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Plant hormones regulate adaptive responses to various biotic and abiotic stress factors. Applied exogenously, they trigger the natural plant defense mechanisms, a feature that could be implemented in strategies for supporting crop resilience. The potential of the exogenous cytokinin-like acting compound (kinetin), the auxin analogue 1-naphtyl acetic acid (NAA), abscisic acid (ABA) and the ethyleneprecursor 1-aminocyclopropane-1-carboxylic acid (ACC) to mitigate dehydration was tested on Lactuca sativa (lettuce) grown on 12% polyethylene glycol (PEG). Priming with different blends containing these plant growth regulators (PGRs) applied in bioequivalent concentrations was evaluated through biometric measurements and biochemical analyses. The combined treatment with the four compounds exhibited the best dehydration protective effect. The antioxidative enzyme profiling of the PGR-primed individuals revealed increased superoxide dismutase (SOD), catalase and peroxidase activity in the leaves. Immunodetection of higher levels of the rate-limiting enzyme for proline biosynthesis (delta-pyroline-5-carboxylate synthase) in the primed plants coincided with a significantly higher content of the amino acid measured in the leaves. These plants also accumulated particular dehydrin types, which may have contributed to the observed stress-relieving effect. The four-component mix applied by spraying or through the roots exerted similar stress-mitigating properties on soil-grown lettuce subjected to moderate drought. [ABSTRACT FROM AUTHOR]

Three pretreatment methods including calcination, carbonization, and a carbonization-calcination combined pretreatment were studied to understand the pretreatment mechanisms for cement-based recycled powder (CRP). The mineral and microstructure of the CRP sample were investigated through X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), thermal gravity (TG) analysis, and scanning electron microscopy (SEM) after exposure to different thermal temperatures (400 °C, 600 °C, and 800 °C), carbonization times (6 h, 1 d, and 3 d), and pre-carbonization for 1 d followed by heating at 800 °C. The results showed that the optimal thermal pretreatment temperature was approximately 720–800 °C. Through the process of calcination, the C-S-H, Ca(OH)2, and CaCO3 minerals in the CRP sample underwent decomposition to produce CaO or C2S. During carbonation, the pretreatment not only results in the increased production of CaCO3 owing to the reaction of the C-S-H gel and Ca(OH)2 with CO2, but also enhances its properties and the strength of chemical bond between CaCO3 and the post-hydration products. Both CaCO3 and CaO were present after the combined pretreatment, which indicates that the CaCO3 mineral formed superior stability after it had been pre-carbonated. Due to fewer impurities in CRP, the positive effect of the pretreatment on CRP was significantly better than that on recycled powder derived from construction and demolition waste. [ABSTRACT FROM AUTHOR]

Although straw is being utilized as an additive in construction materials, the thermal properties of straw and building materials in combination are insufficient. The thermal properties of straw–mortar composite materials can be improved by the pretreatment of straw. The alkali treatment enhances the mechanical attachment between the fibers and the matrix material, assuring that the straw–mortar composite materials have solid thermal insulation characteristics. Pretreatment with sodium hydroxide was utilized in this work to enhance the thermal properties of straw–mortar composite materials. This study mainly investigated the thermal properties of straw–mortar composite material after sodium hydroxide pretreatment and its change rules under the condition of the freeze–thaw cycle. A three-factor, three-level Box–Behnken experimental design, with the straw content (%), pretreatment time (min), and reagent concentration (%) as process parameters, was used. The response variables were the thermal conductivity, thermal diffusivity, and thermal resistance. The findings revealed that all of the variables had a substantial impact on the replies. Optimization parameters of 17.95% for the straw content, 19.50 min for the pretreatment time, and 4.99% for the reagent concentration for the straw–mortar composite materials were achieved. A thermal conductivity of 0.211 W·(m·K)−1, a thermal diffusivity of 0.277 mm2·s−1, and a thermal resistance of 57.211 K·W−1 were the optimal thermal property indices. Furthermore, during the freeze–thaw cycle, the thermal conductivity coefficient and thermal diffusion coefficient of the combined pretreatment composite were 26% and 9% lower than the materials without the treatment. The thermal performance of the mortar composites prepared by alkali-treated straw was better than that prepared by untreated straw. [ABSTRACT FROM AUTHOR]

A novel pretreatment strategy utilizing a combination of NaOH and 1-Butyl-3-methylimidazolium chloride ([Bmim]Cl) was proposed to enhance the enzymatic hydrolysis of abandoned Medium-density fiberboard (MDF). The synergistic effect of NaOH and [Bmim]Cl pretreatment significantly improved the glucose yield, reaching 445.8 mg/g within 72 h, which was 5.04 times higher than that of the untreated samples. The working mechanism was elucidated according to chemical composition, as well as FTIR, 13C NMR, XRD, and SEM analyses. The combined effects of NaOH and [Bmim]Cl led to lignin degradation, hemicellulose removal, the destruction and erosion of crystalline regions, pores, and an irregular microscopic morphology. In addition, by comparing the enzymatic hydrolysis sugar yield and elemental nitrogen content of untreated MDF samples, eucalyptus, and hot mill fibers (HMF), it was demonstrated that the presence of adhesives and additives in waste MDF significantly influences its hydrolysis process. The sugar yield of untreated MDF samples (88.5 mg/g) was compared with those subjected to hydrothermal pretreatment (183.2 mg/g), Ionic liquid (IL) pretreatment (406.1 mg/g), and microwave-assisted ionic liquid pretreatment (MWI) (281.3 mg/g). A long water bath pretreatment can reduce the effect of adhesives and additives on the enzymatic hydrolysis of waste MDF. The sugar yield produced by the combined pretreatment proposed in this study and the removal ability of adhesives and additives highlight the great potential of our pretreatment technology in the recycling of waste fiberboard. [ABSTRACT FROM AUTHOR]

A combined pretreatment method of "low temperature-ultrasound-papain" (LTUP) was proposed to remove the purine of pork loins. Compared with untreated pork loin, under optimal conditions (temperature 58 °C, ultrasound density 100 W/cm2, and papain concentration 0.085%), the purine removal rate of treated pork loin could reach 59.29 ± 1.39%. The meat quality of pork loin treated with the LTUP method such as hardness and chewiness decreased by 58.37% and 64.38%, respectively, and the in vitro protein digestibility was increased by 19.64%; the cooking loss was decreased by 15.45%, compared with the simulated household blanching process (HT). In view of the high purine removal rate, the losses of free amino acids and soluble peptides were acceptable and reasonable. SEM and LF-NMR results showed that low temperature and ultrasound combined with papain treatment opened a channel for purine transfer and promoted purine dissolution by affecting the protein structure of pork loin. In addition, the migration of water within the muscle tissue was also related to purine removal. In summary, LTUP is recommended as an efficient and green way for the meat industry to remove purine. [ABSTRACT FROM AUTHOR]

Sunflower husk (SFH) contributes 45–60% of the total sunflower seed weight and is a by-product of the sunflower oil industry. Among other elements, SFH ash contains K, Na, Ca and Mg. These elements cause rapid growth of ash deposits on convective heating surfaces of the boiler, resulting in reduced efficiency. The aim of this paper is to examine the possibility of producing quality fuel from SFH by its pretreatment with the technique of torrefaction in a fluidized bed in superheated water vapor. Continuous monitoring of the innovative SFH torrefaction process allowed for the determination of optimal process durations. SFH could be converted into a biofuel, having high calorific value and suitable characteristics for co-combustion with coal. Furthermore, the torrefaction in a fluidized bed of superheated water vapor allowed for a 6-fold reduction in the required process duration in comparison with data reported from the literature for the process of torrefaction in a dense bed, along with a 3-fold reduction in the chlorine content in SFH ash. These effects are beneficial to resolve the problem of corrosion on convective heating surfaces of boilers. However, torrefaction in superheated water vapor did not significantly reduce the content of alkaline and alkaline-earth elements in SFH ash. Still, this issue may be alleviated by significantly increasing the duration of SFH pretreatment. [ABSTRACT FROM AUTHOR]

Mandarin peel (MP) has gained attention as a feedstock for flavonoid recovery via the extraction process based on the biorefinery concept, but residues remain after the extraction. Toward an integrated biorefinery concept, this study aimed to valorize extracted MP (eMP) by using it in bioethanol production. For efficient fermentable sugar production, the effect of enzymatic hydrolysis conditions on sugar conversion from eMP was investigated, and the results showed that combining cellulase and cellobiase resulted in a higher enzymatic glucose conversion (78.2%) than the use of the individual enzymes (37.5% and 45.6%). Pectinase played an essential role in enhancing enzymatic arabinose conversion, and the optimal conditions were determined to be pH 4 and 90 units of the three enzymes. Under optimal conditions, the sugar yield was 199 g glucose and 47 g arabinose/kg eMP, and the hydrolysate was used in bioethanol fermentation. The results showed that the bioethanol production was 3.78 g/L (73.9% yield), similar to the control medium (3.79 g/L; 74.2% yield), although the cell growth of the yeast was slightly delayed in the eMP hydrolysate medium. This study highlights the potential of eMP as a low-cost feedstock for sugar and bioethanol production. [ABSTRACT FROM AUTHOR]

Plant-based waste biomass with lignocellulose as an important component is produced in large quantities worldwide every year. The components of lignocellulose that typically exhibit high utilization value include cellulose and hemicellulose, as well as pentoses and hexoses derived from their hydrolysis. As a pretreatment for the hydrolysis process, delignification is a pivotal step to enhance cellulose/hemicellulose accessibility and achieve high yields of fermentable sugars. Additionally, deep eutectic solvents (DESs) are the most widely used solvents for delignification during biomass fractionation due to their clean and environmentally friendly attributes. DESs dissolve lignin by inducing a large amount of β-O-4 bond cleavage and partial carbon–carbon bond cleavage, retaining cellulose in the solid residue, while most of the hemicellulose is hydrolyzed in DES pretreatment. This article provides a comprehensive review of the influence of DESs in the lignocellulose separation process. Key factors such as lignin removal rate, sugar conversion rate, and product chemical structure are critically reviewed to assess the feasibility of employing DESs for lignocellulose separation. [ABSTRACT FROM AUTHOR]

With the increasingly serious problems of energy shortage and environmental degradation, countries around the world are actively developing safe, environmentally friendly, and renewable energy. Biomass energy has become an ideal substitute for fossil fuels due to its abundant reserves, good renewable performance, and zero carbon emissions. This paper discusses the importance and potential of biomass energy as a renewable energy source for China's energy development, mainly including the three biomass conversion methods of physics, chemistry, and biology, seven utilization technologies, such as direct combustion, gasification, and pyrolysis, and five application approaches, such as biomass power generation, biomass gas fuel, biomass liquid fuel, and bio-based materials. This review systematically analyzes the challenges faced by China's development of biomass energy and discusses the future development direction of biomass. The utilization of biomass resources should take a comprehensive and high-value path. China is actively looking for new energy utilization paths, and biomass energy has become a key measure to cope with carbon emission reduction, climate change, and ecological environment protection. [ABSTRACT FROM AUTHOR]

The effective management of waste-activated sludge (WAS) presents a significant challenge for wastewater treatment plants (WWTPs), primarily due to the sludge's high content of organic matter, pathogens, and hazardous substances such as heavy metals. As urban populations and industrial activities expand, the increasing volume of WAS has intensified the need for sustainable treatment solutions. Conventional approaches, such as landfilling and anaerobic digestion, are frequently ineffective and resource-intensive, particularly when dealing with the protective extracellular polymeric substances (EPS) that render WAS resistant to biodegradation. Thermal pretreatment methods have gained attention due to their ability to enhance the biodegradability of sludge, improve dewaterability, and facilitate resource recovery. These processes function by breaking down complex organic structures within the sludge, thereby increasing its accessibility for subsequent treatments such as anaerobic digestion. The integration of thermal treatment with chemical methods can further optimize the management process, resulting in higher biogas yields, reduced pathogen content, and lower environmental risks. While thermal disintegration is energy-intensive, advancements in energy recovery and process optimization have made it a more viable and environmentally friendly option. This approach offers a pathway to more sustainable and efficient sludge management practices, which align with the goals of reducing waste and complying with stricter environmental regulations. [ABSTRACT FROM AUTHOR]

Wastewater treatment plants generate significant amounts of sludge, a residual product that is rich in nutrients, usually considered waste, and traditionally eliminated by storage or incineration, methods that are expensive, environmentally damaging, and often unsustainable. Composting is increasingly recognized as an ecological and durable solution for managing biodegradable waste, including sludge resulting from wastewater treatment. The composting of residual sludge usually requires mixing with bulking agents, such as green waste or agricultural residues, to ensure a well-balanced carbon–nitrogen ratio. This mixture undergoes a controlled aerobic decomposition, sometimes followed by post-treatment, resulting in a stabilized final product that is nutrient-rich and pathogen-free and can be used as soil amendment or fertilizer in different agricultural or landscaping applications. By using composting, communities can reduce elimination costs, reduce greenhouse gas emissions, and minimize the environmental impact of sludge management. This paper reviews recent reported experiences in the laboratory regarding full-scale sludge composting, highlighting the particularities of the processes, the influence factors, the quality of the final product, and the environmental and regulatory constraints. Composting is a sustainable and ecological solution for managing wastewater sludge, contributing to nutrient circularity, and minimizing the environmental impact. [ABSTRACT FROM AUTHOR]

Circular economy and sustainability are pivotal concepts in the discourse on the synergies between economic growth and environmental impact. As resource scarcity and environmental degradation intensify, advancements in energy conversion technologies become crucial for a sustainable economic model. Currently dependent on fossil fuels, the global economy must shift to a sustainable framework focused on bioenergy. Biomass, a renewable energy source, offers a promising solution by converting waste into valuable resources, reducing waste and environmental impact, and creating economic opportunities. Biofuels and bioproducts can meet energy needs while reducing greenhouse gas emissions and addressing global warming. Recent advances in biofuels, supported by initiatives and policies, promote more sustainable energy production. This paper aims to highlight the potential of biomass in meeting contemporary energy demand and provides an overview of biofuels and their production as a renewable alternative to fossil fuels. It also explores the future of agriculture and energy sectors, emphasizing global energy and environmental challenges and the competition between food and fuel feedstocks. [ABSTRACT FROM AUTHOR]

Methane and hydrogen generated from waste and biomass are renewable resources, which may successfully replace traditional fossil fuels. This paper investigates the enhancement effect of lignocellulosic biomass pretreatment on dark fermentative hydrogen production from sugar beet pulp (SBP). The results showed that sugar beet pulp after pretreatment contained significant amounts of unfermented sugars (mainly glucose, arabinose, galactose, and raffinose), and, therefore, represented an attractive substrate for methane and hydrogen production. The greatest methane yield (495 dm3 CH4/kg VS) was achieved from sugar beet pulp after alkaline pretreatment. High methane production of up to 445 dm3 CH4/kg VS was also obtained using acidic and enzymatic hydrolysis as a preliminary treatment of the pulp. All the pretreatment methods also resulted in the enhancement of hydrogen yield with the highest value of 229 dm3 H2/kg VS achieved using acid hydrolysis compared with 17 dm3 H2/kg VS for raw material subjected to digestion. [ABSTRACT FROM AUTHOR]

The anaerobic digestion of wastewater treatment sludge (WAS) produces a "green" biogas while reducing the amount of residual sludge. To increase the yield of biogas, several individual or combined pre-treatment methods of WAS can be used. These pre-treatment methods substantially reduce the amount of volatile suspended solids (VSSs) and their associated total chemical oxygen demand (TCOD). Pre-treating the sludge will increase the methane yield by 15 to 30%. Although the individual methods have been dealt with in research and large-scale operations, the combined (hybrid) methods have not previously been reviewed. Here, different hybrid treatment methods are reviewed, including (1) thermochemical hydrolysis pre-treatment, using an alkaline or acid addition to enhance solubilization of the sludge cells and increase biogas production; (2) alkaline and high-pressure homogenizer pre-treatment, combining a chemical and mechanical treatment; (3) alkaline and ultrasound pre-treatment, capable of solubilizing organic sludge compounds by different mechanisms, such as the fast and effective ultrasound disruption of cells and the increasing effect of the alkaline (NaOH) treatment; (4) combined alkaline and microwave pre-treatment, which enhances sludge solubilization by at least 20% in comparison with the performance of each separate process; (5) microwave (MW) and peroxidation pre-treatment of WAS suspended solids (SSs), which are quickly (<5 min) disintegrated by MW irradiation at 80 °C; (6) ultrasound and peroxidation pre-treatment, with ozone and peroxides as powerful oxidizing agents; and (7) pulsed electric field (PEF) pretreatment. All literature findings are assessed, discussing relevant operation conditions and the results achieved. [ABSTRACT FROM AUTHOR]

The increasing demand for sustainable agricultural practices aimed at reducing carbon dioxide emissions has driven the exploration of converting viticulture residues into biochar. This study investigates the potential technological applications of biochar as a filler for the production of electrically conductive composite materials, suitable to Bipolar Plate (BP) manufacturing. Grape seeds (GSs), defatted grape seeds (DGSs), wood stems (WSs), and whole grape seeds (WGSs) were converted into biochar samples through low-temperature (300 °C) pyrolysis for 3 or 24 h. The composition and thermal stability of biochar were evaluated through thermogravimetric analysis (TG), which provided valuable insights into interpreting the in-plane conductivity (IPC) values of the BP samples. Pyrolyzed GS and DGS biochar samples demonstrated enhanced thermal stability and conferred higher IPC values compared to WS counterparts. This indicates a clear correlation between the formation of carbon-rich structures during pyrolysis and overall electrical conductivity. In contrast, pyrolyzed WGSs produced BP samples with lower IPC values due to the presence of lipids, which were not effectively degraded by the low-temperature pyrolysis. [ABSTRACT FROM AUTHOR]

In this experiment, we explored the chemical composition and community structure of Mulberry "Wuhedashi" (Morus alba L., hereinafter referred to as WHDS) in different stages and obtained data support for its resource utilisation. Five ripening stages were established: S1, deep-red stage; S2, red with black stage; S3, black with red stage; S4, black stage; S5, overripe stage. The results showed that there were significant differences in the indicators of WHDS in the different stages. Immature WHDS contains high levels of amino acids (2.14 ± 0.15 mg/g), organic acids (43.10 ± 0.75 mg/g), K (3019.52 ± 78.00 mg/L), and Ca (1617.86 ± 24.45 mg/L) and is an important source of amino acid and mineral supplementation for the body. Total phenolic compounds (26.15 ± 0.43 g/L), total flavonoids (2.46 ± 0.03 g/L), total anthocyanins (587.60 ± 7.38 mg/L), the ABTS radical scavenging rate (94.20 ± 2.18%), the DPPH radical scavenging rate (95.13 ± 1.44%), and total flavour compounds (1279.09 ± 33.50 mg/L) peaked at S4, which is the optimal stage for the consumption and processing of WHDS. High-throughput sequencing identified 10 dominant genera, including Bacillus, Brevibacterium, Pseudomonas, and Tatumella. Nesterenkonia was the most highly associated micro-organism. Bacterial genera such as Pantoea and Pseudomonas were significantly positively correlated with esters, enhancing the floral and fruity flavours of wine. The results of the study revealed the characteristics of WHDS in different stages, which can help to target the development of nutritious mulberry derivatives and provide a reference for enhancing the added value of mulberry. [ABSTRACT FROM AUTHOR]

Background: Propensity score matching (PSM) was used to investigate the prognostic value of a novel GLUCAR index [Glucose × (C-reactive protein ÷ albumin)] in unresectable locally advanced pancreatic cancer (LA-NPC) patients who received definitive concurrent chemoradiotherapy (CCRT). Methods: The PSM analysis comprised 142 LA-PAC patients subjected to definitive CCRT. Receiver operating characteristic (ROC) curve analysis was utilized to identify relevant pre-CCRT cutoffs that could effectively stratify survival results. The primary and secondary objectives were the correlations between the pre-CCRT GLUCAR measures and overall survival (OS) and progression-free survival (PFS). Results: The ROC analysis revealed significance at 43.3 for PFS [area under the curve (AUC): 85.1%; sensitivity: 76.8%; specificity: 74.2%; J-index: 0.510)] and 42.8 for OS (AUC: 81.8%; sensitivity: 74.2%; specificity: 71.7%; J-index: 0.459). Given that these cutoff points were close, the standard cutoff point, 42.8, was selected for further analysis. Comparative survival analyses showed that pre-CCRT GLUCAR ≥ 42.8 (n = 71) measures were associated with significantly shorter median PFS (4.7 vs. 15.8 months; p < 0.001) and OS (10.1 vs. 25.4 months; p < 0.001) durations compared to GLUCAR < 42.8 measures (n = 71). The multivariate analysis results confirmed the independent significance of the GLUCAR index on PFS (p < 0.001) and OS (p < 0.001) outcomes. Conclusions: Elevated pre-CCRT GLUCAR levels are robustly and independently linked to significantly poorer PFS and OS outcomes in unresectable LA-PAC patients treated with definitive CCRT. [ABSTRACT FROM AUTHOR]

Psychrophilic anaerobic digestion emerges as an appealing integrated solution for the management of agricultural waste, particularly for farmers in regions where the average temperature does not exceed 26 °C, as seen in coffee cultivation. Therefore, this study seeks to assess the biomethane potential of thermochemical-treated coffee husk through psychrophilic anaerobic digestion (C3-20 °C-w/pretreatment). To examine its viability, outcomes were compared with reactors operating at both mesophilic (C1-35 °C) and psychrophilic (C2-20 °C) conditions, albeit without the use of pretreated coffee husk. The C3-20 °C-w/pretreatment test demonstrated a 36.89% increase (150.47 NmL CH4/g VS; 161.04 NmL CH4/g COD), while the C1-35 °C test exhibited a 24.03% increase (124.99 NmL CH4/g VS; 133.77 NmL CH4/g COD), both in comparison to the C2-20 °C test (94.96 NmL CH4/g VS; 101.63 NmL CH4/g COD). Notably, the C3-20 °C-w/pretreatment trial yielded superior outcomes, accompanied by an associated energy output of 3199.25 GWh/year, sufficient to meet the annual energy demands of 494 residences. This marks an increase of 83 and 182 million residences compared to the mesophilic and psychrophilic AD of CH without pretreatment, respectively. [ABSTRACT FROM AUTHOR]

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

The quality of chrysanthemum tea has a great connection with its variety. Different types of chrysanthemum tea have very different efficacies and functions. Moreover, the discrimination of chrysanthemum tea varieties is a significant issue in the tea industry. Therefore, to correctly and non-destructively categorize chrysanthemum tea samples, this study attempted to design a novel feature extraction method based on the fuzzy set theory and improved direct linear discriminant analysis (IDLDA), called fuzzy IDLDA (FIDLDA), for extracting the discriminant features from the near-infrared (NIR) spectral data of chrysanthemum tea. To start with, a portable NIR spectrometer was used to collect NIR data for five varieties of chrysanthemum tea, totaling 400 samples. Secondly, the raw NIR spectra were processed by four different pretreatment methods to reduce noise and redundant data. Thirdly, NIR data dimensionality reduction was performed by principal component analysis (PCA). Fourthly, feature extraction from the NIR spectra was performed by linear discriminant analysis (LDA), IDLDA, and FIDLDA. Finally, the K-nearest neighbor (KNN) algorithm was applied to evaluate the classification accuracy of the discrimination system. The experimental results show that the discrimination accuracies of LDA, IDLDA, and FIDLDA could reach 87.2%, 94.4%, and 99.2%, respectively. Therefore, the combination of near-infrared spectroscopy and FIDLDA has great application potential and prospects in the field of nondestructive discrimination of chrysanthemum tea varieties. [ABSTRACT FROM AUTHOR]

The Jerusalem artichoke (Helianthus tuberosus) is a high-yield crop, and a great source of fermentable sugars, which gives the plant the potential to be used as raw material for economical fuel alcohol production. In this article, the authors focus on the technological aspect of the biofuel manufacturing process and its properties. First, the fuel alcohol manufacturing process is described, afterwards assessing its characteristics such as kinematic viscosity, density and octane number. The amount of fuel alcohol obtained from 10 kg of biomass equals to 0.85 L. Afterwards, the mixtures of gasoline and obtained fuel alcohol are prepared and studied. Optimal alcohol and gasoline mixtures are determined to obtain biofuels with octane ratings of 92, 95 and 98. The kinematic viscosity of obtained mixtures does not differ significantly from its values for pure gasoline. The obtained biofuel mixture with 25% alcohol content yielded a decrease of sulfur content by 38%, an increase of vaporized fuel amount by 17.5% at 70 °C and by 10.5% at a temperature of 100 °C, which improves engine startup time and ensures its stable operation in comparison to pure gasoline. The alcohol obtained can be successfully used as a high-octane additive for gasolines. [ABSTRACT FROM AUTHOR]

In this study, the release of proteins and other biomolecules into an aqueous media from two red macroalgae (Sphaerococcus coronopifolius and Gelidium spinosum) was studied using eight different cell disruption techniques. The contents of carbohydrates, pigments, and phenolic compounds coextracted with proteins were quantified. In addition, morphological changes at the cellular level in response to the different pretreatment methods were observed by an optical microscope. Finally, the antioxidant capacity of obtained protein extracts was evaluated using three in vitro tests. For both S. coronopifolius and G. spinosum, ultrasonication for 60 min proved to be the most effective technique for protein extraction, yielding values of 3.46 ± 0.06 mg/g DW and 9.73 ± 0.41 mg/g DW, respectively. Furthermore, the highest total contents of phenolic compounds, flavonoids, and carbohydrates were also recorded with the same method. However, the highest pigment contents were found with ultrasonication for 15 min. Interestingly, relatively high antioxidant activities like radical scavenging activity (31.57–65.16%), reducing power (0.51–1.70, OD at 700 nm), and ferrous iron-chelating activity (28.76–61.37%) were exerted by the different protein extracts whatever the pretreatment method applied. This antioxidant potency could be attributed to the presence of polyphenolic compounds, pigments, and/or other bioactive substances in these extracts. Among all the used techniques, ultrasonication pretreatment for 60 min appears to be the most efficient method in terms of destroying the macroalgae cell wall and extracting the molecules of interest, especially proteins. The protein fractions derived from the two red macroalgae under these conditions were precipitated with ammonium sulfate, lyophilized, and their molecular weight distribution was determined using SDS-PAGE. Our results showed that the major protein bands were observed between 25 kDa and 60 kDa for S. coronopifolius and ranged from 20 kDa to 150 kDa for G. spinosum. These findings indicated that ultrasonication for 60 min could be sufficient to disrupt the algae cells for obtaining protein-rich extracts with promising biological properties, especially antioxidant activity. [ABSTRACT FROM AUTHOR]

The conversion of lignocellulosic agricultural waste into biofuels and other economically valuable compounds can reduce dependence on fossil fuels, reduce harmful gas emissions, support the sustainability of natural resources, including water, and minimize the amount of waste in landfills, thus reducing environmental degradation. In this paper, the conversion of agricultural wastes into biomethane, biohydrogen, biodiesel, bioethanol, biobutanol, and bio-oil is reviewed, with special emphasis on primary and secondary agricultural residues as substrates. Some novel approaches are mentioned that offer opportunities to increase the efficiency of waste valorization, e.g., hybrid systems. In addition to physical, chemical, and biological pretreatment of waste, some combined methods to mitigate the negative effects of various recalcitrant compounds on waste processing (alkali-assisted thermal pretreatment, thermal hydrolysis pretreatment, and alkali pretreatment combined with bioaugmentation) are evaluated. In addition, the production of volatile fatty acids, polyhydroxyalkanoates, biochar, hydrochar, cellulosic nanomaterials, and selected platform chemicals from lignocellulosic waste is described. Finally, the potential uses of biofuels and other recovered products are discussed. [ABSTRACT FROM AUTHOR]

Hemicellulose can be selectively removed by acid pretreatment. In this study, selective removal of hemicellulose was achieved using dilute sulfuric acid assisted by aluminum sulfate pretreatment. The optimal pretreatment conditions were 160 °C, 1.5 wt% aluminum sulfate, 0.7 wt% dilute sulfuric acid, and 40 min. A component analysis showed that the removal rate of hemicellulose and lignin reached 98.05% and 9.01%, respectively, which indicated that hemicellulose was removed with high selectivity by dilute sulfuric acid assisted by aluminum sulfate pretreatment. Structural characterizations (SEM, FTIR, BET, TGA, and XRD) showed that pretreatment changed the roughness, crystallinity, pore size, and functional groups of corn straw, which was beneficial to improve the efficiency of enzymatic hydrolysis. This study provides a new approach for the high-selectivity separation of hemicellulose, thereby offering novel insights for its subsequent high-value utilization. [ABSTRACT FROM AUTHOR]

Currently, the transportation sector represents about one third of the total energy consumed in the world, most of this energy being obtained almost exclusively from oil. However, the world is changing, as well as the aviation industry. Since lignocellulosic biomass is a low-cost feedstock that does not compete with food, it has drawn great attention as one of the most attractive alternatives to replace fossil feedstocks for the production of fuels. Renewable jet fuels could have a significant impact on lowering greenhouse gas emissions and providing a long-term sustainable alternative to petroleum-derived fuels. However, the catalytic upgrading of lignocellulosic residues in industry still remains a big challenge and the development of highly integrated systems that allow the direct conversion of lignocellulosic wastes is essential to achieve that goal. The importance of renewable jet fuels and the potential of lignocellulosic biomass have already been extensively reviewed. However, this work presents a new perspective on the main catalytic routes and challenges for the sustainable production of aviation fuels from biomass wastes. [ABSTRACT FROM AUTHOR]

The production of municipal sludge is steadily increasing in line with the production of sewage. A wealth of organic contaminants, including nutrients and energy, are present in municipal sludge. Anaerobic fermentation can be used to extract useful resources from sludge, producing hydrogen, methane, short-chain fatty acids, and, via further chain elongation, medium-chain fatty acids. By comparing the economic and use values of these retrieved resources, it is concluded that a high-value resource transformation of municipal sludge can be achieved via the production of medium-chain fatty acids using anaerobic fermentation, which is a hotspot for future research. In this study, the selection of the pretreatment method, the method of producing medium-chain fatty acids, the influence of the electron donor, and the technique used to enhance product synthesis in the anaerobic fermentation process are introduced in detail. The study outlines potential future research directions for medium-chain fatty acid production using municipal sludge. These acids could serve as a starting point for investigating other uses for municipal sludge. [ABSTRACT FROM AUTHOR]

The limitation of enzymatic saccharification of lignocellulose is attributed to the nonproductive adsorption between lignin and cellulase. This study aims to investigate the effects of ozone pretreatment on the physical structure and chemical properties of milled wood lignin (MWL). The objective is to reduce the non-productive adsorption of cellulase on lignin. The structure–activity relationship between the physical structure of MWL and the occurrence of nonproductive adsorption was analysed using two-dimensional heteronuclear single quantum coherence–nuclear magnetic resonance (HSQC-NMR) and phosphorus-31 nuclear magnetic resonance spectrum (31P-NMR), etc. The results indicate that ozone pretreatment resulted in a decrease in the phenolic hydroxyl content and S/G ratio, an increase in the carboxyl content, and a negative zeta potential of MWL. The maximum adsorption capacity decreased from 25.77 mg/g to 10.09 mg/g, the Langmuir constant decreased from 13.86 mL/mg to 10.11 mL/mg, and the binding strength decreased from 357.14 mL/g to 102.04 mL/g, as determined by Langmuir isothermal adsorption. This suggests that ozone pretreatment resulted in a reduction in the hydrophobicity of lignin and a weakening of the electrostatic attraction between lignin and cellulase, thereby effectively reducing the non-productive adsorption of cellulase on lignin. This study provides an environmentally friendly pretreatment technique and comprehensively analyses the structural changes of ozone-treated MWL. These findings contribute to a deeper understanding of the interaction between lignin and cellulase. [ABSTRACT FROM AUTHOR]

The pollution from waste plastic express packages (WPEPs), especially microplastic (MP) fragments, caused by the blowout development of the express delivery industry has attracted widespread attention. On account of the variety of additives, strong complexity, and high diversity of plastic express packages (PEPs), the multi-class classification of WPEPs is a typical large-class-number classification (LCNC). The traceability and identification of microplastic fragments from WPEPs is very challenging. An effective chemometric method for large-class-number classification would be very beneficial for the comprehensive treatment of WPEP pollution through the recycling and reuse of waste plastic express packages, including microplastic fragments and plastic debris. Rather than using the traditional one-against-one (OAO) and one-against-all (OAA) dichotomies, an exhaustive and parallel half-against-half (EPHAH) decomposition, which overcomes the defects of the OAO's classifier learning limitations and the OAA's data proportion imbalance, is proposed for feature selection. EPHAH analysis, combined with partial least squares discriminant analysis (PLS-DA) for large-class-number classification, was performed on 750 microplastic fragments of polyethylene WPEPs from 10 major courier companies using near-infrared (NIR) spectroscopy. After the removal of abnormal samples through robust principal component analysis (RPCA), the root mean square error of cross-validation (RMSECV) value for the model was reduced to 0.01, which was 21.5% lower than that including the abnormal samples. The best models of PLS-DA were obtained using SNV combined with SG-17 smoothing and 2D (SNV+SG-17+2D); the latent variables (LVs), the error rates of Monte Carlo cross-validation (ERMCCVs), and the final classification accuracies were 6.35, 0.155, and 88.67% for OAO-PLSDA; 5.37, 0.103, and 87.33% for OAA-PLSDA; and 3.12, 0.054, and 96.00% for EPHAH-PLSDA. The results showed that the EPHAH strategy can completely learn the complex LCNC decision boundaries for 10 classes, effectively break the tie problem, and greatly improve the voting resolution, thereby demonstrating significant superiority to both the OAO and OAA strategies in terms of classification accuracy. Meanwhile, PLS-DA further maximized the covariance and data interpretation abilities between the potential variables and categories of microplastic debris, thereby establishing an ideal performance identification model with a recognition rate of 96.00%. [ABSTRACT FROM AUTHOR]

Each year, near 40 million tons of banana peels are discarded around the world. This plant biomass could potentially be utilized for energy production. Simultaneous saccharification and fermentation (SSF) is an effective method for producing biofuels from plant biomasses. Since SSF with enzymatic hydrolysis and fermentation are performed simultaneously in the same reactor, the production process is simpler than most existing methods. Here, we describe isobutanol production using SSF with hydrothermally treated banana peel samples and an Escherichia coli strain able to utilize glucose and xylose to produce isobutanol. To enhance the glucose and xylose concentrations, the reaction conditions for the enzymatic hydrolysis of plant biomass using two kinds of saccharification enzymes were optimized, including the enzyme unit ratio, reaction temperature and sample gram. When the optimized conditions for enzymatic hydrolysis were applied to SSF, the glucose and xylose produced from the hydrothermally treated samples were consumed, producing isobutanol. Moreover, the isobutanol concentration increased with an increasing initial culture pH, reaching 1.27 g/L at pH 6.5, which was consistent with the optimal initial culture pH for isobutanol production by this E. coli strain. Taken together, these results indicate that the established method is potentially useful for industrial isobutanol production. [ABSTRACT FROM AUTHOR]

Non-edible cellulosic biomass from perennial herbaceous plants is a promising and abundant feedstock for replacing slow-growing woody plants used in biotechnological applications. Herbaceous plant biomass, as other types of plant biomass, requires pretreatment before biochemical conversion. In this study, miscanthus straw was pretreated using different methods and subjected to enzymatic hydrolysis with Penicillium verruculosum enzyme complexes under laboratory conditions. The convertibility after enzymatic hydrolysis varied from 15% to 66%, depending on the pretreatment method. Dilute alkaline pretreatment showed the highest convertibility compared to other methods, reaching up to 66%. The efficiency of dilute acid pretreatment was relatively low compared to other methods. The maximum convertibility was 37% for sulfuric acid pretreatment (the least efficient) and 51% for nitric acid. Convertibility was almost equal with 43% for white liquor and 46% for hot water. The glucose-to-xylose ratio was 4.7:1 for dilute alkaline pretreatment and 11–13:1 for white liquor. Both sulfuric and nitric acid resulted in a low xylose content in the enzymatic hydrolysates. Low-xylose hydrolysates with less than 2% of the glucose amount can be produced by hot water pretreatment. Preparation C, enriched with endoglucanase I from T. reesei and endoglucanase II from P. verruculosum, was found to be the most effective of the different enzyme preparations (EPs) tested. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the effect of combined Free Nitrous Acid (FNA)-Heat (i.e., FNH) pretreatment on single- and two-stage anaerobic digestion (AD) of thickened waste-activated sludge (TWAS). Single-stage AD was conducted in batches, while two-stage AD involved acidogenic fermentation under semi-continuous flow followed by batch methanogenesis. FNH pretreatment was applied before the acidogenic stage, using 1.4 mg HNO2-N/L FNA concentration at 25 °C, 37 °C, and 60 °C for 24 h. Among the scenarios, the most promising results were observed with two-stage AD fed with FNH-pretreated TWAS at 60 °C, showing higher COD solubilization and a reduction in volatile solids. Combined FNA-Heat pretreatment in two-stage AD yielded elevated methane production (363–415 mL CH4/g VS added) compared to single-stage digestion. Methane yields from FNA-Heat pretreated single-stage ranged from 332 to 347 mL CH4/g VS added, contrasting with 212 mL CH4/g VS added for untreated TWAS. Methane generation commenced early in both untreated and pretreated samples, attributed to soluble substrate abundance. [ABSTRACT FROM AUTHOR]

The liquid biofuel bioethanol is widely produced worldwide via fermenting sugars extracted from a variety of raw materials, including lignocellulose biomass, one of the world's most abundant renewable resources. Due to its recalcitrant character, lignocellulose is usually pretreated by mechanical, chemical, and biological methods to maximize sugar recovery. Pretreated lignocellulose biomass undergoes a fermentation process performed sequentially or simultaneously to saccharification. The different fermentation strategies (e.g., separate or simultaneous hydrolysis and fermentation or co-fermentation) and conditions (e.g., inoculum type load, agitation, temperature, and pH) affect ethanol yield. Genetic modification of the inoculum has been focused recently to improve ethanol tolerance and as well as to use different sugars to enhance the performance of the microorganisms involved in fermentation. Nonetheless, these improvements result in a substantial increase in costs and have certain environmental costs. This review offers an overview of advancements in bioethanol production, with a primary focus on lignocellulosic feedstock, while also considering other feedstocks. Furthermore, it provides insights into the economic, social, and environmental impacts associated with bioethanol production. [ABSTRACT FROM AUTHOR]

Aerobic composting is one of the methods for the resource utilization of submerged plant residues. This study investigated the effects of biochar, wetland sediments and microbial agents added individually or combined on the humification process, lignocellulose degradation and microbial communities during Ceratophyllum demersum and Potamogeton wrightii composting. The results showed that the addition of wetland sediment and biochar was found to significantly elevate the composting temperature and humification of compost products. The average content of lignin in wetland sediment and/or biochar treatments was 12.2–13.5%, which was higher than the control group (10.9–11.45%). Compared with the organic matter (19.4%) and total nitrogen concentration (35.3%) of compost treated with complex microbial agent treatments, the homemade microbial agents significantly increased the values by 22.1% and 41.0%, respectively. By comparing the differences in microbial communities among different treatments, the sediments and homemade agents demonstrated greater increases in activity and diversity of lignocellulose degradation-related microbes, especially for Truepera and Actinomarinale. Humus component and temperature were the most critical parameters influencing the changes in the bacterial community. Based on these results, a combination of biochar and homemade agents was a promising additive for an effective composting strategy, and sediment was identified as a potential control of bacterial diversity in wetland plant compost. [ABSTRACT FROM AUTHOR]

Sugarcane bagasse (SCB) is an abundant agricultural waste, rich in cellulose and hemicellulose, that could be used as an ideal raw material for succinic acid (SA) production. A two-step chemical pretreatment, involving alkali extraction and alkaline hydrogen peroxide treatment, was utilized to treat SCB, followed by multi-enzyme hydrolysis to obtain a reducing sugar hydrolysate mainly composed of glucose and xylose. Optimization of the multi-enzyme hydrolysis of pretreated SCB resulted in a final reducing sugar concentration of 78.34 g/L. In order to enhance the bioconversion of SCB to SA and to reduce the production costs, the initial reducing sugar concentration, nitrogen source, and MgCO3 content were further optimized. The results demonstrated that the inexpensive corn steep liquor powder (CSLP) could be utilized as an alternative nitrogen source to yeast extract for the production of SA; and the optimal concentrations of initial reducing sugar, CSLP, and MgCO3 were 70 g/L, 18 g/L, and 60 g/L, respectively. When fed-batch fermentation was conducted in a 2 L stirred bioreactor, approximately 72.9 g/L of SA was produced, with a yield of 83.2% and a productivity of 1.40 g/L/h. The high SA concentration, yield, and productivity achieved in this study demonstrate the potential of SCB, an agricultural waste, as a viable alternative substrate for Actinobacillus succinogenes GXAS137 to produce SA. This lays a solid foundation for the resource utilization of agricultural waste and cost-effective industrial-scale production of SA in the future. [ABSTRACT FROM AUTHOR]

In the world, wastes/residues from agricultural activities are rapidly increasing, causing environmental problems. These wastes/residues can be used for the production of biohydrogen as a raw material. In this context, buckwheat crop residue, which has not been found in any study on biohydrogen production potential in the literature research, was investigated for biological hydrogen production via the dark fermentation method. This study was conducted in anaerobic batch bioreactors containing buckwheat or buckwheat extract + pretreated anaerobic mixed bacteria + nutrients, in a darkroom, at 37 ± 1 °C. Gas analyses, organic acid analyses and taxonomic content analyses were performed in bioreactors under different operating conditions (initial pH and organic loading rate). Biological hydrogen production was determined in all bioreactors. In addition, hydrogen production was found to be higher in bioreactors where biomass was used directly. The maximum biohydrogen production was determined to be 11,749.10−4 mL at 1.20 g. buckwheat/L and 446.10−4 mL at 1.20 g. buckwheat extract/L at pH 4.5. According to the taxonomic content species' level ratios, (i) in bioreactors where biomass was used directly, Hathewaya histolytica and Clostridium butyricum were detected at pH values of 4.5 and 4.0, respectively; and (ii) in bioreactors where biomass extract liquid was used, Clostridium butyricum and Clostridium tertium were determined as the most dominant bacteria at pH values of 4.5 and 4.0, respectively. [ABSTRACT FROM AUTHOR]

Lignocellulosic biomass represents the most abundant renewable carbon source on earth and is already used for energy and biofuel production. The pivotal step in the conversion process involving lignocellulosic biomass is pretreatment, which aims to disrupt the lignocellulose matrix. For effective pretreatment, a comprehensive understanding of the intricate structure of lignocellulose and its compositional properties during component disintegration and subsequent conversion is essential. The presence of lignin-carbohydrate complexes and covalent interactions between them within the lignocellulosic matrix confers a distinctively labile nature to hemicellulose. Meanwhile, the recalcitrant characteristics of lignin pose challenges in the fractionation process, particularly during delignification. Delignification is a critical step that directly impacts the purity of lignin and facilitates the breakdown of bonds involving lignin and lignin-carbohydrate complexes surrounding cellulose. This article discusses a two-step fractionation approach for efficient lignin extraction, providing viable paths for lignin-based valorization described in the literature. This approach allows for the creation of individual process streams for each component, tailored to extract their corresponding compounds. [ABSTRACT FROM AUTHOR]