Biomass Conversion and Biorefinery最新文献

Textile dye wastewater is a major global contributor to environmental pollution, characterized by complex physicochemical characteristics such as high stability, resistance to degradation, and potential toxicity. These effluents pose significant ecological risks, including aquatic toxicity, bioaccumulation, and the presence of carcinogenic and mutagenic compounds. This review critically synthesizes various treatment technologies, categorizing them into physicochemical, chemical, and biological methods, and highlights the limitations of conventional processes, such as high energy consumption and problematic sludge production. A core focus of this work is the comprehensive analysis of biological treatment approaches, particularly the enzyme-mediated degradation mechanisms involving oxidoreductases like azoreductases, laccases, and peroxidases. The review delves into the catalytic pathways of these enzymes and discusses the effectiveness of microbial systems (bacteria, fungi, yeast, and algae) in achieving high decolorization and mineralization efficiencies. By integrating recent data and comparative analyses of current research trends, this manuscript emphasizes the novelty of its mechanistic exploration and forward-looking perspective. It concludes by outlining critical research gaps and future directions, including the optimization of hybrid treatment systems, enzyme engineering, and the scaling of biotechnological processes for achieving sustainable, cost-effective, and complete textile dye wastewater remediation.

This critical review examines innovative bioprocessing techniques for agro-waste valorization, addressing the urgent environmental and economic challenges posed by agricultural waste. The paper evaluates microwave-assisted extraction, ultrasonic-assisted extraction, microbial and enzymatic bioconversion, solid-state fermentation, and anaerobic digestion for their potential to transform agro-waste into valuable resources. Recent data highlights significant agricultural production in countries like India, with sugarcane reaching 4905.3 lakh tonnes, generating substantial agricultural residues that are often disposed of through harmful practices like stubble burning. These practices release approximately 1,460 kg of CO₂ and 3 kg of particulate matter per tonne of paddy straw burned, exacerbating air pollution and climate change. The review demonstrates that microwave-assisted extraction reduces processing time from 8 h to just 1 h, while ultrasonic-assisted extraction achieves 72.5% protein recovery from canola meal. Solid-state fermentation increases protein content in agricultural byproducts by 34.91%, and anaerobic co-digestion boosts biogas output to 1732 ml compared to mono-digestion’s 1035 ml. The novelty of this work lies in its unique integration of non-conventional extraction techniques with smart technology solutions to maximize resource recovery and process efficiency. These approaches support sustainable waste management, reduce environmental pollution, and advance circular economy principles by repurposing waste into reusable resources. The study identifies major challenges including variability in waste characteristics, absence of standardized processing methods, and scalability constraints, recommending future research focus on standardized protocols, comprehensive characterization studies, and economic analyses to optimize conversion processes for global sustainability.

Fungi possess strong cellulolytic abilities, producing enzymes that can biodegrade complex compounds like cellulose, lignin, and hemicellulose. These abilities are valuable in industries, particularly those generating large amounts of waste, such as wastewater treatment plants, where hard-to-degrade compounds hinder efficient waste processing. Inoculation of the sewage sludge with autochthonous cellulolytic fungi may improve the hydrolysis and consequently methane yield, produced during anaerobic digestion. The usage of autochthonous fungi is dictated by its easier implementation not only at lab, but also at larger, industrial scale as a natural element of the substrate used. Moreover, such microorganisms usage will be not only beneficial for the process efficacy, but also safer for total community integrity regardless to scale. For the inoculation of sludge, twelve fungi strains with cellulolytic abilities were isolated, with seven capable of degrading cellulose under both aerobic and anaerobic conditions. Five strains, which showed the highest and similar to each other biodegradation effectivity in the pure cellulose degradation test were identified as Aspergillus terreus (3 strains) and Aspergillus fumigatus (2 strains). All isolated anaerobic fungi have been confirmed to produce Carboxymethyl Cellulase Assay for endo-β-1,4-glucanase (CMCase) and Filter Paper Assay for saccharifying cellulase (FPU Assay/FPase). The highest FPase (0.37 FPU/mL) was provided by G11 (A. fumigatus), and CMCase (1.49 U/mL) by G9 (A. terreus). The most stable degradation of the pure cellulose in anaerobic conditions and temperature of 37 °C in a 30-day test was provided by Aspergillus terreus (G3) (8.57%). Utilizing Aspergillus terreus in the Automatic Methane Potential Test System (AMPTS) resulted in an 11% increase in methane yield compared to untreated sludge, indicating enhanced degradation of organic matter during the anaerobic digestion. Methane yield in inoculated sludge was 164.2 N mL CH₄/g VS, whereas control samples showed 146.63 N mL CH₄/g VS. These findings highlight the potential of cellulolytic fungi to improve methane production from waste substrates.

The oxidative acid treatment on pristine biocarbon (derived from Gracilaria edulis seaweed biomass) was performed using concentrated hydrochloric acid (HCl), nitric acid (HNO₃), sulfuric acid (H₂SO₄), and hydrofluoric acid (HF) to investigate their impact on its physicochemical properties and capacitive performances. The physicochemical properties of acid treated biocarbons were identified by Fourier transform spectroscopy (FTIR), Raman spectroscopy, X-ray diffraction (XRD), Scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and Bet surface area (BET) analysis. Acid treatment removes the mineral impurities of biocarbons and creates pores, which enhancements their specific surface area. In addition, acid treatment also introduces new functional groups to biocarbons, which are the pathway for the electrolyte wettability and hence better ionic mobility. The biocarbon material treated with hydrofluoric acid (HF) showed larger specific surface area of 1250 m² g^− 1 and the highest specific capacitance of 158 F g^− 1 at 1 A g^− 1 using 1 M KOH as electrolyte. Additionally, it also exhibits a specific energy of 5.38 Wh kg^− 1 at a specific power of 495.39 W kg^− 1.

This study presents a novel approach to hyaluronic acid (HA) production from wild-type Bacillus subtilis strain PV154141.1, avoiding the need for genetic modifications commonly used in previous research. HA production was conducted under aseptic conditions using submerged fermentation in a medium containing glucose, lactose, yeast extract and tryptone. Critical fermentation parameters including media composition, incubation temperature, initial pH, and inoculum level, were optimized resulting in a significantly enhanced HA yield. Following optimization, HA was extracted using two distinct methods, the conventional ethanol method, which mainly relies on centrifugation and ethanol usage, and the CTAB-ethanol method, which involves greater volumes of cetyltrimethylammonium bromide (CTAB) and ethanol. Results indicated that the CTAB-ethanol method yielded significantly higher HA concentrations (472 µg/ml) compared to the conventional method (59.1 µg/ml), using the same experimental setup, because of the combined effect of CTAB, NaCl and ethanol for selective precipitation of HA, which is statistically significant (p ≤ 0.05). Fourier transform infrared (FTIR) spectroscopy further characterized the extracted HA, confirming its desired molecular structure and associated functional groups. Characteristic absorption peaks for HA were identified at 685.83, 834.92, 998.92, 1148.02, 1297.1, 1617.66, 2892.41, and 3257.69 cm^− 1. Each peak represents a specific biomolecule. The functional groups present in our sample included amide groups, hydroxyl groups, polyphenols, and proteoglycan sugar rings, confirming the presence of HA in the sample. The optimized fermentation process and a more efficient extraction technique contribute to advancing HA production methodologies. This research contributes a cost-effective and scalable approach to HA production, positioning wild-type B. subtilis as a promising non-GMO alternative for industrial applications in biotechnology, cosmetics and pharmaceuticals.

The global outbreak of virus has led to a dramatic increase in the generation of medical waste, posing severe challenges to conventional disposal methods such as incineration and landfilling, which are associated with high risks of secondary pollution and low resource recovery efficiency. This study systematically investigates the thermochemical conversion potential of discarded face masks (FM) and nitrile gloves (NG). Characteristic pyrolysis products of both materials within the temperature range of 450–650 °C were identified using pyrolysis–gas chromatography/mass spectrometry (Py-GC/MS): FM primarily produced 2,4-dimethyl-1-heptene, while NG was dominated by 1,3-butadiene. To elucidate the interaction mechanisms during co-pyrolysis, dynamic thermogravimetric analysis (TGA) combined with kinetic modeling was employed to explore the effects of blending ratios and heating rates (10–40 °C/min) on the pyrolysis process. Experimental results revealed that when NG accounted for 50–75% of the mixture, the system exhibited a dynamic phase transition at the critical temperature of 495 °C, where the synergistic effect shifted from negative to positive, indicating that the reaction pathway can be directionally regulated by adjusting the component ratio. More importantly, based on calculations using both the Kissinger-Akahira-Sunose (KAS) and Flynn-Wall-Ozawa (FWO) models, the average activation energy of the system at a FM/NG mass ratio of 1:1 significantly decreased to 265.78 kJ/mol. This finding demonstrates that co-pyrolysis effectively overcomes the energy barrier from both thermodynamic and kinetic perspectives.

This study investigates the catalytic performance of low loading Cu catalysts supported on rice husk-ash derived mesoporous silica support modified with metals (Al, Sn, Ti and Zr) for the vapor-phase hydrogenation of FFR to FAL. The catalysts underwent thorough characterization employing XRD, H₂-TPR, NH₃-TPD, FTIR, N₂ physisorption, XPS, and FESEM techniques, providing comprehensive insights into their properties. The analyses revealed significant structural modifications in the silica framework upon metal modification. XRD and N₂ physisorption analyses indicated the disruption of the mesoporous structure, accompanied by a reduction in surface area and pore volume. FTIR and XPS confirmed metal integration into the silica framework, improving the reducibility of the supported CuO species, as evidenced by H₂-TPR as well as improving the acidic site strength, as seen from NH₃-TPD. Further analysis through Auger spectroscopy revealed the dominance of Cu⁺ species in the catalysts with metal-incorporated silica support. The changes induced by metal modification became apparent during catalytic activity assessment where the incorporation of metals yielded increased FFR conversion and FAL yield over pure mesoporous supported catalyst. Zr-incorporated Catalyst (Cu@Zr-MS) yielded the most favourable outcomes among all catalysts, due to a combination of adequate acidic sites of appropriate strength, synergy between Cu⁰ and Cu⁺ species, the presence of oxygen vacancies and oxophilicity conferred by Zr. Optimization of process parameters revealed peak FFR conversion and FAL yield over Cu@Zr-MS at H₂/FFR = 10, Temperature = 200 °C, and WHSV = 1 g_FFR h^− 1 g_catalyst⁻¹, with respective values of 90.6% and 85% despite a small Cu loading. Assessment of catalytic performance over prolonged reaction duration demonstrated stable conversion at around 90%, alongside a sustained FAL yield of ~ 85% over approximately 16 h before a decline set in, with progressive deactivation that can be ascribed to sintering of Cu⁰ particles as well as the formation of amorphous carbonaceous species on the surface and/or inside catalyst’s pores.

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In many developing countries, repeated cropping removes soil nutrients and organic matter, leading to a gradual decline in soil fertility. This study converted the biodegradable fraction of MSW collected from the Mehmood Booti Dumping Site (Lahore, Pakistan) into biochar (pyrolysis at > 550 °C) and compost (pit composting, 60–70 days) and evaluated their individual and combined use as soil amendments for okra (Abelmoschus esculentus L.) in a pot experiment (RCBD, four replicates). Biochar production achieved a 33.3 ± 0.7% yield and was alkaline (pH 8.0 ± 0.2) with high ash content and cation exchange capacity, indicating strong potential for nutrient retention. Compost matured to a stable product with C/N 9.84 ± 0.1, confirming suitability as a nutrient-rich organic fertilizer. Compared with the unamended control, all amendments improved post-harvest soil properties, with the combined treatment (CB-5%) showing the strongest overall effect: CEC increased to 33.31 ± 1.11 cmolc kg⁻¹, bulk density decreased to 0.84 ± 0.11 g cm⁻³, water-holding capacity increased to 72.01 ± 1.10%, and soil organic matter rose to 5.84 ± 0.07%; macronutrients also peaked under CB-5% (N 1.85 ± 0.01%, P 1.93 ± 0.02%, K 2.23 ± 0.01%). These soil improvements translated into superior crop performance: CB-5% produced the greatest plant height (33.25 ± 0.25 cm), dry biomass (32.51 ± 0.57 g), chlorophyll content (68.33 ± 0.29 SPAD), and fruit yield (38.37 ± 0.29 g), outperforming chemical fertilizer (29.46 ± 0.44 g) and single-amendment treatments. These findings highlight the potential of MSW-derived biochar and compost as sustainable soil amendments, supporting integrated waste valorization and environmentally friendly agricultural practices.

This study examined biocrude production from Canadian spruce bark using hydrothermal liquefaction (HTL) to support integration of bio-crudes into existing refinery infrastructure. Across eight catalytic and non-catalytic HTL trials with spruce bark, biocrude yields ranged from 13.4 to 17.6 wt% (dry basis), showing that steam explosion and alkaline pretreatment did not improve yields. A central composite design (CCD) for non-catalytic HTL runs indicated that higher temperatures and water-to-feed ratios increase biocrude production, predicting a maximum of 20.8 wt% of biocrude yield at 320 °C and a water-to-feed ratio of 12.5:1 (wt./wt.). Validation runs under these conditions achieved a higher biocrude yield of 22.9 wt% with a higher heating value of 32.5 MJ kg⁻¹, 39.2% of energy recovery, and 19 wt% oxygen content - highlighting the need for upgrading the biocrude via catalytic deoxygenation. Recycling the aqueous phase increased yields by an additional 4 wt%. Hydrochar characterization also revealed promising potential applications such as hydrogen storage in fuel technologies, carbon sequestration, energy storage, catalyst support, and pollutant adsorption. Overall, spruce bark represents a viable feedstock for advancing production of sustainable fuels in Canada.

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The banana industry produces substantial biomass and waste, which can be transformed into high-value products through biorefineries. Components like banana peels and unsold ripe fruits are valuable raw materials for recovering functional ingredients. Banana peels, in particular, are rich in protein and fiber, with nutritional value varying by maturity and variety. Although research shows the potential of banana peels as a protein source and explores extraction methods, further studies are needed to understand their properties, applications, and fully understand their economic feasibility. This review categorizes banana biomass types, focusing on bioactive compounds in banana peels with pharmaceutical potential. It systematically evaluates protein isolation methods based on efficiency, scalability, and purity, and assesses the pharmacological properties of bioactive proteins, including their antimicrobial, antioxidant, and antihypertensive effects. The review also offers evidence-based recommendations for developing pharmaceutical products from these compounds, addressing challenges and future research directions.