addition, the pretreated CS led to nearly 100 % of hydrolysis yield at 2 % (w/v) solid load. Finally, the thermogravimetric analysis (TGA) was performed to evaluate the thermal decomposition characteristics of untreated CS and enzymatic residues based on the H 2 SO 4 -assisted GVL/H 2 O pretreatment. The results indicate that the enzymatic residues had two depolymerization stages from 200 °C to 500 °C with a final residual mass of 22.73 %, which was higher than that of untreated CS (20.56 %). Overall, this study provides an efficient lignocellulose pretreatment for fermentable sugars production and valorization of enzymatic residues. [Display omitted] • Using H 2 SO 4 as γ-valerolactone (GVL) pretreatment additive enhanced xylan removal. • Glucose yield of GVL-pretreated corn stover (CS) was 3–5 folds higher than raw CS. • Sugars production reached 32.4 g/100 g CS by 50 mM H 2 SO 4 -assisted GVL pretreatment. • Enzymatic residues had two decomposition stages in 200–500 °C by thermal analysis. [ABSTRACT FROM AUTHOR]

Enzymatic hydrolysis is an efficient processing method for valorizing chicken rest raw material by generating new food- or feed ingredients. This paper characterizes two types of chicken rest raw material: viscera and a mixture of bones, skin and remaining meat, and evaluates how industrially relevant hydrolysis process designs affect overall yield of all products, including hydrolysate, sediment, lipid, and emulsion. Eleven hydrolyses were performed using viscera and bone materials, endogenous and commercial enzymes, pre-treatments, variations in water addition and hydrolysis times. Compared to bone materials, viscera had higher proteolytic activity, more readily water-soluble components, and lower effect of adding commercial enzymes on product yields. The process of heating the raw material to hydrolysis temperature greatly impacted product yields, representing about 50 % of the overall hydrolysate production from viscera during hydrolysis. Pre-inactivation of endogenous enzymes reduced initial, but not final, hydrolysate yields. Adding commercial enzymes to pre-inactivated viscera had no effect on yields compared to not adding enzymes. Reducing water addition lowered initial hydrolysate yield from bone material. Lipid yield reflected lipid content in the raw material, and thermal pre-separation of lipids did not increase the total lipid recovery. In general, hydrolysis of viscera generated more emulsion than the bone material. [Display omitted] • Composition and proteolytic activity vary between chicken rest raw material fractions. • Hydrolysate represents 10–25 % of total dry yield of hydrolysis products. • Heating raw material before hydrolysis contributes to the overall hydrolysate yield. • Industrially relevant process design affect product yields. [ABSTRACT FROM AUTHOR]

Chemical characterization is a crucial step and decision tool before any application of fruit crop residues. This study aims to evaluate the applicability of traditional chemical characterization methods for banana pseudostem, guava seed, and orange bagasse. An analysis of extractives removal time and sugar solubilization during this process was performed. The residues were evaluated based on the cellulose, hemicellulose, lignin, extractives, and ash contents, in addition to the holocellulose and α-cellulose fractions, followed by FTIR spectroscopy. Acid-soluble lignin was evaluated by UV–visible spectrophotometry with different extinction coefficients and wavelengths. The results showed that extractives' removal for 4 h was sufficient for all materials, and a varied composition was observed among the biomasses. The guava seed had the highest lignin content, 41.66%, banana pseudostem had 33.97% cellulose, and orange bagasse had a high extractive content, 60.78%. The mass balance for all biomasses was above 92%, which suggests the applicability of such chemical characterization methods for fruit residues. A significant influence of different parameters in the determination of soluble lignin was observed. Thus, the present study serves as a basis for future research on the use and application of fruit residues, since there are no specific and complete studies on its characterization; including the evaluation of a greater number of plant varieties to obtain more representative results. [ABSTRACT FROM AUTHOR]

From harvesting to consumption of the faba bean (Vicia faba), different plant residues such as stems, leaves, pods, and seed husks remain as by-products. The harvest residues constitute about 50% (w/w) of the whole aboveground biomass, while the empty pods and the seed husks account for 11% and 6% (w/w) on average, respectively. Due to the environmental and dietary benefits, the global production of faba beans is most likely to increase in the future. Concomitantly, the amounts of by-products will rise as well. So far, mainly the harvest residues have been widely studied, whereas the pods and husks have received less consideration. Therefore, the aim of this review was to provide an overview of the composition of the faba bean plant residues and to illustrate their potential of being used as feedstock in food, feed, or even non-food applications. This literature survey clearly reveals that all the residual materials of faba beans contain valuable compounds and might be suitable for a multitude of different applications. The residual material should thus not be disposed of but further valorized in order to exploit the full potential of the biomass. [ABSTRACT FROM AUTHOR]

Polyhydroxyalkanoates (PHA) compose a family of biodegradable and biocompatible polyesters, and are a potential alternative to the use of petrochemical plastics. Poly(3-hydroxybutyrate-co-4-hydroxybutyrate) [P(3HB-co-4HB)] is an extensively studied copolymer member of the PHA family due to its medical applications. Usually, 4HB monomer incorporation depends on the supply of structurally related carbon sources, such as 4-hydroxybutyric acid, ɣ-butyrolactone (GBL), and 1,4-butanediol, although it can occur in some bacteria when supplying unrelated carbon sources, such as glucose. This review is focused on the bacterial cell factories and on the economic aspects of P(3HB-co-4HB) production, discussing strategies to broadly enable its biotechnological production on an industrial scale. Articles discussing the genetic engineering and cultivation conditions of major promising bacterial platforms to enhance P(3HB-co-4HB) production (Cupriavidus necator, Escherichia coli, Burkholderia sacchari, Halomonas bluephagenesis, and others) are reviewed, describing and comparing the advantages and disadvantages of each one. Economic aspects of large-scale P(3HB-co-4HB) manufacturing in the context of a biorefinery are analyzed, highlighting the main bottlenecks of the bioprocess. Improvement of bacterial conversion rate of GBL to 4HB and the use of cheaper substrates for 4HB incorporation to the copolymer, through the development of novel pathways and newly isolated strains, should be the main targets for future studies. [ABSTRACT FROM AUTHOR]

The current industry is based on materials derived from petroleum; however, due to the depletion of fossil fuels, it has been necessary to look for more sustainable alternatives. For that reason, different methods for the production of high-value-added molecules from carbohydrates have been developed. The focus of this review is to introduce the reader to the main catalytic routes for the production of platform molecules of great importance, such as 5-hydroxymethylfurfural and 2,5-furandicarboxylic acid, while exploring other related products. It emphasizes the use of agro-food wastes as starting material and gives an overview of pretreatment methods for lignocellulosic biomass, as this is still a challenge in the current research. This review also opens a new perspective to refocus the research towards the development of separation and purification methods as part of the integrated process, as this is a key point for future scalability. [ABSTRACT FROM AUTHOR]

The efficient fractionation and recovery of monosaccharides (xylose and glucose) from lignocellulosic biomass facilitates subsequent sugar-based derivative production. This study introduces a one-pot γ-valerolactone/ CuCl2 biphasic pretreatment system (100-mmol·L-1 CuCl2, 180 °C, 60 min) capable of achieving removal rates of 92.25% and 90.64% for xylan and lignin, respectively, while retaining 83.88% of cellulose. Compared to other metal chlorides (NaCl, LiCl, FeCl3, and AlCl3), the γ-valerolactone/CuCl2 system recovered 121.2 mg·(g eucalyptus)-1 of xylose and 55.96 mg·(g eucalyptus)-1 of glucose during the pretreatment stage and 339.2 mg·(g eucalyptus)-1 of glucose during the enzymatic hydrolysis stage (90.78% of glucose yield), achieving a total monosaccharide recovery of 86.31%. In addition, the recovery of γ-valerolactone was 79.33%, exhibiting minimal changes relative to the pretreatment performance. The method proposed in this study allows a high total monosaccharides recovery and a circular economy-oriented pretreatment approach, offering a viable pathway for biorefinery. [ABSTRACT FROM AUTHOR]

This work presents a comprehensive Social Life Cycle Assessment (S-LCA) and Social Cost-Benefit Analysis (S-CBA) conducted as part of a research project, studying biofuel production for the maritime and aviation sectors, from various types of non-food waste biomasses. The inclusion of social considerations complements and expands on the environmental and economic ones. The importance of social group criteria was determined through expert questionnaires, leading to the identification of social impacts groups and social criteria from stakeholders across participating countries. The results successfully identified and quantified social impacts, and align with those reported in similar cases in relevant literature. Social Cost-Benefits, monetarizing social factors, demonstrated several social benefits, including reduction in Greenhouse Gas Emissions. However, it also highlighted social costs, such as Economic Costs associated with the initial investment. The study revealed critical social hotspots within the impact categories, making significant strides in understanding the social impacts of biofuel production, providing valuable insights for decision-makers, and contributing to the broader goal of sustainable and socially responsible biofuel production. [ABSTRACT FROM AUTHOR]

Lignins, abundant aromatic biopolymers and one of the major components of lignocellulosic biomass, remain the most underutilized renewable bioresources of aromatics and hydrocarbons on the Earth. Numerous physical and chemical processes have been developed for lignin valorization; however, they generally suffer from environmentally unfriendly, harsh conditions and lack reaction specificity. On the other hand, milder methods involving biocatalysts exist but are impeded by many limitations, such as cofactor regeneration, deleterious enzyme–lignin interactions, and low stability. In this work, we attempt to eliminate the constrains encountered in enzyme‐based lignin valorization processes through the development of a novel electrochemically assisted bioprocess. This “all‐in‐one” biocathode incorporates a hybrid electrocatalytic interface combining a hydrogen peroxide‐generating passive air‐breathing gas diffusion electrode with an immobilized hydrogen peroxide‐consuming lignin peroxidase on a single surface and catalyzing the depolymerization of lignins. The ligninolytic potential of this bioelectrochemical device is demonstrated using both lignin models (veratryl alcohol and veratrylglycerol β‐guaiacyl ether) and a technical lignin at room temperature in aqueous media with the reaction efficiency of 14.9% per hour. [ABSTRACT FROM AUTHOR]

This study focuses on three different regions of moso bamboo (Phyllostachys edulis): an inner layer (IB), middle layer (MB), and outer layer (OB), to comprehensively characterize the structural features, chemical composition (ash, extractives and lignin contents), and the lignin monomeric composition as determined by analytical pyrolysis. The results show that bamboo presents a gradient structure. From the IB to OB, the vascular bundle density and fiber sheath ratio increase, the porosity decreases (from 45.92% to 18.14%), and the vascular bundle diameter–chord ratio increases (from 0.85 to 1.48). In terms of chemical composition, the ash, extractives, and acid-soluble lignin content gradually decrease from IB to OB. The holocellulose content follows the trend: MB (66.3%) > OB (65.9%) > IB (62.8%), while the acid-insoluble lignin content exhibits the opposite trend: IB (22.6%) > OB (17.8%) > MB (17.7%). Pyrolysis products reveal the diversity of carbohydrates and lignin derivatives, with a lignin monomeric composition rich in syringyl and guaiacyl units and lower amounts of H-units: the IB has an H:G:S relation of 18:26:55, while 15:27:58 is the ratio for the MB and 15:40:45 for the OB; S/G ratio values were, respectively, 1.22, 1.46, and 0.99. A comprehensive analysis highlights significant gradient variations in the structure and chemistry of bamboo, providing robust support for the classification and refinement methods of bamboo residues for potential applications. [ABSTRACT FROM AUTHOR]

The purple Cameroon grass crop (P. purpureum cv. Morado) presents significant potential as a source of raw materials and renewable energy; it has rapid growth, high yield, and low fertilizer demand. During the conversion of lignocellulosic biomass, hemicellulose and cellulose can first be hydrolyzed into five and six-carbon sugars, and then the sugars are converted into furfural and levulinic acid (LA) respectively. In this work, the furfural and levunilic acid production was evaluated in a two-stage catalytic process with a tin catalyst supported on a sulfonated activated carbon. In the first stage, a furfural yield of 23.28% at 170 °C for 3 h. In the second stage, the effect of process temperature and time on LA production's yield and energy demand was evaluated; LA yield of 28.17% was obtained with an energy demand of 0.12 kWh/gLA at 180.47 °C for 1.78 h. These results demonstrate the possibility of obtaining furfural from Cameroon grass. [ABSTRACT FROM AUTHOR]

The optimization of automatic solvent extraction (ASE) for obtaining grapefruit (Citrus paradisi) peel extract was conducted by Box-Behnken design under statistical experimental design approach (response surface method-RSM). The optimization is based on the D-limonene concentration since it is the major volatile compound of the grapefruit essential oil. The optimum conditions were attained with almost 7.5 g fresh grapefruit peel, and ~11 min immersion time and ~10 min washing time by application of ASE. The maximum yield was 4.91 mg D-limonene per gram fresh grapefruit peel. The reliability of the study was satisfactory (the difference between the experimental and calculated values<2%). Depending on ANOVA findings of RSM, the second power effect of mass was the most significant, followed by the second power effects of immersion time and washing time, and the linear effect of immersion time (p<0.0001). On the other hand, ~96% of the total volatile composition belong to the D-limonene depending on gas chromatography-mass spectrometry (GC-MS) measurements. Additionally, myrcene, decanal, and β-ocimene were also determined as the main flavor components in grapefruit peel extract. Moreover, the related componenens were also characterized by using nuclear magnetic resonance (1H- and 13C-NMR) techniques as well as Fourier transform infrared (FTIR) spectroscopy technology. [ABSTRACT FROM AUTHOR]

Organic compounds bearing one or more carbocycles in their molecular structure have a discernible presence in all major classes of organic products of industrial significance. However, sourcing carbocyclic compounds from exhaustible, anthropogenic carbon (e. g., petroleum) raises serious concerns about sustainability in the chemical industries. This review discusses recent advances in the renewable synthesis of carbocyclic compounds from biomass components following catalytic pathways. The mechanistic insights, process optimizations, green metrics, and alternative synthetic strategies of carbocyclic compounds have been detailed. Moreover, the renewable syntheses of carbocycles have been assessed against their existing synthetic routes from petroleum for better perspectives on their sustainability and technological preparedness. This work will assist the researchers in acquiring updated information on the sustainable synthesis of carbocyclic compounds from various biomass components, comprehending the research gaps, and developing superior synthetic processes for their commercial production. [ABSTRACT FROM AUTHOR]

The global spread of invasive plants is an important environmental problem and a real threat to biological diversity, with significant impacts on agriculture, forestry, and human and animal health. Invasive plant eradication produces large amounts of plant biomass, which should be safely utilized. The study reviews possibilities for using biomass of invasive plant species in the bioeconomy to safely convert them to items of value. Invasive plant biomass can be used as fuel or for energy production applying either biochemical or thermochemical processing technologies. The biomass of invasive plants also can be used for energy production or isolation of biologically active components. Invasive plants contain many groups of substances providing their defense potential against predators; these substances participate in metabolic regulation processes and others. Amongst the substances of interest for bioeconomy are lipids, polyphenols, alkaloids, carbohydrates, plant fibers, and essential oils. In the development of invasive plant biomass utilization strategies, the bio-based value pyramid and the waste hierarchy should be considered. Scientific sound strategies of invasive plant management will limit their spread and provide economic benefits via their eradication. [ABSTRACT FROM AUTHOR]

Microalgae are photosynthetic microorganisms that have the capacity to synthesize a diverse range of biomolecules depending on their phylogenetic classification. Microalgae hold promise as sustainable and renewable energy resources; however, their full potential remains untapped due to the costliness and time-intensive nature of downstream processing. The objective of this study is to overcome these challenges by utilizing a single processing unit for the extraction of three major biomolecule classes namely, lipids, proteins, and carbohydrates. These biomolecules of marine Chlorella sp. NITT 02 were recovered in a single extraction process using the triphasic system. The parameters defining the triphasic system were optimized for the maximum recovery of biomolecules using Response Surface Methodology (RSM) coupled Genetic Algorithm (GA) optimization. The simultaneous complete recovery of lipids with 86.46 % of total fatty acids, 97 % protein recovery and 97.1 % carbohydrate recovery were obtained with i) 2.5:1 of t-butanol:culture volume, ii) 70 % t-butanol, iii) 32.9 % ammonium sulfate, and iv) 55 min sonication time. All three extracted biomolecule classes were characterized using FTIR, GC-MS, UV-Visible spectrophotometry, and XRD. From the current investigation, the recovery efficiency of the triphasic system is higher than the conventional sequential extraction of biomolecules and the time taken for extraction is 1.25 h with energy consumption of 0.7833 kWh. Hence, the adoption of this biorefinery approach is suitable for making microalgae commercially viable for producing valuable products from the biomolecules. [ABSTRACT FROM AUTHOR]

Lignin, the second most abundant renewable carbon source on earth, holds significant potential for producing biobased specialty chemicals. However, its complex, highly branched structure, consisting of phenylpropanoic units and strong carbon-carbon and ether bonds, makes it highly resistant to depolymerisation. This recalcitrancy highlights the need to search for robust lignin-degrading microorganisms with potential for use as industrial strains. Bioprospecting for microorganisms from lignin-rich niches is an attractive approach among others. Here, we explored the ligninolytic potential of bacteria isolated from a lignin-rich underground coalmine, the Morupule Coal Mine, in Botswana. Using a culture-dependent approach, we screened for the presence of bacteria that could grow on 2.5% kraft lignin-supplemented media and identified them using 16 S rRNA sequencing. The potential ligninolytic isolates were evaluated for their ability to tolerate industry-associated stressors. We report the isolation of twelve isolates with ligninolytic abilities. Of these, 25% (3) isolates exhibited varying robust ligninolytic ability and tolerance to various industrial stressors. The molecular identification revealed that the isolates belonged to the Enterobacter genus. Two of three isolates had a 16 S rRNA sequence lower than the identity threshold indicating potentially novel species pending further taxonomic review. ATR-FTIR analysis revealed the ligninolytic properties of the isolates by demonstrating structural alterations in lignin, indicating potential KL degradation, while Py-GC/MS identified the resulting biochemicals. These isolates produced chemicals of diverse functional groups and monomers as revealed by both methods. The use of coalmine-associated ligninolytic bacteria in biorefineries has potential. [ABSTRACT FROM AUTHOR]

A biorefinery process was developed to isolate phycobiliproteins, sulfated polysaccharides, and phenolic compounds from Palmaria palmata. The extraction process was carried out in three stages using ultrasound-assisted extraction (UAE) and pressurized liquid extraction (PLE) integrated with different natural deep eutectic solvents (NaDESs). In general, PLE provided higher phycobiliprotein contents than UAE in the first step of the process. In fact, the hydrolysis product of the PLE-NaDES extracts achieved a higher antioxidant capacity than that of the UAE-NaDES extracts. Particularly, glycerol:glucose (2:1) with 50% water in combination with PLE was the most suitable NaDES to recover the highest phycobiliprotein, protein, and sulfated polysaccharide contents from Palmaria palmata in the first and second steps of the biorefinery process. Finally, a PLE-NaDES using choline chloride:glycerol (1:2) with 60% water as the NaDES was employed for the recovery of antioxidant and neuroprotective phenolic compounds from the residue of the second step, obtaining a higher total phenolic content than employing PLE with ethanol/water (70:30, v/v) as the extraction solvent. Moreover, a forced stability study revealed that the NaDESs provided a protective effect compared to the water extracts against the degradation of phycobiliproteins, preserving their color over time. This study contributes to the recovery of high-value components from an undervalued biomarine source through a sustainable biorefinery process. [ABSTRACT FROM AUTHOR]

Thailand is a prominent global producer of mangoes, providing a wide range of mango cultivars and dealing with the challenge of managing biomass. Thus, biorefining mango peel to extract valuable components has the potential to reduce organic waste and create a new revenue source for the mango processing sector. This study aims to examine the physiology, physiochemical, and chemical characteristics in peel of nine Thai mango cultivars, along with the relationship between their characteristics. The Thai mango cultivars Mahachanok, Chok anan, and Rad exhibited a yellow appearance, while the other six cultivars appeared yellow-green. However, the firmness of the fruit was directly correlated with the firmness of the pulp. A proximate composition study revealed that the predominant constituent of mango peel was carbohydrates, comprising up to 75% of its composition. This was followed by fibre, which accounted for up to 13%. The Nga mango had the highest levels of total phenolic content (220 mgGAE/g) and total flavonoid content (5.5 mgCE/g). The primary phenolic acids identified in Thai mango peel were epicatechin, caffeic acid, catechin, and gallic acid. The Mahachanok cultivar exhibited the highest antioxidant activity, as determined by the ABTS and DPPH assays, with values of 85.67% and 85.78%, respectively. This study demonstrated the connections between the physiochemical characteristics of mangoes and their chemical compositions in different cultivars, indicating the possibility of choosing particular cultivars for extracting targeted bioactive compounds. The multivariate analyses revealed that there was no correlation between the physiochemical and chemical profiles of mangoes. This study highlights the significance of mango peel as a valuable by-product that has significant environmental and economic ramifications for the mango processing industry. [ABSTRACT FROM AUTHOR]

Potatoes (Solanum tuberosum L.) are starchy tuberous crops that represent the world's fourth most important crop. According to the "Food and Agricultural Organisation of the United Nations," 376 million metric tonnes of potatoes were produced globally in 2021. It is anticipated that around 8000 kilotons of potato peel waste might be generated in 2030, with related greenhouse gas emissions of 5 million tonnes of CO2 equivalent. Waste generated throughout the food supply chain, from potato farms to forks, contributes considerably to global warming. Apart from animal feed, technical processes in the potato processing industry generate waste organic residues with high amounts of bioactive compounds and carbohydrates, and thus extraction and bioconversion processes can produce high-value products. These include the isolation of functional ingredients for the formulation of nutraceuticals and pharma products, bioenergy-related products, enzymes, and fertilizers for the market, hence contributing to a more responsible production and consumption and, overall, circular economy. This review focuses on studies involving potato waste from industries such as pulp, processed water, peels, and mash showing the great prospects of the by-products from this crop for value-added supply chains and the reduction of undesired environmental effects. This work attempts to adhere upon several Sustainable Development Goals, specifically goals 7, 12, and 13, while also contributing to long-term growth targets and reducing negative environmental consequences produced by the food sector. [ABSTRACT FROM AUTHOR]

Lately, pyrolysis has attracted significant attention due to its substantial potential for bio-oil production, with the ability to serve as a renewable energy source and/or facilitate the production of valuable chemical compounds. The chemical compounds generated and their amounts are completely influenced by the traits and chemical makeup of the initial biomass. In this work, the catalytic fast pyrolysis of Eucalyptus urograndis canopy was carried out using a pyrolyzer coupled to gas chromatography/mass spectrometry (Py-GC/MS) at different temperatures and in the presence and absence of catalysts. Elemental composition analysis was employed to characterize the chemical composition of the biomass. The results showed a biomass with a carbon percentage of 50.20%, oxygen of 43.21%, and hydrogen of 6.34%, as well as a lower calorific power of 17.51 MJ/kg. The Py-GC/MS analyses revealed the presence of several noteworthy compounds, including acetic acid (C2H4O2) and, in smaller quantities, hydrogen (H2), furfural (C5H4O2), and levoglucosan (C6H10O5). The technical-economic evaluation revealed that the production of acetic acid, furfural, hydrogen, and levoglucosan commands a high market price. Additionally, a single production cycle is anticipated to yield a favorable technical-economic balance, generating approximately USD 466.10 /ton of processed biomass. This outcome is achieved through the process of catalytic fast pyrolysis, where CuO has been identified as the most suitable catalyst. [ABSTRACT FROM AUTHOR]

In the olive oil industry, a pit fraction is collected from olive pomace and split into a clean pit fraction and a residual olive skin-rich fraction, which does not an industrial application. Therefore, in this work, microwave-assisted extraction (MAE) was applied to obtain high-value triterpene acids (maslinic acid and oleanolic acid) from this biomass using the renewable solvent ethanol. The response surface methodology was used to gain a deeper understanding of how the solvent (ethanol–water, 50–100% v/v), time (4–30 min), and temperature (50–120 °C) affect the extraction performance, as well as the energy required for the process. The effect of milling was also studied and the solid-to-liquid ratio was also evaluated, and overall, a good compromise was found at 10% (w/v) using the raw sample (unmilled biomass). The optimised conditions were applied to residual olive skin sourced from various industries, yielding up to 5.1 g/100 g and 2.2 g/100 g dry biomass for maslinic acid and oleanolic acid, respectively. In conclusion, the residual olive skin is a promising natural source of these triterpene acids, which can be extracted using MAE, releasing extracted solids rich in polymeric carbohydrates and lignin that can be valorised under a holistic biorefinery process. [ABSTRACT FROM AUTHOR]

• A microwave-assisted protocol towards biofuel precursor furfural (FF) was implemented. • Namely almond hull (AH), olive stone (OS), and wine-derived by-products were evaluated. • Mild conditions (150 °C, 10–20 min) and green strategies (AlCl 3 ·6H 2 O) were applied. • Noted molar yield (38–42 %) and selectivity (50–60 %) were achieved from AH and OS. • Sustainable waste management and biorefinery approaches were assessed. This work outlines the first microwave (MW)-assisted protocol for the production of biofuel precursor furfural (FF) from the raw agricultural waste almond hull (AH), olive stone (OS), and the winemaking-derived grape stalk (GS), grape marc (GM) and exhausted grape marc (EGM) through a one-pot synthesis process. To enhance the overall yield, a catalytic process was firstly developed from xylose, major constituent of hemicellulose present in lignocellulosic biomass. This method afforded FF with 100 % selectivity, yielding over 85 % in isolated product when using H 2 SO 4 , as opposed to a 37 % yield with AlCl 3 ·6H 2 O, at 150 °C in only 10 min. For both catalysts, the developed methodology was further validated, proving adaptable and efficient in producing the targeted FF from the aforementioned lignocellulosic raw materials. More specifically, the employment of AlCl 3 ·6H 2 O resulted in the highest selectivity (up to 89 % from GM) and FF yield (42 % and 39 % molar from OS and AH, respectively), maintaining notable selectivity for the latter (61 and 48 % from AH and OS). At this regard, and considering the environmental factor of sustainability, it is important to point out the role of AlCl 3 ·6H 2 O in contrast to H 2 SO 4 , thus mitigating detrimental substances. This study provides an important management of agricultural waste through sustainable practises for the development of potential bio-based chemicals, aligning with Green Chemistry and process intensification principles. [ABSTRACT FROM AUTHOR]

Lignocellulosic agricultural wastes are a potential feedstock for the synthesis of fuels and chemicals due to their low environmental cost, environmental friendliness, sustainability, and abundance. Therefore, corn byproducts are regarded as a valuable bioresource with multiple applications. In this study, platform chemicals, including levulinic acid (LA), formic acid (FA), and furfural (FF), were synthesized from corn husk by hydrothermal conversion using an acidic catalyst and a statistical Box-Behnken method. When selecting catalysts with MSA, H3PO4, H2SO4, HCl, and HNO3, the highest LA yield was obtained with methanesulfonic acid (MSA). At 170 °C, 12.5% biomass, 0.75 M MSA, and 40 min, the statistical optimization of corn husk conversion produced a yield of 18.0wt% LA based on biomass weight (57.75% based on carbohydrate content). Concurrently, an FA yield of 9.23wt% was achieved. At 170 °C, 5% biomass, 0.20 M MSA, and 15 min; however, a yield of 11.4wt% FF based on biomass weight (36.57% based on carbohydrate content) was obtained. LA and FA productions with combined severity did not fit the nonlinear sigmoidal model well. Nonetheless, the production of FF well-fitted the sigmoidal model with a high regression value. In corn waste biorefineries, the utilization of corn husk as bioresources and MSA as the catalyst for the synthesis of levulinic acid is well-understood. [ABSTRACT FROM AUTHOR]

This study deals with the solid waste management in tea processing industries by thermochemical conversion of the raw or industrial tea waste (ITW) for bioenergy generation and value addition. The elemental carbon (C) in ITW was 43.35%. Moreover, ITW exhibited gross calorific value (GCV) of 43.35% and 19.48 MJ/kg, which was comparable to firewood species. ITW was subjected to pyrolysis and industrial tea waste biochar (ITWBC) and industrial tea waste bio-oil (ITWB) were obtained as the main products. The pyrolysis increased the elemental C content and GCV in ITWBC up to 80.01 wt% and 24.00 MJ kg−1, respectively. Besides, alkane, alcohol, phenol, nitro, and aromatic compounds were obtained during spectroscopic analysis of ITWBC. The fixed carbon (FC) content increased from 22.50 to 74% after the conversion of ITW to ITWBC. The H/C and O/C ratios (in weight) decreased after the thermochemical conversion of ITW to ITWBC and ITWB. ITWB is comprised of 66.21% of C; the major components were phenolic (84.6%). Moreover, aromatics, esters, ethers, ketones, alcohols, furans, and aliphatic components were also identified during spectroscopic analysis of the ITWB. The spectroscopic analyses suggest effective thermochemical conversion of ITW with the involvement of chemical processes such as polymerization, dehydration, decarboxylation, aromatization, intermolecular condensations, and rearrangements. The study highlights the possibility of waste management in tea industries via integrated biorefinery approach, besides further validating the potential of ITW for energy/fuel production and value-added product development under the realm of "Waste to Wealth" technology. [ABSTRACT FROM AUTHOR]

This study aimed to identify the optimal biomass substrate from natural waste materials for Amynthas arenulus earthworm cultivation and examine its impact on growth and survival factors. Earthworms were raised in a cement pond, with their diet consisting of thirteen formulations derived from sources including cow dung, organic fertilizer, vegetable waste, and chopped banana plant trunk. The earthworm bedding was controlled with pH values of 8.0 and 6–8% of the moisture content. Thirteen formula trials were conducted on earthworm cultivation for 30 days. The results found that F8 which contained cow dung + organic fertilizer + vegetable scrap was the best substrate for A. arenulus earthworm cultivation. Survival and growth rates were presented at 93.33% and 127.67%, respectively. An increase in earthworm weight was significantly found at 425.55 mg/worm/day. It was found that the reproductive capacity of four juvenile earthworms was 0.3, following their discovery after a period of 30 days. This study reveals that substrate F8 is the optimal choice for earthworm cultivation, leading to increased productivity and promoting ecological sustainability through circular production between earthworms and soil. Moreover, F8 enhances the earthworms' ability to convert agricultural waste and serves as a fundamental basis for soil ecological remediation systems and sustainable utilization of agricultural waste. These findings hold significant implications for the utilization of F8 in earthworm cultivation and these obtained earthworms could be used in functional food and medical applications. [ABSTRACT FROM AUTHOR]

Despite advances in biofuel production and biomass processing technologies, biorefineries still experience commercialization issues. When costs exceed revenues, their long-term economic sustainability is threatened. Although integrated biorefineries have significant global potential due to process integration and product co-generation, it is crucial that they generate a positive net return, thereby incentivizing their continual operation. Nonetheless, research and development into new system designs and process integration are required to address current biorefinery inefficiencies. The integration of Bitcoin mining into biorefineries represents an innovative approach to diversify revenue streams and potentially offset costs, ensuring the economic viability and commercial success of biorefineries. When using bio-H2, a total of 3904 sats/kg fuel can be obtained as opposed to 537 sats/kg fuel when using syngas. Bitcoin, whether produced onsite or not, is an accretive asset that can offset the sales price of other produced biochemicals and biomaterials, thereby making biorefineries more competitive at offering their products. Collaborations with policy makers and industry stakeholders will be essential to address regulatory challenges and develop supportive frameworks for widespread implementation. Over time, the integration of Bitcoin mining in biorefineries could transform the financial dynamics of the bio-based products market, making them more affordable and accessible whilst pushing towards sustainable development and energy transition. [ABSTRACT FROM AUTHOR]

Converting lignin into aromatic chemicals is a promising strategy for the high‐value utilization of lignocellulosic feedstock. However, the inherent heterogeneity of lignin poses a significant obstacle to achieving efficient conversion and optimal product yields within bio‐refinery systems. Herein, we employed a one‐step fractionation method to enhance lignin homogeneity and utilized the THF/DMSO‐EtONa (tetrahydrofuran/dimethyl sulfoxide‐sodium ethoxide) system to depolymerize the fractionated lignin. Three protic and three aprotic solvents were used for fractionation. The impact of the solvent properties on the structure and the depolymerization efficiency of the fractionated lignin was investigated. Methanol‐fractionated lignin generated the benzoic acid compounds with a yield of 30 wt%, 50 % higher than that of the unfractionated lignin. The polarities (δP), hydrogen bonding abilities (δH), and viscosities (η) of selected protic solvents showed strong linear correlation with molecular weight (Mw), polymer dispersity index (PDI), and syringyl/guaiacyl ratio (S/G ratio) of the fractionated lignin, as well as the total yield of benzoic acid compounds derived from the β‐O‐4 bond cleavage. This study elucidates the relationship between solvent properties and lignin structure and proposes a promising approach for refining lignin to enhance utilization efficiency, thereby presenting a potential strategy for value‐added application of complex lignin polymers. [ABSTRACT FROM AUTHOR]

Second- and third-generation biorefineries enable the sustainable management of biomasses within the framework of circular economy principles. This approach aims to minimize waste biomass while generating high-value molecules and bio-energy, such as biogas. Biogas production is achieved via anaerobic digestion, a process where microorganisms metabolize organic compounds in the absence of oxygen to primarily produce CO2 and CH4. The efficiency of this process is closely linked to the composition of the biomass and, sometimes, characteristics of the initial matrix can impede the process. To address these challenges, various pretreatments are employed to enhance digestion efficiency and mitigate issues associated with biomass complexity. However, the implementation of pretreatments can be energy-intensive and costly. The extraction of valuable molecules from biomass for various applications can represent a form of pretreatment. This extraction process selectively removes recalcitrant molecules such as lignin and cellulose, which can hinder biodegradation, thereby adding new value to the biomass. These extracted molecules not only contribute to improved anaerobic digestion efficiency but also offer potential economic benefits by serving as valuable inputs across diverse industrial sectors. This article presents a detailed state of the art of the most widespread biomass pretreatments and specifies when biomass is pretreated to improve the biogas yield and, in contrast, when it is treated to extract high-added-value products. Finally, in order to define if the same treatment can be simultaneously applied for both goals, an experimental section was dedicated to the production of biogas from untreated olive mill wastewater and the same biomass after being freeze-dried and after the extraction of polyphenols and flavonoids. The use of pretreated biomass effectively improved the biogas production yield: the untreated olive mill wastewater led to the production of 147 mL of biogas, while after freeze-drying and after polyphenols/flavonoids extraction, the production was, respectively, equal to 169 mL and 268 mL of biogas. [ABSTRACT FROM AUTHOR]

Typically, citrus waste is composted on land by producers or used as livestock feed. However, the biorefinery approach offers a sustainable and economically viable solution for managing and valorizing these agricultural residues. This review examines research from the period 2014 to 2024. Citrus waste can be utilized initially by extracting the present phytochemicals and subsequently by producing value-added products using it as a raw material. The phytochemicals reported as extracted include essential oils (primarily limonene), pectin, polyphenolic components, micro- and nano-cellulose, proteins, and enzymes, among others. The components produced from the waste include bioethanol, biogas, volatile acids, biodiesel, microbial enzymes, and levulinic acid, among others. The review indicates that citrus waste has technical, economic, and environmental potential for utilization at the laboratory scale and, in some cases, at the pilot scale. However, research on refining pathways, optimization, and scalability must continue to be an active field of investigation. [ABSTRACT FROM AUTHOR]

Watermelon suffers substantial post-harvest losses owing to strict quality standards, resulting in 20–30% of the crop being left unharvested. This study investigated the potential of valorizing dried watermelon pomace (DWP), a byproduct of watermelon juice extraction, focusing on its lycopene content—a potent antioxidant. This study assessed lycopene stability in DWP from four watermelon cultivars (Perla Nera®, Gavina®, Crimson Sweet, and Asahi Miyako) under different storage conditions (vial-sealed and vacuum-sealed). The lycopene content in freshly prepared DWP samples ranged from 0.734 to 1.572 mg/g db. The results indicated that vacuum-sealed samples exhibited significantly slower lycopene degradation than vial-sealed samples, highlighting the impact of air exposure on lycopene stability. After 90 days of storage, lycopene content in vacuum-sealed samples ranged from 0.214 to 1.234 mg/g db, while that in vial-sealed samples ranged from 0.013 to 0.731 mg/g db. Furthermore, this study assessed the effect of pretreatments with ascorbic acid (pretreatment A) and a mixture of ascorbic and citric acids (pretreatment B) on lycopene stability. Pretreatment B showed superior effectiveness, yielding higher lycopene levels than pretreatment A (p < 0.05). The stabilizing effects of ascorbic acid and citric acid were attributed to their antioxidant properties and their roles as pH regulators and chelators. [ABSTRACT FROM AUTHOR]

This review examines the role of deep eutectic solvents (DESs) in the biorefinery process. It covers the characteristics and classification of two‐component DESs, their preparation methods, and their physicochemical properties. The various applications of DES systems in biomass pretreatment, including lignin and hemicellulose removal, production of cellulose nanofibers, and the extraction of proteins, lipids, and phenolic compounds, among others, are explored. The synthesis of platform molecules using DES is also discussed. Finally, this review provides some tools that may be useful for researching the involvement of DES systems in high‐ or low‐biomass biorefineries. [ABSTRACT FROM AUTHOR]

Dunaliella functions as a microscopic bioindustry that can capture atmospheric carbon dioxide and amass it into a range of economically viable compounds. Dunaliella‐based biorefineries have emerged as sustainable platforms for fostering a green economy and reducing carbon emissions. Dunaliella‐derived value‐added compounds are commercially important due to their application in the food, pharmaceutical, cosmeceutical, and nutraceutical sectors. The present study highlights the economic application of different Dunaliella species and the available sustainable technologies for the cultivation, harvesting, and extraction of bioactive compounds that have the potential for commercial scaleup. Their incorporation into biorefinery processes can reduce dependency on energy‐intensive and low‐yield processes. This review briefly discusses the technoeconomic analysis (TEA) of Dunaliella‐driven industrial approaches for the optimization of effective yield and determination of final production costs. The major algal biorefineries are operational in countries like Australia, China, India, Israel, Japan, Portugal, Spain and the USA. The authors have comprehensively deliberated different aspects of Dunaliella from physiological to industrial applications, meanwhile underscoring the existing knowledge gaps that impede the success of Dunaliella biorefineries. The current industrial methods being employed for biorefineries are limited to producing individual bioproducts, which may not be fully cost effective, making them less competitive in the global market. However, the analysis carried out can serve as a starting point and can guide stakeholders towards the future direction of Dunaliella‐based research and the circular bioeconomy. [ABSTRACT FROM AUTHOR]

Succinic acid is recognized as a key component in the production of various commercially important chemical commodities. Technical‐economic analysis can provide valuable insights into the feasibility of large‐scale biochemical production of succinic acid. In this study, the effects of scale on the design of a biorefinery using sugarcane bagasse were evaluated using a detailed process modeling methodology. Four processes were simulated and compared, three based on patents from biosuccinic acid (bio‐SA) manufacturing companies and one based on a process economic program report (PEP). This methodology allowed for the analysis of scale benefits for each technological route. A comprehensive economic evaluation was conducted by comparing the biochemical processes in terms of investment and production costs, as well as the minimum selling price (MSP) of bio‐SA. Results show that the MSP of more promising process designs ranged from 3105 to 2095 $ t−1, which is compatible with the cost of petrochemical‐based succinic acid. Moreover, for capacities above 90 kt year−1, the MSP remains virtually constant, and every process evaluated revealed a breakdown in the project economy of scale. A sensitivity and risk analysis was carried out to evaluate the impacts of several process parameters on the project's technoeconomic analysis, resulting in bio‐SA selling price and investment costs as parameters with the highest impact on economic viability. [ABSTRACT FROM AUTHOR]

A report on the Pithecellobium dulce tree is provided in this review. The main characteristics of the tree, its chemical composition, traditional applications and future application in the bioenergy area are addressed. Pithecellobium dulce is a leguminous tree characterized by being fast growing, nitrogen fixing and largely available. In addition, it is distinguished by growing in different types of soils from acid to alkaline and with little water. This review could serve as a scientific basis to promote and carry out new research work focused on individual and comprehensive use for various bioenergetic processes, from the different parts that make up the P. dulce tree such as its leaves, pods, branches, flowers, fruit and seeds. Among the bioenergetic processes that could be developed are the production of bioethanol, biodiesel, biogas, heterogeneous catalysts, biochar, activated carbon and nanoparticles, among other applications. [ABSTRACT FROM AUTHOR]

Biochar is recognized for its potential in mitigating climate change, especially through carbon sequestration and soil improvement. To this end, it is important to use all co-products from pyrolysis in a sustainable and economically viable way. In this study, the conversion of sugarcane bagasse at varying pyrolysis temperatures was investigated using 1H NMR spectroscopy and Chenomx for liquid fraction analysis. The yield of biochar decreased significantly from 45.3 to 3.5% with a temperature increase of 300 to 1000 °C. The morphological analysis revealed that biochar produced at lower temperatures (300 °C and 400 °C) showed tubular and spongy structures, whereas at higher temperatures (600 °C and 800 °C), the structures morphed into holes and thinned further, ultimately degrading further at 1000 °C. All samples of biochar showed characteristics promising for soil improvement and carbon sequestration (O/C < 0.4). The analysis of liquid fractions revealed that biomethanol reached its highest concentration of 19.28 mM at 800 °C, which coincided with the highest production of acetic and lactic acids. Additionally, the highest concentration of acetone was observed at 600 °C. These findings highlight the importance of optimizing pyrolysis conditions for enhanced yields of biochar and platform compounds, as well as the potential of the NMR and Chenomx in bioenergy research. [ABSTRACT FROM AUTHOR]

The prevailing extractive economic model is unsustainable due to the finite nature of resources, thereby necessitating the development of alternative models and policies. The anaerobic digestion (AD) process is key to achieving this objective, as it facilitates the conversion of organic waste into biogas and nutrient-rich digestate. This approach is aligned with the principles of a circular economy and contributes to a reduction in carbon emissions. This study aims to conduct a comprehensive bibliometric analysis of the literature published over the past three decades (1993–2023). The analysis will be based on data drawn from the Scopus database and then analysed using the VOSviewer software, which allows for the interconnection of the revised bibliography through a series of selected keywords. The results demonstrated the existence of four clusters: (i) the beneficial valorisation of waste; (ii) volatile fatty acids and biohydrogen as added value by-products resulting from AD; (iii) lignocellulosic substrates and their by-products; and iv) the main products of AD, biogas and digestate. The bibliometric analysis demonstrates a growing interest in AD within the biorefinery concept in recent years, showcasing its potential for effective waste management and integration into the production chain through the principles of the circular economy. [ABSTRACT FROM AUTHOR]

The guishe is a by-product of the fiber extraction from Agave lechuguilla. This material has no commercial value, although it contains metabolites that could be used as a resource for producing high-value products. This study optimized the DPPH• (2,2-diphenyl-1-picrylhydrazyl) antioxidant activity through microwave-assisted extraction (MAE) of polyphenolic compounds from Agave lechuguilla residues. The MAE process was optimized using a Box-Behnken design, with extraction time (5–15 min), temperature (40–50 °C), and solvent: sample ratio (1:20–1:30 m/v) as independent variables. In contrast, the dependent variable was DPPH• free radical scavenging activity. As a result, the highest antioxidant activity was at 8 min of irradiation, extraction temperature of 45 °C, and solvent: sample ratio 1:30 w/v, obtaining a total flavonoid content of 19.25 ± 0.60 mg QE/g DW, a total polyphenol content of 6.59 ± 0.31 mg GAE/g DW, a DPPH• free radical scavenging activity of 73.35 ± 1.90%, and an ABTS+• ([2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonate)]) free radical scavenging activity of 91.93 ± 0.68%. [ABSTRACT FROM AUTHOR]

Cassava, a staple food crop, is widely used for starch production, but its inconsistent supply, price volatility, and substantial waste generation pose challenges to the cassava industrial market's growth. This study aims to identify a sustainable biorefinery pathway by optimizing conventional cassava starch plants (business-as-usual, BAU) for economic and environmental benefits. Four scenarios were evaluated: animal feed from peel waste (Scenario 1), fungal protein from thippi waste (Scenario 2), fish feed from digested wastewater (Scenario 3), and conversion of all waste streams into animal feed, fish feed, and fungal protein (Scenario 4). Scenario 4 emerged as the best pathway using the multi-criteria decision-making (MCDM) approach, with a performance score of 0.282. Despite the highest energy consumption (18.91 MWh), Scenario 4 was favored for producing four value-added products alongside starch, yielding the highest profit at USD 8.85 million. In contrast, profits for BAU, Scenario 1, Scenario 2, and Scenario 3 were 1.91, 2.30, 5.01, and USD 8.79 million, respectively. Waste valorization in Scenarios 1, 2, 3, and 4 resulted in CO2 avoidance of 36.5., 42.6., 21.7, and 57.45 t CO2eq., respectively. However, producing value-added products increased energy consumption by 13, 73, 7, and 74% compared to BAU (4.58 MWh). The global warming potential analysis showed negative values for scenarios 2 and 4, at -436 and -434 kg CO2eq./t root, respectively. This study highlights the potential of a biorefinery approach for sustainable cassava starch production, providing insights for future research and policy development. [ABSTRACT FROM AUTHOR]

Converting carbohydrates into 5-hydroxymethylfurfural (5-HMF) is an attractive and promising route for value-added utilization of agricultural and forestry biomass resource. As an important platform compound, 5-HMF possesses high active furan structure with hydroxymethyl and aldehyde group for production of various bio-chemicals and materials, meanwhile, which suffer from low stability and poor yield during the industrial biorefinery process. Hence, selective production of 5-HMF with high-yield and low-cost has attracted extensive attention from scientific and industrial researchers. This review sorted and described the latest advanced research on solvent and catalyst system, as well as energy field effect for production of 5-HMF with different feedstock in detail, emphatically discussing the solvent effect and its synergistic effect with other aspects. Besides, the future prospects and challenges for production of 5-HMF from carbohydrates were also presented, which provide a profound insight into industrial 5-HMF process with economic and environmental feature. [ABSTRACT FROM AUTHOR]

A simple two-stage extraction and recovery method for macromolecules from microalgae biomass, termed CASS (concentrating the microalgae solution, acid pretreatment, high-shear-assisted lipid extraction, and separation), was developed. This method effectively processed the wet biomass of Chlorella sp. ABC-001 at a moderately low biomass concentration (50 g/L). The optimal conditions were acid pretreatment with 5 wt.% H2SO4 at 100 °C for 1 h, followed by high-shear extraction using hexane at 3000 rpm for 30 min. The acid pretreatment hydrolyzed carbohydrates and phospholipids, disrupting the cell wall and membrane, while high-shear mixing enhanced mass transfer rates between solvents and lipids, overcoming the hydraulic barrier at the cell surface. Within 10 min after completing the process, the extraction mixture achieved natural phase separation into water, solvent, and biomass residue layers, each enriched with carbohydrates, lipids, and proteins, respectively. The CASS process demonstrated high esterifiable lipid yields (91%), along with substantial recovery of glucose (90%) and proteins (100%). The stable phase separation prevented emulsion formation, simplifying downstream processing. This study presents the results on cell disruption, optimal acid treatment concentration, and high-shear mixing to achieve macromolecule separation, expanding the lipid-centric microalgal process to a comprehensive biorefinery concept. [ABSTRACT FROM AUTHOR]

Abstract Background Biorefinery using microorganisms to produce biofuels and value-added biochemicals derived from renewable biomass offers a promising alternative to meet our sustainable energy and environmental goals. The ethanologenic strain Zymomonas mobilis is considered as an excellent chassis for constructing microbial cell factories for diverse biochemicals due to its outstanding industrial characteristics in ethanol production, high specific productivity, and Generally Recognized as Safe (GRAS) status. Nonetheless, the restricted substrate range constrains its application. Results The truncated ice nucleation protein InaK from Pseudomonas syringae was used as an autotransporter passenger, and α-amylase was fused to the C- terminal of InaK to equip the ethanol-producing bacterium with the capability to ferment renewable biomass. Western blot and flow cytometry analysis confirmed that the amylase was situated on the outer membrane. Whole-cell activity assays demonstrated that the amylase maintained its activity on the cell surface. The recombinant Z. mobilis facilitated the hydrolysis of starch into oligosaccharides and enabled the streamlining of simultaneous saccharification and fermentation (SSF) processes. In a 5% starch medium under SSF, recombinant strains containing P eno reached a maximum titer of 13.61 ± 0.12 g/L within 48 h. This represents an increase of 111.0% compared to the control strain's titer of titer of 6.45 ± 0.25 g/L. Conclusions By fusing the truncated ice nucleation protein InaK with α-amylase, we achieved efficient expression and surface display of the enzyme on Z. mobilis. This fusion protein exhibited remarkable enzymatic activity. Its presence enabled a cost-effective bioproduction process using starch as the sole carbon source, and it significantly reduced the required cycle time for SSF. This study not only provides an excellent Z. mobilis chassis for sustainable bioproduction from starch but also highlights the potential of Z. mobilis to function as an effective cellular factory for producing high-value products from renewable biomass.

The global spread of invasive plants is an important environmental problem and a real threat to biological diversity, with significant impacts on agriculture, forestry, and human and animal health. Invasive plant eradication produces large amounts of plant biomass, which should be safely utilized. The study reviews possibilities for using biomass of invasive plant species in the bioeconomy to safely convert them to items of value. Invasive plant biomass can be used as fuel or for energy production applying either biochemical or thermochemical processing technologies. The biomass of invasive plants also can be used for energy production or isolation of biologically active components. Invasive plants contain many groups of substances providing their defense potential against predators; these substances participate in metabolic regulation processes and others. Amongst the substances of interest for bioeconomy are lipids, polyphenols, alkaloids, carbohydrates, plant fibers, and essential oils. In the development of invasive plant biomass utilization strategies, the bio-based value pyramid and the waste hierarchy should be considered. Scientific sound strategies of invasive plant management will limit their spread and provide economic benefits via their eradication.

Abstract Lignin, the second most abundant renewable carbon source on earth, holds significant potential for producing biobased specialty chemicals. However, its complex, highly branched structure, consisting of phenylpropanoic units and strong carbon-carbon and ether bonds, makes it highly resistant to depolymerisation. This recalcitrancy highlights the need to search for robust lignin-degrading microorganisms with potential for use as industrial strains. Bioprospecting for microorganisms from lignin-rich niches is an attractive approach among others. Here, we explored the ligninolytic potential of bacteria isolated from a lignin-rich underground coalmine, the Morupule Coal Mine, in Botswana. Using a culture-dependent approach, we screened for the presence of bacteria that could grow on 2.5% kraft lignin-supplemented media and identified them using 16 S rRNA sequencing. The potential ligninolytic isolates were evaluated for their ability to tolerate industry-associated stressors. We report the isolation of twelve isolates with ligninolytic abilities. Of these, 25% (3) isolates exhibited varying robust ligninolytic ability and tolerance to various industrial stressors. The molecular identification revealed that the isolates belonged to the Enterobacter genus. Two of three isolates had a 16 S rRNA sequence lower than the identity threshold indicating potentially novel species pending further taxonomic review. ATR-FTIR analysis revealed the ligninolytic properties of the isolates by demonstrating structural alterations in lignin, indicating potential KL degradation, while Py-GC/MS identified the resulting biochemicals. These isolates produced chemicals of diverse functional groups and monomers as revealed by both methods. The use of coalmine-associated ligninolytic bacteria in biorefineries has potential.